STAAD.Pro V8i (SELECTseries 3) International Design Codes Manual DAA037810-1/0004 Last updated: 10 October 2011 Copyright Information Trademark Notice Bentley, the "B" Bentley logo, STAAD.Pro are registered or nonregistered trademarks of Bentley Sytems, Incorporated or Bentley Software, Inc. All other marks are the property of their respective owners. Copyright Notice © 2011, Bentley Systems, Incorporated. All Rights Reserved. Including software, file formats, and audiovisual displays; may only be used pursuant to applicable software license agreement; contains confidential and proprietary information of Bentley Systems, Incorporated and/or third parties which is protected by copyright and trade secret law and may not be provided or otherwise made available without proper authorization. Acknowledgments Windows, Vista, SQL Server, MSDE, .NET, DirectX are registered trademarks of Microsoft Corporation. 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Unpublished - rights reserved under the Copyright Laws of the United States and International treaties. End User License Agreements To view the End User License Agreement for this product, review: eula_en.pdf. International Design Codes Manual — i Table of Contents About STAAD.Pro About the STAAD.Pro Documentation Getting Started and Tutorials Examples Manual Graphical Environment Technical Reference Manual International Design Codes 2 4 4 4 4 5 5 Batch Design versus Design Modes Batch Design Design Modes 6 6 6 Section 1 Australian Codes 1A. Australian Codes - Concrete Design per AS 3600 - 2001 1B. Australian Codes - Steel Design per AS 4100 - 1998 9 11 19 Section 2 British Codes 2A. British Codes - Concrete Design per BS8110 2B. British Codes - Steel Design per BS5950:2000 2C. British Codes - Design per BS5400 2D. British Codes - Design per BS8007 2E. British Codes - Design per British Cold Formed Steel Code 49 51 67 93 97 101 Section 3 Canadian Codes 3A. Canadian Codes - Concrete Design per CSA Standard A23.3-94 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 3C. Canadian Codes - Design Per Canadian Cold Formed Steel Code S136-94 3D. Canadian Codes - Wood Design Per CSA Standard CAN/CSA-086-01 119 121 129 165 173 Section 4 Cypriot Codes 4A. Cypriot Codes - Concrete Design in Cyprus 193 195 International Design Codes Manual — iii Section 5 Danish Codes 5A. Danish Codes - Steel Design per DS412 201 203 Section 6 Dutch Codes 6A. Dutch Codes - Steel Design per NEN 6770 207 209 Section 7 European Codes 7A. European Codes - Concrete Design Per Eurocode EC2 7B. European Codes - Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] 7D. European Codes - National Annexes to Eurocode 3 [EN 1993-1-1:2005] 7E. Timber Design Per EC 5: Part 1-1 213 215 221 237 283 349 Section 8 Finnish Codes 8A. Finnish Codes - Concrete Design per B4 8A. Finnish Codes - Steel Design per B7 369 371 375 Section 9 French Codes 9A. French Codes - Concrete Design per B.A.E.L 9B. French Codes - Steel Design per the French Code 379 381 387 Section 10 German Codes 10A. German Codes - Concrete Design Per DIN 1045 10B. German Codes - Steel Design Per the DIN Code 397 399 407 Section 11 Indian Codes 11A. Indian Codes - Concrete Design per IS 456 11B. Indian Codes - Concrete Design per IS 13920 11C. Indian Codes - Steel Design per IS 800 - 1984 11D. Indian Codes - Steel Design per IS 802 11E. Indian Codes - Design per Indian Cold Formed Steel Code 11F. Indian Codes - Steel Design per IS 800:2007 417 419 441 465 483 505 513 Section 12 Japanese Codes 12A. Japanese Codes - Concrete Design Per 1991 AIJ 541 543 iv — STAAD.Pro 12B. Japanese Codes - Steel Design Per 2005 AIJ 12C. Japanese Codes - Steel Design Per 2002 AIJ 551 565 Section 13 Mexican Codes 13A. Mexican Codes - Concrete Design Per MEX NTC 1987 13B. Mexican Codes - Steel Design Per NTC 1987 583 585 597 Section 14 Norwegian Codes 14A. Norwegian Codes - Steel Design per NS 3472 / NPD 14B. Norwegian Codes - Steel Design per NORSOK N-004 14C. Norwegian Codes - Concrete Design per NS 3473 607 609 663 685 Section 15 Russian Codes 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* 15B. Russian Codes - Steel Design Per SNiP 2.23-81* (Edition 1999) 689 691 719 Section 16 Singaporian Codes 16A. Singaporean Codes - Concrete Design per CP65 737 739 Section 17 South African Codes 17A. South African Codes - Concrete Design per SABS-0100-1 17B. South African Codes - Steel Design Per SAB Standard SAB0162-1:1993 745 747 753 Section 18 Spanish Codes 18A. Spanish Codes - Steel Design per NBE-MV103-1972 18A. Spanish Codes - Concrete Design per EHE 773 775 777 Section 19 Swedish Codes 19A. Swedish Codes - Steel Design per BSK 99 19B. Swedish Codes - Concrete Design per BBK 94 781 783 787 Section 20 American Aluminum Code Section 21 American Transmission Tower Code 21A. American Transmission Tower Code - Steel Design per ASCE 10-97 793 805 807 21B. American Transmission Tower Code - Steel Design per ASCE Manuals and Reports 813 International Design Codes Manual — v Section 22 Steel Design per American Petroleum Institute Code Section 23 ANSI/AISC N690 Design Codes 23A. ANSI/AISC N690-1994 Code 23B. ANSI/AISC N690-1984 Code 819 835 837 853 Section 24 American Society of Mechanical Engineers – Nuclear Facility (ASME NF) Codes 873 24A. ASME NF 3000 - 1974 & 1977 Codes 24B. ASME NF 3000 - 1989 Code 24B. 18B.6 Example 24C. ASME NF 3000 - 2004 Code 24C. 18C.6 Example 24D. ASME NF 3000 - 2004 Code 875 885 892 897 905 909 Section 24 Technical Support 921 vi — STAAD.Pro This documentation has been prepared to provide information pertaining to the various international codes supported by STAAD. These codes are provided as additional codes by Bentley Sytems, Incorporated. In other words, they do not come with the standard license package. Hence, information on only some of the codes presented in this document may be actually pertinent to the license package available to you. This document is to be used in conjunction with the STAAD Technical Reference Manual and the STAAD Application Examples Manual . Effort has been made to provide some basic information about the analysis considerations and the logic used in the design approach. A brief outline of the factors affecting the design along with references to the corresponding clauses in the codes is also provided. Examples are provided at the appropriate places to facilitate ease of understanding of the usage of the commands and design parameters. You are urged to refer to the Examples Manual for solved problems that use the commands and features of STAAD. Since the STAAD output contains references to the clauses in the code that govern the design, we recommend that you consult the documentation of the code of that country for additional details on the design criteria. International Design Codes Manual — 1 About STAAD.Pro About STAAD.Pro STAAD.Pro is a general purpose structural analysis and design program with applications primarily in the building industry - commercial buildings, bridges and highway structures, industrial structures, chemical plant structures, dams, retaining walls, turbine foundations, culverts and other embedded structures, etc. The program hence consists of the following facilities to enable this task. 1. Graphical model generation utilities as well as text editor based commands for creating the mathematical model. Beam and column members are represented using lines. Walls, slabs and panel type entities are represented using triangular and quadrilateral finite elements. Solid blocks are represented using brick elements. These utilities allow the user to create the geometry, assign properties, orient cross sections as desired, assign materials like steel, concrete, timber, aluminum, specify supports, apply loads explicitly as well as have the program generate loads, design parameters etc. 2. Analysis engines for performing linear elastic and pdelta analysis, finite element analysis, frequency extraction, and dynamic response (spectrum, time history, steady state, etc.). 3. Design engines for code checking and optimization of steel, aluminum and timber members. Reinforcement calculations for concrete beams, columns, slabs and shear walls. Design of shear and moment connections for steel members. 4. Result viewing, result verification and report generation tools for examining displacement diagrams, bending moment and shear force diagrams, beam, plate and solid stress contours, etc. 5. Peripheral tools for activities like import and export of data from and to other widely accepted formats, links with other popular softwares for niche areas like reinforced and prestressed concrete slab design, footing design, steel connection design, etc. 6. A library of exposed functions called OpenSTAAD which allows users to access 2 — STAAD.Pro About STAAD.Pro STAAD.Pro’s internal functions and routines as well as its graphical commands to tap into STAAD’s database and link input and output data to third-party software written using languages like C, C++, VB, VBA, FORTRAN, Java, Delphi, etc. Thus, OpenSTAAD allows users to link in-house or third-party applications with STAAD.Pro. International Design Codes Manual — 3 About the STAAD.Pro Documentation Getting Started and Tutorials About the STAAD.Pro Documentation The documentation for STAAD.Pro consists of a set of manuals as described below. These manuals are normally provided only in the electronic format. All the manuals can be accessed from the Help facilities of STAAD.Pro. If you want to obtain a printed copy of the books, visit the docs.bentley.com site to check availability and order. Bentley also supplies the manuals in the PDF format at no cost for those who want to print them on their own. See the back cover of this book for addresses and phone numbers. Getting Started and Tutorials This manual contains information on the contents of the STAAD.Pro package, computer system requirements, installation process, copy protection issues and a description on how to run the programs in the package. Tutorials that provide detailed and step-by-step explanation on using the programs are also provided. Examples Manual This book offers examples of various problems that can be solved using the STAAD engine. The examples represent various structural analyses and design problems commonly encountered by structural engineers. Graphical Environment This document contains a detailed description of the Graphical User Interface (GUI) of STAAD.Pro. The topics covered include model generation, structural analysis and design, result verification, and report generation. 4 — STAAD.Pro About the STAAD.Pro Documentation Technical Reference Manual This manual deals with the theory behind the engineering calculations made by the STAAD engine. It also includes an explanation of the commands available in the STAAD command file. International Design Codes This document contains information on the concrete, steel, aluminum, and timber design codes that are supported in the batch design routines. Note that most steel and concrete batch design routines for the US design codes can be found in the Technical Reference Manual. Details of the steel design codes supported in the post processing Steel Design Mode can be found in the User Interface manual. Details of the beam, column and slab concrete design codes supported in the Concrete Design Mode can be found in the RC Designer manual. The documentation for the STAAD.Pro Extension component(s) is available separately. International Design Codes Manual — 5 Batch Design versus Design Modes Batch Design Batch Design versus Design Modes STAAD.Pro has two means by which structural members can be designed. Batch Design Using this method, code checks and/or member selection is performed directly by the analysis and design engine when an analysis is performed. The contents of this manual, along with those in the Technical Reference manual, are all used for batch design. Design Modes Code checks and member selection is performed in a post-processing module for either Steel Design or Concrete Design. These modes are available in the Graphical User Interface. Refer to the Steel Design mode and Concrete Design mode help sections for additional information. Table 14.1-Available steel design codes in the Steel Design mode Country/Region Egypt Europe Great Britain India United States Code 205 2001 EC3 DD BS5950 2000 IS 800 AISC ASD 6 — STAAD.Pro Batch Design versus Design Modes Note: Design per the Chinese steel code GB50017-2003 must be performed per the localized STAAD SSDD interface. Please download and install this application from Bentley SELECT. Table 14.2-Available design codes in the Concrete Design codes Country/ Region Australia China Egypt Europe Eurocode 2 - 2004 France Germany Great Britain India Japan Norway Russia Singapore Spain Turkey BAEL DIN 1045-1 BS 8110 IS456 AIJ NS3473 SP52-101-03 CP65 EHE TS 500 ACI 318-99 United States ACI 318-05 / 318M-05 Code AS 3600 GB50010 ECCS 203 Eurocode 2 - 1991 International Design Codes Manual — 7 8 — STAAD.Pro Section 1 Australian Codes International Design Codes Manual — 9 10 — STAAD.Pro 1A. Note: Once a parameter is specified. the first set of members are rectangular (450 mm depth and 250mm width) and the second set of members. Table 1A. with only depth and no width provided. its value stays at that specified number until it is specified again.Concrete Design per AS 3600 .2001 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack.1A. International Design Codes Manual — 11 .3 Design Parameters The program contains a number of parameters which are needed to perform the design. This is the way STAAD works for all codes. 11 13 PR YD 350. will be assumed to be circular with 350 mm diameter. The following example shows the required input: UNIT MM MEMBER PROPERTY 1 3 TO 7 9 PRISM YD 450. 1A. ZD 250. and Circular) 1A. It is absolutely imperative that the user not provide the cross section area (AX) as an input. Design of members per AS 3600 .Pro is capable of performing concrete design based on the Australian code AS 36002001 Australian Standard-Concrete Structures. l l For Beams: Prismatic (Rectangular & Square) For Columns: Prismatic (Rectangular.2 Member Dimensions Concrete members which will be designed by the program must have certain section properties input under the MEMBER PROPERTY command. Square. Australian Codes .2001 STAAD. These values may be changed to suit the particular design being performed. It is necessary to declare length and force units as Millimeter and Newton before performing the concrete design. In the above input.1 Section Types for Concrete Design The following types of cross sections for concrete members can be designed.1 of this manual contains a complete list of the available parameters and their default values. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements. Concrete Design per AS 3600 . Australian Codes . Concrete Yield Stress.1. Applicable values per Clause 6. This value defaults to YD as provided under MEMBER PROPERTIES.2.Pro . For column members Total depth to be used for design.2 of the Technical Reference Manual.2001.52.2001 Table 1A.1 of AS 36002001: 20 25 32 40 50 65 FYMAIN 450 N/mm 2 Yield Stress for main reinforcing steel.1-Australian Concrete Design per AS 3600 Parameters Parameter Name CODE Default Value Description Must be specified as AUSTRALIAN to invokes design per AS 3600 .1A. CLEAR 25 mm 40 mm DEPTH YD For beam members. Design Code to follow. Applicable values per Table 6.1. See section 5.1 of AS 36002001: 250 400 450 500 FMC 40 N/mm 2 12 — STAAD. Maximum secondary reinforcement bar size.2. Applicable values per Table 6.0 REINF 0. Minimum secondary reinforcement bar size. MINMAIN 10 mm MAXSEC 12 mm MINSEC 8 mm RATIO 4. A value of 1.0 International Design Codes Manual — 13 .1 of AS 36002001: 250 400 450 500 MAXMAIN 60 mm Maximum main reinforcement bar size. Minimum main reinforcement bar size. Maximum percentage of longitudinal reinforcement in columns.Parameter Name FYSEC Default Value 450 N/mm 2 Description Yield Stress for secondary reinforcing steel. Tied column.0 will mean spiral reinforcement. 0 = required steel for intermediate sections defined by NSECTION are printedin addition to TRACK 0. additional moments are calculated based on empirical formula and assumptions on sidesway.0 Description For beam design: 0. and end 1. a P-Delta analysis—as performed by STAAD—may be used for the design of concrete members. 1A.0 output For column design: 0. One option is to perform an exact analysis which will take into account the influence of axial loads and variable moment of inertia on member stiffness and fixed end moments.0 = output consists of reinforcement details at the member start. except for the effects of the duration of the loads. use the command PDELTA ANALYSIS instead of PERFORM ANALYSIS. There are two options by which the slenderness effect can be accommodated.2001 Parameter Name TRACK Default Value 0.0 = reinforcement details are printed WIDTH ZD Width to be used for design.Concrete Design per AS 3600 .Pro . middle. To perform this type of analysis. This value defaults to ZD as provided under MEMBER PROPERTIES. it must be realized that the evaluation of slenderness effects is also by an approximate method. Considering all of the above information. the effect of deflections on moment and forces and the effect of the duration of loads. In this method.0 output 2. It is felt that this effect may be safely ignored because experts believe that the effects of the duration of loads are negligible in a normal structural configuration. Another option is to approximately magnify design moments. Australian Codes . STAAD has been written to allow the use of the first option.order analysis described by AS 3600. Although ignoring load duration effects is somewhat of an approximation.0 = critical moments are printed in addition to TRACK 0.4 Slenderness Effects and Analysis Consideration Slenderness effects are extremely important in designing compression members. However the user must note that to take 14 — STAAD.1A. The PDELTA ANALYSIS will accommodate the requirements of the second. 1. whereas a primary load case is revised during the P-delta analysis based on the deflections.5 for dead load etc. In the first pass.7. All of these sections are scanned to determine the design force envelopes.25. Efforts have been made to meet the guideline for the curtailment of reinforcements as per AS 3600. 1A. effective depths of the sections are determined with the assumption of single layer of assumed reinforcement and reinforcement requirements are calculated.) should be provided by the user. STAAD does not factor the loads automatically. . . This is due to the fact that load combinations are just algebraic combinations of forces and moments.g. .2 Design for Shear Shear reinforcement is calculated to resist both shear forces and torsional moments.. Currently. If the section dimensions are inadequate as a singly reinforced section. Final provisions of flexural reinforcements are made then. Two-legged stirrups are provided to take care of the balance shear forces acting on these sections.9. 0.6. 1A. . The total number of sections considered is 13 (e. user has the choice of printing reinforcements provided by STAAD at 13 equally spaced sections from which the final detailed drawing can be prepared. Shear design is performed at 13 equally spaced sections (0. all the combinations of loading must be provided as primary load cases and not as load combinations. . Shear capacity calculation at different sections without the shear reinforcement is based on the actual tensile reinforcement provided by STAAD.3. Each of these sections is designed to resist both of these critical sagging and hogging moments.8. . .5. 1A..) for the maximum shear forces amongst the active load cases and the associated torsional moments. For all these forces. .75. shear and torsion. . . Also.1 Design for Flexure Maximum sagging (creating tensile stress at the bottom face of the beam) and hogging (creating tensile stress at the top face) moments are calculated for all active load cases at each of the above mentioned sections. design of singly reinforced sections only is permitted. note that the proper factored loads (like 1. to 1. Although exact curtailment lengths are not mentioned explicitly in the design output (finally which will be more or less guided by the detailer taking into account of other practical consideration). reinforcing bars are chosen from the internal database in single or multiple layers. and 1). all active beam loadings are prescanned to identify the critical load cases at different sections of the beams.5.4.advantage of this analysis.2.5. Example of Input Data for Beam Design: UNIT NEWTON MMS START CONCRETE DESIGN International Design Codes Manual — 15 . such a message will be permitted in the output. After the preliminary design. The entire flexure design is performed again in a second pass taking into account the changed effective depths of sections calculated on the basis of reinforcement provided after the preliminary design. Flexural design of beams is performed in two passes.5 Beam Design Beams are designed for flexure. . That means the total number of bars will always be a multiple of four (4).1A. it must be modeled using finite elements. MAXMAIN.2001 CODE AUSTRALIAN FYMAIN 415 ALL FYSEC 415 ALL FC 35 ALL CLEAR 25 MEM 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 TRACK 1.0 MEMB 2 TO 9 DESIGN BEAM 2 TO 9 END CONCRETE DESIGN 1A. rectangular and circular sections. Column design is done for square. FC. The parameters FYMAIN. The command specifications are in accordance with Chapter 2 and Chapter 6 of the specification.8 of the Technical Reference Manual).Pro . and CLEAR listed in Table 1A. Other parameters mentioned in Table 1A.Concrete Design per AS 3600 .7 Slab or Wall Design To design a slab or wall. All major criteria for selecting longitudinal and transverse reinforcement as stipulated by AS 3600 have been taken care of in the column design of STAAD. square and rectangular columns are designed with reinforcement distributed on each side equally. These moments are obtained from the element force output (see Section 3. Example of Input Data for Column Design: UNIT NEWTON MMS START CONCRETE DESIGN CODE AUSTRALIAN FYMAIN 415 ALL FC 35 ALL CLEAR 25 MEMB 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 DESIGN COLUMN 2 TO 6 END CONCRETE DESIGN 1A. The reinforcement required to resist Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist My moment is denoted as transverse reinforcement. Elements are designed for the moments Mx and My. Australian Codes .1 are relevant to slab design. This may cause slightly conservative results in some cases.1 are not applicable to slab design. 16 — STAAD. MINMAIN. All active load cases are tested to calculate reinforcement.6 Column Design Columns are designed for axial forces and biaxial moments at the ends. By default. The loading which yields maximum reinforcement is called the critical load. 1 .Figure 1A.Element moments: Longitudinal (L) and Transverse (T) Example of Input Data for Slab/Wall Design UNIT NEWTON MMS START CONCRETE DESIGN CODE AUSTRALIAN FYMAIN 415 ALL FC 25 ALL CLEAR 40 ALL DESIGN ELEMENT 15 TO 20 END CONCRETE DESIGN International Design Codes Manual — 17 . 18 — STAAD.Pro . Details are provided in the sections that follow. A detailed description of the design process along with its underlying concepts and assumptions is available in the specification document.4. the most economic section is selected on the basis of the least weight criteria as augmented by the designer in specification of allowable member depths. members are proportioned to resist the design loads without exceeding the limit states of strength.1 Strength Limit States Strength design capacities (φRu) are calculated and compared to user-defined design action effects (S*). stability. and DJ2 design parameters. however this is only available for MEMBER Design.2 Deflection Limit States STAAD.Steel Design per AS 4100 .1998 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack.1. In the STAAD implementation. Appropriate load and resistance factors are used so that a uniform reliability is achieved for all steel structures under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. The primary considerations in ultimate limit state design are strength and stability. desired section type.1998 STAAD. Two major categories of limit-state are recognized . Note: Local member deflections parallel to the local member y-axis can be checked against a user-defined maximum “span / deflection” ratio. The following sections describe the salient features of the STAAD implementation of AS 4100. Details for design capacity calculations are outlined in the sections that follow. or other such parameters. Design of members per AS 3600 . It is left to the user to check that both local member and frame deflections are within acceptable limits. so as to ensure that S* ≤ φRu in accordance with AS 4100 3. The code checking portion of the program checks whether code requirements for each selected section are met and identifies the governing criteria.1 General The design philosophy embodied in this specification is based on the concept of limit state design.Pro’s AS 4100 implementation does not generally check deflections. Australian Codes . DJ1. International Design Codes Manual — 19 . 1B. and serviceability. 1B. This can be performed using the DFF. Accordingly.Steel Structural Design. while that in serviceability is deflection.1.ultimate and serviceability. 1B.1B. Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use.Pro is capable of performing steel design based on the Australian code AS 4100-1998 Standards Australia . 7 AS 4100 3.25 of the Technical Reference manual for further information on the Member Offset feature.1998 1B. Refer to Section 5.Pro’s implementation of AS 4100.1.Pro and Bentley’s RAM Connection program currently do not support design of connections in accordance with AS 4100.11 Stability Serviceability Brittle Fracture Fire Other Design Requirements 1B.Pro AS 4100 Design Limit State Code Reference AS 4100 3.5 AS 4100 3.1-Limit States Not Considered in STAAD.9 AS 4100 3. 1B. Such considerations are not considered in STAAD. 1B.Pro .Pro’s AS 4100 and should be checked by separately.3 Eccentric Beam Reactions STAAD.3.4. However member offsets can be used to model these eccentricities.1. Table 1B.4 Limit States Not Considered The following limit states are not directly considered in STAAD. Note: NSC and NSF design parameters are used to manually specify a reduction in net section area for compression or tension capacity calculations.1B. 20 — STAAD.1.Steel Design per AS 4100 . In some cases connection design may govern the size of members.5 Connection Design STAAD. Further details are provided in the sections that follow.Pro does not automatically account for minimum eccentricity distances for beam reactions being transferred to columns as per AS 4100 4.6 Bolts and Welds Bolt holes and welds are not generally considered in STAAD.3 AS 4100 3. These can be used to account for bolt hole area reductions.Pro’s AS 4100 member design.1. Australian Codes . 4.1. Dynamic analysis may also be performed and the results combined with static analysis results. Refer Section 5. 1B.32.2.37. Therefore.10 of the Technical Reference Manual for further information on Dynamic Loading and Analysis features. You are allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations. Elastic Analysis .Pro.37. Load Combinations are combinations of results where Repeat Loads instruct the program to perform the analysis on the combined load actions. it is your responsibility to enter all necessary loads and load combination factors for design in accordance with the AS/NZS 1170 Series or other relevant design codes. Note: Moment amplification as per AS 4100 clause 4. ii.4.used to perform a regular elastic stiffness analysis as per AS 4100 4. Note: Plastic analysis and design in accordance with AS 4100 section 4.11 of the Technical Reference Manual for additional details on using Repeat Loads. Analysis is done for the specified primary and repeat loading conditions. Refer to Section 5. Refer to Section 5. a PDelta analysis may be required in order to capture second-order effects as per AS 4100 4.2 of the Technical Reference Manual for additional details on this feature.1.Pro in accordance with AS 4100: i.2. Elastic Analysis .Pro by performing a PDelta second-order elastic analysis as per AS 4100 Appendix E.1 Elastic Analysis Two types of elastic analysis can be performed using STAAD. Hint: In order to correctly capture second-order effects for combination load cases using a PDelta Analysis. Second Order PDelta Linear.2 Dynamic Analysis Dynamic analysis may also be performed and the results combined with static analysis results.1 of the Technical Reference Manual for additional details on this feature.2 Analysis Methodology Either the elastic or dynamic analysis methods may be used to obtain the forces and moments for design as per AS 4100 section 4.4. Depending upon the analysis requirements. International Design Codes Manual — 21 .4.2. regular stiffness analysis or P-Delta analysis may be specified. Refer to Section 5.32. First Order Linear. 1B.2 is not considered. Second-order effects will not be correctly evaluated if the Load Combination feature is used. the Repeat Load feature must be used.Depending on the type of structure.2. Second-order effects can be captured in STAAD.1B.5 is not implemented in STAAD. 2 of the Technical Reference Manual for additional information. and Top & Bottom Cover Plates (TB). An example of the member property specification in an input file is provided at the end of this section. Bottom Cover Plates (BC). RHS CHS Description Welded beams and columns Universal beams and columns Tees cut from universal beams and columns Parallel flange channels Equal and unequal angles Square and rectangular hollow sections Circular hollow sections Note: STAAD. UC T-SECTION CHANNEL ANGLE TUBE PIPE BT. the properties are also used for member design. Refer to Section Profile Tables in the Graphical Environment for these options.Pro AS 4100 Design General Profile Type Australian Sections I-SECTION WB. refer to Section 1. 1B. BA. select File > Configuration from the 22 — STAAD. shear deformation is always considered during the analysis of these members. STAAD.Steel Design per AS 4100 . Table 1B. The next section describes the syntax of commands used to assign properties from the built-in steel table.3 Member Property Specifications For specification of member properties. CT PFC EA.Pro’s default tables are American. To change the default tables to Australian.Pro .7. & FR) and Double Angles (LD & SD).7 the STAAD Technical Reference Manual. Australian Codes . These properties are stored in a database file.2-Available Australian Sections for STAAD.1B. Double Channels (D. Composite Sections (C). Since the shear areas are built into these tables.4 Built-in Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. For more information on these facilities. Hint: When adding and assigning sections using the built-in steel section library through the Graphical Environment. either the steel section library available in STAAD or the User Table facility may be used. Refer to Section 1. A complete listing of the sections available in the built-in steel section library may be obtained by using the tools of the graphical user interface. If called for. UA SHS. WC UB.Pro will not design the following section types to AS 4100: Double Profiles (D). Top Cover Plates (TC).1998 1B. 4.3 Welded Beams Welded Beams are designated in the following way.0 36 TO 46 TA ST UB180X16.4.1 1B.5 Parallel Flange Channels Shown below is the syntax for assigning names of channel sections.1 UB Shapes These shapes are designated in the following way.4.Pro Start page (no input file open). 25 TO 35 TA ST WC400X114 23 56 TA ST WC400X303 1B. Following are the descriptions of different types of sections.4.4 Welded Columns Welded Columns are designated in the following way.8 23 56 TA ST UC310X96.4. 20 TO 30 TA ST UB150X14. 1 TO 5 TA ST PFC75 6 TO 10 TA ST PFC380 International Design Codes Manual — 23 . 1B. 25 TO 35 TA ST WB700X115 23 56 TA ST WB1200X455 1B.STAAD.8 1B. Set the Default Profile Table to Australian on the Configure Program dialog Section Profile Table.2 UC Shapes The designation for the UC shapes is similar to that for the UB shapes. 25 TO 35 TA ST UC100X14. 7 Angles Two types of specification may be used to describe an angle.5 length units between the channels. 17 21 TA RA A150X150X16 Note: Single angles must be specified with an “RA” (Single Angle w/Reverse Y-Z Axis) in order to be designed to AS 4100.1B. Member 17 is a double channel PFC300 with a spacing of 0.8 Double Angles Short leg back-to-back or long leg back-to-back double angles can be specified by means of input of the words SD or LD.1998 1B.75 24 — STAAD. are available. The standard angle section is specified as follows: 16 20 TA ST A30X30X6 The above section signifies an angle with legs of length 30 mm and a leg thickness of 6 mm. 1B. type specification "RA" (reverse angle) may be used.6 Double Channels Back-to-back double channels.4. respectively. In case of an equal angle. The letter D in front of the section name will specify a double channel. If the local Y axis corresponds to the z-z axis.6 37 39 TA LD A75X50X6 43 TO 47 TA LD A100X75X10 SP 0. member 11 is a back-to-back double channel PFC230 with no spacing in between. in front of the angle size. 33 35 TA SD A65X50X5 SP 0. Australian Codes . with or without a spacing between them. This is to ensure that the major and minor principal axes align with the local member z and y axes respectively. similar to other section profiles.4.Steel Design per AS 4100 .Pro .4. either SD or LD will serve the purpose. 1B. This specification may be used when the local Z axis corresponds to the z-z axis specified in Chapter 2.5 In the above set of commands. 11 TA D PFC230 17 TA D C230X75X25 SP 0. 5 In the second method. The name is obtained as 10 times the depth.0 specifies a pipe with outside diameter of 25 length units and inside diameter of 20 length units. 1 TO 5 TA ST PIP180X5 6 TO 10 TA ST PIP273X6. and members 6 to 10 consist of 10X5X0.1875 inch size tube section. 1B.5 is a tube that has a height of 8 length units. This method is meant for pipes whose property name is available in the steel table.4. In the first method. 10 times the width.11 Sample File Containing Australian Shapes STAAD SPACE UNIT METER KN JOINT COORD 1 0 0 0 11 100 0 0 MEMB INCI 1 1 2 10 International Design Codes Manual — 25 .4. will be performed on pipes specified in this latter manner.10 Pipes (Circular Hollow Sections) Pipes can be assigned in 2 ways. In these examples.5 inch size tube section. Only code checking. the designation for the tube is as shown below.1B.9 Tubes (Rectangular or Square Hollow Sections) Tubes can be assigned in 2 ways. tubes are specified by their dimensions.0 In the second method. 1 TO 9 TA ST PIPE OD 25.0 WT 6. For example. width of 6 length units. and a wall thickness of 0.0 TH 0. 1 TO 5 TA ST TUB20202. 1B. pipe sections may be provided by specifying the word PIPE followed by the outside and inside diameters of the section. 6 TA ST TUBE DT 8. In the first method.4. Only code checking. This method is meant for tubes whose property name is available in the steel table. no member selection. the designation for the pipe is as shown below.0 ID 20. and 16 times the thickness. will be performed for TUBE sections specified in this latter manner. For example.5 length units.5 6 TO 10 TA ST TUB100503. members 1 to 5 consist of a 2X2X0. no member selection. Steel Design per AS 4100 .6 * DOUBLE ANGLES . Australian Codes . 1B. The design procedures are different depending on the section class.1998 UNIT CM MEMBER PROPERTIES AUSTRALIAN * UB SHAPES 1 TA ST UB200X25. the user can use either: a. Steel sections are classified as compact. local buckling becomes an important criterion. STAAD determines the section classification for the standard shapes and user specified shapes. built-in material constants b.Pro . This classification is a function of the geometric properties of the section. or slender.75 * TUBES (RECTANGULAR OR SQUARE HOLLOW SECTIONS) 9 TA ST TUBE DT 8.0 ID 20. noncompact.5 Section Classification The AS 4100 specification allows inelastic deformation of section elements. Thus. depending upon their local buckling characteristics.5 * CHANNELS 3 TA ST PFC125 * DOUBLE CHANNELS 4 TA D PFC200 * ANGLES 5 TA ST A30X30X6 * REVERSE ANGLES 6 TA RA A150X150X16 * DOUBLE ANGLES .4 * UC SHAPES 2 TA ST UC250X89.1B.SHORT LEGS BACK TO BACK 7 TA SD A65X50X5 SP 0.0 TH 0. Design is performed for all three categories of section described above.0 PRINT MEMB PROP FINISH 1B. user-defined materials 26 — STAAD.0 WT 6.6 Material Properties For specification of material properties.5 * PIPES (CIRCULAR HOLLOW SECTIONS) 10 TA ST PIPE OD 25.LONG LEGS BACK TO BACK 8 TA LD A100X75X10 SP 0. 7.0e6 to E1=200. and shear forces determined from the STAAD. These are used to report the fail or pass status for the members designed. l Warning: Virtualization features of Windows Vista and Windows 7 may require additional files to be modified.Pro analysis. bending moment. etc.7 Member Resistances The member resistance is calculated in STAAD according to the procedures outlined in AS 4100.000 MPa. The nominal member capacity on the other hand refers to the capacity of a member to resist applied loads. Calculated design capacities are compared to corresponding axial.Pro’s default steel material’s E value is 205. going to the “[Material-Metric]” section. The limit state of yielding of the gross section is intended to prevent excessive elongation of the member.4 states that the modulus of elasticity should be taken as 200.6. Two types of design checks are typically performed per AS 4100: l l Nominal section checks Nominal member checks The nominal section capacity refers to the capacity of a cross-section to resists applied loads. and accounts for cross-section yielding and local buckling effects.1 Axial Tension The criteria governing the capacity of tension members are based on two limit states per AS 4100 Section 7.26. and includes checks for global member buckling effects including Euler buckling.ini.Refer Section 5.26.1 Young’s Modulus of Elasticity (E) STAAD. There are a number of options to change this value: l l change the steel material through the input file or GUI for each file created define a new steel material for each file created change the default STAAD. Contact Bentley Technical Support for assistance.Pro for this to take effect. International Design Codes Manual — 27 . 1B. and changing E1=205. 1B. Refer Section 2.Pro metric E value in the file C:/Windows/StaadPro20070.0e6. Restart STAAD.2 of the Technical Reference Manual for further information on the Built-in Material Constants feature. lateral-torsional buckling.1 of the Technical Reference Manual for further information on the Define Material feature.000 MPa. However AS 4100 section 1. 1B. 7. and the f yield stress is based on the y minimum plate yield stress. STAAD calculates the tension capacity of a member based on these two limit states per Cl.Steel Design per AS 4100 . 28 — STAAD.7. KZ. is calculated about both principal x and y axes s and is the capacity to resist cross-section yielding or local buckling and is expressed as the product of the yield stress of the material and the effective section modulus (ref. Through the use of the NSF parameter (see Table 1B.e. It is taken as the lesser of nominal section capacity and nominal member capacity. This value is calculated about both principal x and y axes.2)..1).6.1).3.flange respectively) are different.2. you are required to supply the value of αb (Cl.1B.6). φMb . LY.2). The effective section modulus is a function of section type (i. The nominal section moment capacity. and LZ (see Table 1B. you may specify the net section area. is a function of nominal section capacity and member slenderness reduction factor (Cl.1). Australian Codes . you may specify the net section area. or slender) and minimum plate yield stress f .6. and NSF are applicable for these calculations. Parameters y FYLD.3 Bending Bending capacities are calculated to AS 4100 Section 5. is calculated about the principal x axis only (ref. 1B. net area of the cross section. 1B.2. The f yield stress is based on the minimum plate yield stress. Cl.6. φNc.7. Member moment capacity. Cl.5.2 Axial Compression The compressive strength of members is based on limit states per AS 4100 Section 6.7. φM .2 respectively of AS 4100.3. Critical flange effective cross-section restraints and corresponding design segment and subsegments are used as the basis for calculating capacities.1).2). The allowable bending moment of members is determined as the lesser of nominal section capacity and nominal member capacity (ref.3. perCl. Cl.4. The program automatically calculates the form factor.5.5. φNs.5. and yield stress of the material.Cl.3).7. Here.3). The effective length for the calculation of compressive strength may be provided through the use of the parameters KY. Eccentric end connections can be taken into account using the KT correction factor.1998 The second limit state involves fracture at the section with the minimum effective net area φNt section axial tension capacities are calculated (Cl.7. Note that this parameter is different from that corresponding to tension. The k form factors are f calculated based on effective plate widths per Cl.1 and Cl. noncompact. Nominal section capacity. is a function of form factor (Cl.Pro . compact. Note: For sections where the web and flange yield stresses (fy. Nominal member capacity.web and fy. FU.3) through the ALB parameter (see Table 1B. Through the use of the NSC parameter (see Table 1B.1). The nominal member capacity depends on overall y flexural-torsional buckling of the member (ref.6. the lower of the two yield stresses is applied to both the web and flange to determine the slenderness of these elements. 4 Interaction of Axial Force and Bending Combined section bending and shear capacities are calculated using the shear and bending interaction method as per Cl.5.5 Shear Section web shear capacity.0 or the allowable value provided using the RATIO parameter (see Table 1B. WC. These account for both in-plane and out-of-plane failures. The member strength for sections subjected to axial compression and uniaxial or biaxial bending is obtained through the use of interaction equations. If any of the ratios (for both local Y & Z-axes) exceed 1. CT PFC EA.5. UB. parallel to minor principal y-axis) T-SECTION CHANNEL ANGLE TUBE Calculated for web only BT. If the summation of the left hand side of the equations.4) and member capacity (ref. the ratio of the shear force acting on the cross section to the shear capacity of the section is calculated.7.8.4..1).3-Section Type Shear Checks General Profile Type Australian Section WB.5). UC Shear Checks I-SECTION (i.e. addressed by the above clauses. 1B.0 or the allowable value provided using the RATIO parameter (see Table 1B. Table 1B. UA SHS.3. Note: This check is only carried out where φVv section web shear capacities are calculated.3.1). the member is considered to have FAILed under the loading condition. Cl. φVv . the section is considered to have failed under shear.7.6-1 below highlights which shear capacities are calculated for different profile types.Cl. the adequacy of a member is also examined against both section (ref.8.12. is calculated per Cl. including both shear yield and shear buckling capacities. exceeds 1.11. RHS No checks performed Calculated parallel to both x & y principal axes Per AS 4100 5. Once the capacity is obtained. Refer Table 1B. Table 1B.4 PIPE CHS International Design Codes Manual — 29 .1B.11.6-1 for details. Here. The default parameter values have been selected such that they are frequently used numbers for conventional design.4-Australian Steel Design Parameters Parameter Name CODE Default Value Design Scope Description - Must be specified as AUSTRALIAN to invoke design per AS 4100 1998. These parameters communicate design decisions from the engineer to the program and thus allow the engineer to control the design process to suit an application's specific needs. otherwise the input value is used. This is the way STAAD works for all codes. See section 5.0 Member section constant (refer cl. it is automatically calculated based on TABLE 6. 6.48.Pro does not design sections or members for torsion for AS 4100. 1B. Note: Once a parameter is specified.1998 Note: Only unstiffened web capacities are calculated. Table 1B. PMEMBER Design.3.1 of the Technical Reference Manual.0. 30 — STAAD. 6. ALB 0.3(1).Steel Design per AS 4100 . Australian Codes .8 Design Parameters The design parameters outlined in Table 1B. Design Code to follow. The design scope indicates whether design parameters are applicable for MEMBER Design.7. 1B. Depending on the particular design requirements.3.3.6 Torsion STAAD. Bearing capacities are not considered.Pro .1B.1 are used to control the design procedure. some or all of these parameter values may be changed to exactly model the physical structure. or both.3) If ALB is 0. Stiffened webs are not considered.3(2). its value stays at that specified number until it is specified again. 6. DFF None (Mandatory for deflection check) Analytical members only “Deflection Length”/ Maximum Allowable local deflection. denoting end point for calculation of “deflection length” Maximum allowable depth (Applicable for member selection) Minimum required depth (Applicable for member selection) Ultimate strength of steel.1.1.0 = Perform design for moments at twelfth points along the beam. denoting start point for calculation of “deflection length” Joint No.1. otherwise the input value is used. 5.Parameter Name ALM Default Value Design Scope Description 0. 1.0 [MPa] International Design Codes Manual — 31 .5. it is automatically calculated based cl.1) If ALM is 0.] FU 500. Joint No. DJ1 Start Joint of member DJ2 End Joint of member DMAX 45.0 [in.6. BEAM 0.0 = design only for end moments and those at locations specified by SECTION command.0.0 Moment modification factor (refer cl.0 0.0 [in.] DMIN 0. 0 [MPa] Yield strength of steel.3(2) of AS 4100:1998 0 = at Shear center 1 = At top flange IST 1 KT 1. 2 HR. 7.HW Correction factor for distribution of forces (refer cl.0 KY 1.6.2) K value for general column flexural buckling about the local Y-axis. Used to calculate slenderness ratio. Physical members only Load height position as described in Table 5. K value for general column flexural buckling about the local Z-axis. 32 — STAAD. 3 .0 KZ 1.SR. Used to calculate slenderness ratio. Australian Codes .1B.LW. 4 .CF. 5 . Steel type - 1 .0 LHT 0 LY Member Length Length for general column flexural buckling about the local Y-axis.1998 Parameter Name FYLD Default Value Design Scope Description 250. Used to calculate slenderness ratio.Steel Design per AS 4100 .Pro . Any value greater than 1. Capacity reduction factor Permissible ratio of actual load effect to the design strength.0 is used as the limit for slenderness in compression.0 NSC 1. 0.0 Net section factor for compression members = An / Ag (refer cl. Physical members only Refer to section 1B.0 SGR 0 International Design Codes Manual — 33 . Steel Grade. checks are not explicitly required per AS 4100.9 RATIO 1.0 = normal grade 1. Used to calculate slenderness ratio.0 suppresses the slenderness ratio check.0 Net section factor for tension members.0 or 1.11 for details on the PBRACE parameter. MAIN 0. A value of either 0.0 = high strength grade steel PBRACE None PHI 0.2. Refer to Note a below.1) NSF 1. 6.Parameter Name LZ Default Value Design Scope Description Member Length Length for general column flexural buckling about the local Z-axis. 8. DJ1.Pro .0 output 2.3(1) Output detail 0.0 SKT 1.6.DZ1)2) 34 — STAAD.0 = provide full details of design SKR 1.3(3) A twist restraint factor given in Table 5.DY1)2 + (DZ2 . UNT Member Length Unsupported length in bending compression of the top flange for calculating moment resistance.0 A load height factor given in Table 5.1 Notes a.0 = report only minimum design results 1.6.0 UNB Member Length Unsupported length in bending compression of the bottom flange for calculating moment resistance. DFF.6. and DJ2 – Deflection calculations Compute Delta = SQRT((DX2 .1998 Parameter Name SKL Default Value Design Scope Description 1. Australian Codes .0 = report design strengths in addition to TRACK 0.0 TRACK 0. 1B.Steel Design per AS 4100 .1B.3(2) A lateral rotation restraint factor given in Table 5.DX1)2 + (DY2 . and 3. If there is any variation of the shear force and the load is acting downward determined from shear force variation and load height parameter indicates the load is acting on top flange (flange at the positive local y axis) and restraints at the end of the segment is not FU (FRU) or PU (PRU) Kl is assumed to be 1. 2. The parameters DJ1 and DJ2 should be used to model this situation. c. DJ1 should be 1 and DJ2 should be 4. Thus. This is in accordance with the fact that there is no default value for DFF. It is important to note that unless a DFF value is specified. for all three members here. For example. "Deflection Length" will default to the member length and local deflections will be measured from original member line.Compute Length = distance between DJ1 & DJ2 or. LHT Parameter If the shear force is constant within the segment. between start node and end node. The “Deflection Length” for all three members will be equal to the total length of the beam in this case.4. A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. D = Maximum local deflection for members 1. ALL DJ1 1 ALL DJ2 4 ALL b. If DJ1 and DJ2 are not used. Note: Deflection calculations are not applicable to PMEMBERs. as the case may be. refer to the figure below where a beam has been modeled using four joints and three members. a. If there is any variation of the shear force and the load is acting upward determined from shear force variation and load height parameter indicates the load is acting on top flange (flange at the positive local y axis) and restraints at the end of the segment is not International Design Codes Manual — 35 . longitudinal position of the load is assumed to be at the segment end. b. PARAMETERS DFF 300. STAAD will not perform a deflection check. SGR Parameter AS 4100 defines the values of steel grades that are used as either normal steel or high grade steel.0 MEMBER ALL 36 — STAAD. UA and all UPT sections UB.13 MEMBER ALL BEAM 1. based on maximum thickness of the individual elements of the section. Australian Codes . CHS. Only for shear capacity calculation web thickness is used. Tube. EA. WC. Similarly. Otherwise. UA and all UPT sections Pipe. Tee section cut from WB and 0 (Normal) WC WB.1998 FU (FRU) or PU (PRU) Kl is assumed to be 1. c. EA.Pro. RHS. The following example uses the Member design facility in STAAD. the SGR value will be used to determine the yeild strength and tensile strength values for the steel. UC. Tensile Strength is determined either from FU parameter or from SGR parameter.Steel Design per AS 4100 . CHS. Tee section cut from WB 1 (High) and WC UB.0 as the load acting at the top flange is contributing to stabilize against local torsional buckling. SHS 0 (Normal) 1 (High) 0 (Normal) 1 (High) Note: If a value for the FYLD parameter has been specified.1B. Tee section cut from UB and UC. it is strongly recommended to use the Physical member design capabilities for AS 4100: PARAMETER 1 CODE AUSTRALIAN ALB 0. The following table explains the material values used when either option is specified for a particular shape: Table 1B.0 MEMBER ALL DFF 250. UC.0 MEMBER ALL ALM 1. However. WC. a warning is issued and the yield stress is set to 450 MPa. Tube.5-Steel Grades used for the SGR Parameter Section Type SGR Value Steel Grade Used 300 400 300 350 250 350 WB. then that value will be used. RHS. Warning: A check is introduced to see if yield stress is more than 450 MPa or not. If it is. Tee section cut from UB and UC.Pro . SHS Pipe. 48.0 MEMBER ALL NSC 0.0 MEMBER ALL SKT 1.0 MEMBER ALL IST 2.4 MEMBER ALL DMIN 0. In addition.0 MEMBER ALL UNB 3. Code checking for an analytical member is done using forces and moments at every twelfth point along the beam.DMAX 0.5 MEMBER ALL LY 6.9 MEMBER ALL SGR 1.85 MEMBER ALL KX 0.0 MEMBER ALL MAIN 1.9 MEMBER ALL RATIO 0.2 of the Technical Reference Manual for details the specification of the Code Checking command.5 of the Technical Reference Manual for general information on Code Checking.0 MEMBER ALL TRACK 2. The code checking output labels the members as PASSed or FAILed.9 Code Checking The purpose of code checking is to evaluate whether the provided section properties of the members are adequate for the specified loads as per AS 4100 requirements. location (distance from the start joint) and magnitudes of the governing forces and moments are also printed.0 MEMBER ALL LX 4.0 MEMBER ALL SKL 1.4 MEMBER ALL UNT 6. The extent of detail of the output can be controlled by using the TRACK parameter.0 MEMBER ALL PHI 0.0 MEMBER ALL SKR 1.8 MEMBER ALL CHECK CODE MEMBER ALL 1B. Example of commands for code checking: International Design Codes Manual — 37 . the critical condition. governing load case.25 MEMBER ALL FU 400. Hint: The member selection facility can be used to instruct the program to select a different section if the specified section is found to be inadequate.0 MEMBER ALL FYLD 310.9 MEMBER ALL NSF 1.75 MEMBER ALL KY 1.0 MEMBER ALL KT 0. Refer to Section 2. Refer to Section 5. code checks are performed at section stations positioned at 1/12th points along each analytical member included in the PMEMBER. and then proceeds to calculate the member capacities.9. 38 — STAAD.Steel Design per AS 4100 . however the analytical members can be split so that in effect more stations are checked for a PMEMBER.2. and complete calculations for design. section capacity checks are carried for design actions at that station location. magnitudes of design actions for the most critical cross-section location (distance from the start joint).1B. For these the program searches each side of the station to find adjacent effective restraints and design forces and moments. Color-coded results can also be viewed in the GUI’s Post Processing Beam | Unity Check page. The output reports whether the member has PASSed or FAILed the design checks.Pro . critical load case. as well as the critical condition. However when checking combined actions for the member capacities. For example if a member never goes into tension then no values can be reported in the tension capacity output sections. Australian Codes .9 ALL CHECK CODE MEMB 3 4 Note: Code checking cannot be performed on composite and prismatic sections.1 Physical Members For physical members (PMEMBERs). and adjust as necessary. This is as stipulated in AS 4100 8. 1B. the maximum forces from anywhere along the segment / subsegment being considered are used. For each section station along a PMEMBER. In some cases some of the output will report “N/A” values.2 MEMB 3 4 RATIO 0. The TRACK design parameter can be used to control the level of detail provided in the output. the design actions at the section station are used. The number of stations for PMEMBER Design cannot be altered. It is up to you to determine if these locations cover critical sections for design. Member capacity checks are also carried out for each station. This occurs where a calculation does not apply to a member. Note: When checking combined actions for the section capacities. This allows the program to determine the segment / subsegment that the section station resides in.85 ALL KY 1. Enough section stations should be included to capture all segments / subsegments for checking.1998 UNIT NEWTON METER PARAMETER CODE AUSTRALIAN FYLD 330E6 MEMB 3 4 NSF 0. and can be used to force all members within a user-defined group to take the same section size based on the most critical governing design criteria for all members within that group. or the largest section has been checked.49 of the Technical Reference Manual for information on using this feature.0 detailed level of output for PMEMBER Design uses x and y subscripts to refer to major and minor principal axes respectively. Refer to Section 5.9 ALL SELECT MEMB 3 4 International Design Codes Manual — 39 . Refer to Section 2.Pro local member axes. These differ to STAAD. a member specified initially as a channel will have a channel selected for it. Only section profiles of the same type as modeled are incrementally checked. Refer to Section 5. This may need to be carried out over several iterations. Selection of members whose properties are originally provided from a user table will be limited to sections in the user table. a subsequent analysis and Code Check should be performed to ensure that the final structure is acceptable. Example of commands for member selection: UNIT NEWTON METER PARAMETER FYLD 330E6 MEMB 3 4 NSF 0. For example.6 of the Technical Reference Manual for general information on Member Selection. The design calculations for Member Selection are the same as for Code Checking. In order to correctly account for this.2 MEMB 3 4 RATIO 0.48. Hint: A Fixed Group command is also available. and hence will change the structure’s stiffness matrix.10 Member Selection This process incrementally checks increasing section profile sizes until a size is found that is AS 4100 compliant. Note: Member Selection will change member sizes. This is particularly useful when you want to use the Member Selection feature.4. with the increasing sizes based on a least weight per unit length criteria. where z and y refer to major and minor principal axes.3 of the Technical Reference Manual for details the specification of the Member Selection command. the TRACK 2. but want a group of elements to have the same size.Note: As per AS 4100 1. 1B.85 ALL KY 1. 1B. Refer to Section 5. 1B. single members between two nodes).Pro performed code checks based on single analytical members (i.e.12. members can be manually or automatically formed. automated tensile stress (f ) and yield stress (f ) values based on plate thicknesses.Pro Editor . The term CRITICAL COND refers to the section of the AS 4100 specification which governs the design. PMEMBER Design also has additional features. This implementation remains in place as shown in the example in Section 1B. Refer to Section 1. Traditionally STAAD.07 or higher.16.Pro for checking members against the requirements of AS 4100: a. Australian Codes . even for the design of single analytical members.. Graphical Environment .1998 Note: Composite and prismatic sections cannot be selected.8. Note: This feature requires STAAD.1B.Pro .2 of the Technical Reference Manual for additional information.11 Tabulated Results of Steel Design Results of code checking and member selection are presented in a tabular format.Steel Design per AS 4100 . improved detailed design calculation output. and Thus. l 40 — STAAD. Analytical member method b.4 of the Graphical Environment manual for additional information.1 Modeling with Physical Members Physical Members may be grouped by either of the following methods: l STAAD. u y automated segment / sub-segment design.12 Physical Member Design There are two methods available in STAAD.Directly specify physical members in the input file. it is strongly recommended that PMEMBER Design be used.Pro V8i (SELECTseries 2) build 2007. 1B. Physical member method Herein these are referred to as MEMBER Design and PMEMBER Design respectively. including: l l l l automated steel grades based on section type.Using the tools in the Steel Design toolbar. Physical Member (PMEMBER) Design on the other hand allows you to group single or multiple analytical members into a single physical design member for the purposes of design to AS 4100. “FR”. If the bending moment is zero at the same location as a restraint then the following method is used to determine which flange is critical at the zero moment location: a. Refer AS 4100 5. including available restraint types.Pro’s Modeling mode. User-defined restraints assigned using the PBRACE design parameter are checked to see if they are effective (i. and restraint layout rules. first all user-defined restraints are checked to see if they are applied to the compression flange. Typically the critical flange will be the compression flange. however for another load case may be found not to act on the critical flange. ii. then the compression flange is based on the bending moment at a small increment from that location. The PMEMBER Design uses the following routine to determine effective cross-section restraints for each load case considered: i. then the compression flange is based on the bending moment at a small increment from then end.7 for further information on how user-defined restraints are applied using the PBRACE design parameter. Do not use the Steel Design mode. with those that aren’t ignored. Refer to Section 1B. except for segments with a “U” restraint at one end. International Design Codes Manual — 41 . and found to be ineffective. this must be performed in STAAD. Restraints not applied to the critical flange are ineffective and hence are completely ignored.2. Note: Segment and sub-segment layouts for PMEMBERs may change for different load cases considered for design.Note: When creating PMEMBERs for AS 4100. Some restraints may be effective for one particular load case as they are found to apply to the critical flange. “P” or “PR” restraint are also ignored.4.e. In other words the critical flange can change for each load case considered. The compression flange in step 1 of the routine above is calculated based on the bending moments at the locations of the restraints being considered. If this is the case then any adjacent “L” restraints up to the next “F”. b. regardless of whether they are placed on the critical or non-critical flange. By default PMEMBERs are automatically broken up into design segments and sub-segments based on calculated effective restraints.4. If the zero moment is along the PMEMBER and is a peak value. next a check is made to see if a “U” type restraint is found at either end of the PMEMBER.. in which case it will be the tension flange (as is the case for a cantilever).5). If the zero moment is at the end of the PMEMBER. if they are placed on the critical flange as per AS 4100 5. the PMEMBER Design uses the concept of segment / sub-segment design.2 Segment and Sub-Segment Layout For calculation of member bending capacities about the principal x-axis.12. 1B. For design of cantilevers.1998 c. Table 1B.Steel Design per AS 4100 . Australian Codes .Pro .3 Physical Member Restraints Specification The PBRACE parameter is used to specify the restraint condition along the top and bottom flange of a PMEMBER.1B. These segments are then further divided into sub-segments by effective “L” restraints. Note: If the effective restraints for any load case consist of “U” or “L” restraints only. “FR”. then the stiffer of the restraints at that location is taken.3.4. 1B. the PMEMBER is divided into segments bounded by “F”. Note: Sub-segment lengths are not automatically checked to determine if they provide full lateral restraint as per AS 4100 5. an error will be reported.6-Assumed Order of Restraint Stiffness for Zero Moment Critical Flange Stiffness Most Stiff Restraint Type FR F PR P L U Least Stiff None Once the effective restraints have been determined.2. The stiffness of different restraint types from the most stiff to least stiff are taken as outlined in Table 1B. General Format PBRACE { TOP | BOTTOM } f1 r1 f2 r2 … f52 r52 (PMEMB pmember-list) Where: f is a fraction of the PMEMBER length where restraint condition is being n 42 — STAAD. If neither 1 or 2 above is valid.9-3. “P”.12. the free tip should have user-defined “U” restraints applied to both top and bottom flanges. “PR” or “U” effective restraints. Can only be applied at the ends of design members. U Warning: Both top and bottom flanges can not be unrestrained at the same location (as this is unstable). FR Fully and rotationally restrained Partially and rotationally restrained Continuously The flange is assumed to be restrained continuously supported at that flange up to next restraint location. r 1 Restraint Type Fully restrained Partially restrained Laterally restrained Unrestrained Description F P L Cannot be specified at the ends of design members. r is one of the possible restraint condition as in the following: n Table 1B.0 and 1.specified. and must be applied to both flanges to be effective.0. PR C International Design Codes Manual — 43 . This value is any ratio between 0. For continuously supported flange unbraced length is assumed to be zero.7-Physical Member Restraint Types Designation. 3(2) considering end restraints of the segment.e. tension).1998 Example PBRACE TOP 0. tension). negative local y-axis direction).85 FR 0. then it will be the tension flange (as is the case for cantilever portion at the end).e. FR. “L” restraints are only considered to be effective when positioned on the “critical” flange between “F”.75 L 0.e.75 L 0. segment length is used as UNL and used as L in effective length calculation as per 5. or U restraint specified at both ends. LHT and shear force variation within the segment.1B. for both flanges. P. it is automatically calculated based on table 5..5 L 1. when upward wind loads are dominant (i. α_m is not provided. Design members must have either a F.Steel Design per AS 4100 . Further. “P”. except for segments with U restraint at one end. 0.70 is used as Kr. if an “L” restraint is positioned between a “U” and an “F”. “FR” or “PR” restraint.0 U 0.25 P 0.33 PR 0.0 U PBRACE BOTTOM 0. it is automatically calculated based on Table 5.6.. “P”. it is automatically calculated based on Table 5. it shall be ignored (regardless of whether it is on the critical or non-critical flange).e. If an “L” restraint is positioned on the non-critical flange it shall be completely ignored.. Load Height Position parameter. Australian Codes . Kl is not provided.5 PR 1. “P”. automatic calculation of ALM is done based on moments within the segment.25 F 0..Pro . “FR” or “FP” restraints. l l l l 44 — STAAD. l If UNL is not specified. Kt is not provided. If FR or PR is found at only one of the end.33 PR 0. If SKL i. the critical flange of a segment shall be the top flange (i. the critical flange shall be the bottom flange (i.e..6.85. Kr is not provided.3(1) considering end restraints of the segment and section geometric information and segment length.6. If SKR i. Kr is assumed to be 0. PR.6.e.e.3. positive local y-axis direction). l when gravity loads are dominant (i.... If ALM i. but only if the “L” restraints are deemed to be “effective”.e. if FR or PR is found at both the ends.0 U 0. “FR”. l Design physical members are divided into segments by “F”.3(3) considering restraint conditions are the end of the segment. “PR” or “U” effective section restraints. Segments are further broken down into sub-segments by “L” restraints. If SKT i.5 for a full definition of the critical flange. Typically this will be the compression flange.0 U PMEMB 3 7 Description Refer to AS 4100 Section 5. e. While designing any section of the member. The types of restraints applied to the top and bottom flanges at each location determines the effective section restraints. F. International Design Codes Manual — 45 . These are outlined in the table below: Table 1B. It is not necessary to provide the restraint locations in sequence as the program sorts them automatically. P or F PR V 1 L. F. d. FR or PR L. If PMEMBER list is not provided. effective restraints are searched on each side of the section along the critical flange.8-Restraint Meanings in Critical and Noncritical Flanges Case Flange Restraint on a Critical Flange Restraint on a NonCritical Flange U Nothing L Nothing or U P or F Effective Section Restraint I II 1 2 III 1 U L Nothing P or F U L None F 2 Nothing or U PR or FR P IV 1 Nothing or U PR or FR FR 2 Nothing or U L. c. FR or PR F 2 FR or PR FR Note: The critical flange can change for each load case considered. PMEMBER ends are assumed to be Fully Restrained (F).Notes a. P. all the PMEMBERS are restrained by same configuration. b. Unless specified. P. 1B. Australian Codes - Steel Design per AS 4100 - 1998 1B.12.4 Automated PMEMBER Design Calculations The AS 4100 PMEMBER Design automates many design calculations, including those required for segment / sub-segment design. Table 1B.9-Automated PMEMBER AS 4100 Design Parameters and Calculations Automated Design Calculations PMEMBER Design Parameter ALB Comments α compression b member section constant per AS 4100 6.3.3. α moment m modification factor per AS 4100 5.6.1.1. f tensile strength per u AS 4100 2.1.2. ALM Calculated based on moments distribution for individual segments and sub-segments. Based on nominal steel grade specified using SGR design parameter and section type. Based on nominal steel grade specified using SGR design parameter and section type. Based on section type. FU f yield stress per AS y 4100 2.1.1. FYLD residual stress category for AS 4100 Table 5.2 and AS 4100 Table 6.2.4. correction factor for distribution of forces in a tension member per AS 4100 7.3. Load height position for automated calculation of the kl load height factor per AS 4100 Table 5.6.3(2). IST KT Based on section type and eccentric end connection specified using EEC design parameter. LHT is used for automating calculation of kl load height factors for segments and subsegments, per AS 4100 Table 5.6.3(2). See "Load Height Position" on page 47 for details. LHT Segment and subsegment layout. PBRACE Refer to the Segment and SubSegment Layout section above for details. 46 — STAAD.Pro Automated Design Calculations PMEMBER Design Parameter SGR SKT Comments Nominal steel grade. k twist restraint factor t as per AS 4100 Table 5.6.3(1). k load height factor as l per AS 4100 Table 5.6.3(2). Based on section types. Based on effective end restraints for each segment / sub-segment. SKL Based on effective end restraints for each segment / sub-segment, and LHT design parameter (refer above). Based on effective end restraints for each segment / sub-segment. This is where the distinction between “F” and “FR”, as well as “P” and “PR” is used. k lateral rotation r restraint factor as per AS 4100 Table 5.6.3(3). SKR 1B.12.5 Load Height Position When LHT is set to 1.0 to specify a top flange load height position, STAAD.Pro takes the top to be the positive local y-axis of the member. Note: This may not literally be the top flange for say a column or beam with a beta angle. The local member axes can be viewed in the GUI by selecting “Beam Orientation” in the Diagrams Labels dialog (or Ctrl+O keyboard shortcut). To automate kl using AS 4100 Table 5.6.3(2), the longitudinal position of the load also needs to be considered, i.e., as either “within segment” or “at segment end”. To determine which of these applies, the shear forces at the ends of each design segment / sub-segment is considered. If the shear force is found to have the same direction and magnitude at both ends, it is assumed that loads act at the segment end. If on the other hand the shear force at each end is found to have different directions or magnitudes, loads are assumed to act within the segment. Note: The above method includes an allowance for the self-weight of the member to be considered, as the self-weight always acts through the shear center. The net sum of the end shears is also used to determine if the load is acting in the positive or negative local member y-axis direction. If LHT is set to 1.0 for top flange loading, the net sum is used to determine whether the top flange loading is acting to stabilise or destabilise the member for lateral torsional buckling. Negative local y-axis net loads act to destabilise the International Design Codes Manual — 47 1B. Australian Codes - Steel Design per AS 4100 - 1998 segments / sub-segments, whereas positive local y-axis net loads act to stabilise segments / sub-segments. 1B.12.6 Example PARAMETER 1 CODE AUSTRALIAN DMAX 0.4 PMEMBER ALL DMIN 0.25 PMEMBER ALL KX 0.75 PMEMBER ALL KY 1.0 PMEMBER ALL LX 4.5 PMEMBER ALL LY 6.0 PMEMBER ALL LHT 0.0 PMEMBER ALL NSC 0.9 PMEMBER ALL NSF 1.0 PMEMBER ALL PBRACE BOTTOM 0.0 F 1.0 F PMEMBER ALL PBRACE TOP 0.0 P 0.5 L 1.0 P PMEMBER ALL SGR 0.0 PMEMBER ALL TRACK 2.0 PMEMBER ALL CHECK CODE PMEMBER ALL 48 — STAAD.Pro Section 2 British Codes International Design Codes Manual — 49 50 — STAAD.Pro 2A. British Codes - Concrete Design per BS8110 STAAD.Pro is capable of performing concrete design based on the British code BS8110-1:1997 Structural use of concrete - Part 1: Code of practice for design and construction. Given the width and depth (or diameter for circular columns) of a section, the program will calculate the required reinforcement to resist the forces and moments. Design of members per BS8110-1:1997 requires the STAAD British Std Design Codes SELECT Code Pack. Note: It is strongly recommended that you perform new concrete design using the RC Designer Module. The following is provided to allow old STAAD files to be run. 2A.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to BS8110. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. Default values of commonly used parameters for conventional design practice have been chosen as the basis. Table 2A.1 contains a complete list of available parameters with their default values. Note: Once a parameter is specified, its value stays at that specified number until it is specified again. This is the way STAAD works for all codes. Table 2A.1-British Concrete Design BS 8110 Parameters Parameter Name CODE Default Value Description Must be specified as BRITISH to invoke design per BS8110. Design Code to follow. See section 5.52.2 of the Technical Reference Manual. BRACE 0.0 0.0 = Column braced in both directions. 1.0 = Column unbraced about local Z direction only 2.0 = Column unbraced about local Y direction only 3.0 = Column unbraced in both Y and Z directions International Design Codes Manual — 51 2A. British Codes - Concrete Design per BS8110 Parameter Name CLEAR Default Value 20 mm Description Clearance of reinforcement measured from concrete surface to closest bar perimeter, in current units. Depth of concrete member, in current units. This value default is as provided as YD in MEMBER PROPERTIES. Face of support location at end of beam, in current units. DEPTH YD EFACE 0.0 Note: Both SFACE & EFACE must be positive numbers. ELY 1.0 Member length factor about local Y direction for column design. Member length factor about local Z direction for column design. Concrete Yield Stress / cube strength, in current units Yield Stress for main reinforcement, in current units (For slabs, it is for reinforcement in both directions) Yield Stress for secondary reinforcement a, in current units. Applicable to shear bars in beams Maximum required reinforcement bar size Acceptable bars are per MINMAIN above. ELZ 1.0 30 N/mm 2 FC FYMAIN 460 N/mm 2 FYSEC 460 N/mm 2 MAX MAIN 50mm MINMAIN 8mm Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 16 20 25 32 40 50 MINSEC 8mm Minimum secondary bar size a. Applicable to shear reinforcement in beams MMAG 1.0 Factor by which column design moments are magnified 52 — STAAD.Pro Parameter Name NSE CTION Default Value 10 Description Number of equally-spaced sections to be considered in finding critical moment for beam design. The upper limit is 20. Serviceability checks: 0.0 = No serviceability check performed. 1.0 = Perform serviceability check for beams as if they were continuous. 2.0 = Perform serviceability check for beams as if they were simply supported. 3.0 = Perform serviceability check for beams as if they were cantilever beams. SERV 0.0 SFACE 0.0 Face of support location at start of beam, in current units. (Only applicable for shear - use MEMBER OFFSET for bending ) 0.0 = Orthogonal reinforcement layout without considering torsional moment Mxy slabs only -500 = Orthogonal reinforcement layout with Mxy used to calculate Wood & Armer moments for design. A = skew angle considered in Wood & Armer equations where A is the angle in degrees. SRA 0.0 TRACK 0.0 0.0 = Critical Moment will not be printed with beam design report. Column design gives no detailed results. 1.0 = For beam gives min/max steel % and spacing. For columns gives a detailed table of output with additional moments calculated. 2.0 = Output of TRACK 1.0 List of design sag/hog moments and corresponding required steel area at each section of member International Design Codes Manual — 53 2A. British Codes - Concrete Design per BS8110 Parameter Name WIDTH Default Value ZD Description Width of concrete member, in current units. This value default is as provided as ZD in MEMBER PROPERTIES. 2A.2 Slenderness Effects and Analysis Considerations STAAD provides the user with two methods of accounting for the slenderness effects in the analysis and design of concrete members. The first method is equivalent to the procedure presented in BS8110 Part 1 1985 Section 3.8.2.2 In this section, the code recognizes that additional moments induced by deflection are present and states that these 'secondary' moments are accounted for by the design formula in Section 3.8.3. This is the method used in the design for concrete in STAAD. Alternatively STAAD houses a PDELTA ANALYSIS facility, which allows the effects of these second order moments to be considered in the analysis rather than the design. In a PDELTA analysis, after solving the joint displacements of the structure, the additional moments induced in the structure are calculated. These can be compared to those calculated using the formulation of BS8110. 2A.3 Member Dimensions Concrete members that are to be designed by STAAD must have certain section properties input under the MEMBER PROPERTIES command. The following example demonstrates the required input: UNIT MM MEMBER PROPERTIES *RECTANGULAR COLUMN 300MM WIDE X 450MM DEEP 1 3 TO 7 9 PRISM YD 450. ZD 300. *CIRCULAR COLUMN 300MM DIAMETER 11 13 PR YD 300. * T-SECTION - FLANGE 1000.X 200.(YD-YB) * - STEM 250(THICK) X 350.(DEEP) 14 PRISM YD 550. ZD 1000. YB 350. ZB 250. In the above input, the first set of members are rectangular (450mm depth x 300mm width) and the second set of members, with only depth and no width provided, will be assumed to be circular with 300mm diameter. Note that area (AX) is not provided for these members. If shear area areas ( AY & AZ ) are to be considered in analysis, the user may provide them along with YD and ZD. Also note that if moments of inertias are not provided, the program will calculate them from YD and ZD. Finally a T section can be considered by using the third definition above. 54 — STAAD.Pro 2A.4 Beam Design Beam design includes both flexure and shear. For both types of beam action, all active beam loadings are scanned to create moment and shear envelopes and locate the critical sections. The total number of sections considered is ten, unless that number is redefined with the NSECTION parameter. From the critical moment values, the required positive and negative bar pattern is developed with cut-off lengths calculated to include required development length. Shear design as per BS8110 clause 3.4.5 has been followed and the procedure includes critical shear values plus torsional moments. From these values, stirrup sizes are calculated with proper spacing. The program will scan from each end of the member and provide a total of two shear regions at each, depending on the change of shear distribution along the beam. If torsion is present, the program will also consider the provisions of BS8110 - Part 2 -section 2.4. A table of shear and/or combined torsion is then provided with critical shear. Stirrups not bent up bars are assumed in the design. The example output below shows a sample output of an actual reinforcement pattern developed by STAAD. The following annotations apply: l LEVEL - Serial number of the bar center which may contain one or more bar groups. HEIGHT - Height of bar level from the soffit of the beam in relation to its local y axis. BAR INFO - Reinforcement bar information specifying number of bars and their size. FROM - Distance from the start of the beam to the start of the reinforcing bar. TO - Distance from the start of the beam to the end of the reinforcing bar. ANCHOR - States whether anchorage, either a hook or (STA,END) continuation, is needed at start (STA) or at the end (END). l l l l l l The following is an example TRACK 2.0 beam design output: ==================================================================== B E A M N O. 13 D E S I G N R E S U L T S - FLEXURE LEN - 1500. mm FY - 460. FC - 30. SIZE - 300. X 300. mm LEVEL HEIGHT BAR INFO FROM TO ANCHOR mm mm mm STA END ------------------------------------------------------------------1 29. 4- 8 MM 467. 1500. NO YES 2 264. 4- 8 MM 0. 1158. YES NO REQUIRED REINF. STEEL SUMMARY : ------------------------------SECTION REINF STEEL(+VE/-VE) MOMENTS(+VE/-VE) LOAD(+VE/-VE) ( MM ) (SQ. MM ) (KN-METER) 0. 0.0/ 184.4 0.00/ 19.71 0/ 3 125. 0.0/ 157.2 0.00/ 16.80 0/ 3 250. 0.0/ 129.9 0.00/ 13.89 0/ 3 375. 0.0/ 117.0 0.00/ 10.98 0/ 3 International Design Codes Manual — 55 2A. British Codes - Concrete Design per BS8110 500. 625. 750. 875. 1000. 1125. 1250. 1375. 1500. B E A M 0.0/ 0.0/ 0.0/ 117.0/ 117.0/ 117.0/ 117.0/ 136.3/ 165.3/ 117.0 117.0 117.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00/ 0.00/ 0.00/ 2.15/ 5.25/ 8.36/ 11.46/ 14.57/ 17.67/ 8.07 5.16 2.25 0.00 0.00 0.00 0.00 0.00 0.00 0/ 0/ 0/ 1/ 1/ 1/ 1/ 1/ 1/ 3 3 3 0 0 0 0 0 0 N O. 13 D E S I G N R E S U L T S - SHEAR PROVIDE SHEAR LINKS AS FOLLOWS |----------------------------------------------------------------| | FROM - TO | MAX. SHEAR | LOAD | LINKS | NO. | SPACING C/C | |----------------|------------|------|-------|-----|-------------| | END 1 749 mm | 24.8 kN | 1 | 8 mm | 5 | 187 mm | | 749 END 2 | 24.8 kN | 1 | 8 mm | 5 | 187 mm | |----------------------------------------------------------------| ___ 7J____________________ 1500.X 300.X 300_____________________ 8J____ | | ||========================================================= | | 4No8 H 264. 0.TO 1158 | | | | | 5*8 c/c187 | | | 5*8 c/c187 | | 4No8 H |29. 467.TO 1500 | | | ====================================================|| | | |___________________________________________________________________________| _______________ _______________ _______________ _______________ | | | | | | | | | oooo | | oooo | | oooo | | | | 4T8 | | 4T8 | | 4T8 | | | | | | | | | | | | | | 4T8 | | 4T8 | | 4T8 | | | | oooo | | oooo | | oooo | | | | | | | | | |_______________| |_______________| |_______________| |_______________| 2A.5 Column Design Columns are designed for axial force and biaxial bending at the ends. All active loadings are tested to calculate reinforcement. The loading which produces maximum reinforcement is called the critical load and is displayed. The requirements of BS8110 Part 1 - section 3.8 are followed, with the user having control on the effective length in each direction by using the ELZ and ELY parameters as described in Table 2A.1. Bracing conditions are controlled by using the BRACE parameter. The program will then decide whether or not the column is short or slender and whether it requires additional moment calculations. For biaxial bending, the recommendations of 3.8.4.5 of the code are considered. Column design is done for square, rectangular and circular sections. For rectangular and square sections, the reinforcement is always assumed to be arranged symmetrically. This causes slightly conservative results in certain cases. Below is a typical column design results. 56 — STAAD.Pro Using parameter TRACK 1.0, the detailed output below is obtained. TRACK 0.0 would merely give the bar configuration, required steel area and percentage, column size and critical load case. ==================================================================== C O L U M N N O. 1 D E S I G N R E S U L T S FY - 460. FC -30. N/MM2 SQRE SIZE - 300. X 300. MM, AREA OF STEEL REQUIRED = 940. SQ. MM. BAR CONFIGURATION REINF PCT. LOAD LOCATION ---------------------------------------------------12 10 MM 1.047 1 EACH END (PROVIDE EQUAL NUMBER OF BARS AT EACH FACE) ---------------------------------------------------|BRACED /SLENDER in z E.L.z= 4500 mm (3.8.1.3 & 5)| |BRACED /SLENDER in y E.L.y= 4500 mm (3.8.1.3 & 5)| |END MOMS. MZ1= -12 MZ2= -24 MY1= -15 MY2= -31| |SLENDERNESS MOMTS. KNM: MOMZ= 2 MOMY= 2 | |DESIGN LOADS KN METER: MOM.= 55 AXIAL LOAD= 74| |DESIGNED CAP. KN METER: MOM.= 55 AXIAL CAP.= 74| ---------------------------------------------------- 2A.6 Slab Design Slabs are designed to BS8110 specifications. To design a slab, it must first be modeled using finite elements. The command specifications are in accordance with Section 5.52 of the Technical Reference Manual. A typical example of element design output is shown in below. The reinforcement required to resist the Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist the My moment is denoted as transverse reinforcement ( Fig. 4.1 ). The following parameters are those applicable to slab design: l l l FYMAIN - Yield stress for all reinforcing steel FC - Concrete grade CLEAR - Distance from the outer surface to the edge of the bar. This is considered the same on both surfaces. SRA - Parameter which denotes the angle of the required transverse reinforcement relative to the longitudinal reinforcement for the calculation of Wood & Armer design moments. l Other parameters, as shown in Table 2A.1 are not applicable. 2A.6.1 Wood & Armer equations Ref: R H WOOD CONCRETE 1968 (FEBRUARY) If the default value of zero is used for the parameter SRA, the design will be based on the Mx and My moments which are the direct results of STAAD analysis. The SRA parameter (Set International Design Codes Manual — 57 2A. British Codes - Concrete Design per BS8110 Reinforcement Angle) can be manipulated to introduce Wood & Armer moments into the design replacing the pure Mx, My moments. These new design moments allow the Mxy moment to be considered when designing the section. Orthogonal or skew reinforcement may be considered. SRA set to -500 will assume an orthogonal layout. If however a skew is to be considered, an angle is given in degrees measured anticlockwise (positive) from the element local x-axis to the reinforcement bar. The resulting Mx* and My* moments are calculated and shown in the design format. The design of the slab considers a fixed bar size of 16 mm in both directions with the longitudinal bar being the layer closest to the slab exterior face. Typical output is as follows: ELEMENT DESIGN SUMMARY-BASED ON 16mm BARS ----------------------------------------MINIMUM AREAS ARE ACTUAL CODE MIN % REQUIREMENTS. PRACTICAL LAYOUTS ARE AS FOLLOWS: FY=460, 6No.16mm BARS AT 150mm C/C = 1206mm2/metre FY=250, 4No.16mm BARS AT 250mm C/C = 804mm2/metre ELEMENT LONG. REINF MOM-X /LOAD TRANS. REINF MOM-Y /LOAD (mm2/m) (kN-m/m) (mm2/m) (kN-m/m) -------------------------------------------------------------------------| WOOD & ARMER RESOLVED MOMENTS FOR ELEMENT: 47 UNITS: METRE kN | | LOAD MX MY MXY MX* MY*/Ma* ANGLE | | 1 -10.441 -13.347 1.270 0.000 0.000 0.000 TOP | | 1 -10.441 -13.347 1.270 -11.710 -14.617 0.000 BOTT | | 3 -9.541 -11.995 0.986 0.000 0.000 0.000 TOP | | 3 -9.541 -11.995 0.986 -10.527 -12.981 0.000 BOTT | -------------------------------------------------------------------------47 TOP : 195. 0.00 / 0 195. 0.00 / 0 BOTT: 229. -11.71 / 1 329. -14.62 / 1 2A.7 Shear Wall Design Design of shear walls in accordance with BS 8110 has been added to the features of the program. The program implements the provisions of BS 8110 for the design of shear walls. It performs in-plane shear, compression, as well as in-plane and out-of-plane bending design of reinforcing. The shear wall is modeled by a single or a combination of Surface elements. The use of the Surface element enables the designer to treat the entire wall as one entity. It greatly simplifies the modeling of the wall and adds clarity to the analysis and design output. The results are presented in the context of the entire wall rather than individual finite elements thereby allowing users to quickly locate required information. The program reports shear wall design results for each load case/combination for user specified number of sections given by SURFACE DIVISION (default value is 10) command. The shear wall is designed at these horizontal sections. The output includes the required horizontal and vertical distributed reinforcing, the concentrated (in-plane bending) reinforcing and the link required due to out-of-plane shear. 58 — STAAD.Pro 2A.7.1 Design Parameters START SHEARWALL DESIGN CODE BRITISH shearwall-parameters DESIGN SHEARWALL LIST shearwall-list END The next table explains parameters used in the shear wall design command block above. Note: Once a parameter is specified, its value stays at that specified number until it is specified again. This is the way STAAD works for all codes. Table 2A.2-Shear Wall Design Parameters Parameter Name FYMAIN Default Value 460 Mpa 30 Mpa Description Yield strength of steel, in current units. Compressive strength of concrete, in current units. Minimum size of horizontal reinforcing bars (range 6 mm – 36 mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Maximum size of horizontal reinforcing bars (range 6 mm – 36 mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Minimum size of vertical reinforcing bars (range 6mm – 36mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Maximum size of vertical reinforcing bars (range 6mm – 36mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. FC HMIN 6 HMAX 36 VMIN 6 VMAX 36 International Design Codes Manual — 59 2A. British Codes - Concrete Design per BS8110 Parameter Name Default Value Description Minimum size of vertical reinforcing bars located in edge zones (range 6mm – 36mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Maximum size of vertical reinforcing bars located in edge zones (range 6mm – 36mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Minimum size of links (range 6mm – 16mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Maximum size of links (range 6mm – 16mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Clear concrete cover, in current units. Reinforcement placement mode: EMIN 6 EMAX 36 LMIN 6 LMAX 16 CLEAR 25 mm TWOLAYERED 0 0. single layer, each direction 1. two layers, each direction KSLENDER 1.5 Slenderness factor for finding effective height. 1. Command SET DIVISION 12 indicates that the surface boundary node-to-node segments will be subdivided into 12 fragments prior to finite element mesh generation. 2. Four surfaces are defined by the SURFACE INCIDENCES command. 3. The SUPPORTS command includes the new support generation routine. For instance, the line 2 TO 5GEN PIN assigns pinned supports to all nodes between nodes 2 and 5. As the node-to-node distances were previously subdivided by the SET DIVISION 12 command, there will be an additional 11 nodes between nodes 2 and 5. As a result, all 13 nodes will be assigned pinned supports. Please note that the additional 11 nodes are not individually accessible to the user. They are created by the program to enable the finite element mesh generation and to allow application of boundary constraints. 4. Surface thickness and material constants are specified by the SURFACE PROPERTY and SURFACE CONSTANTS, respectively. 5. The shear wall design commands are listed between lines START SHEARWALL DES and END . The CODE command selects the design code that will be the basis for the design. For British code the parameter is BRITISH. The DESIGN SHEARWALL LIST 60 — STAAD.Pro command is followed by a list of previously defined Surface elements intended as shear walls and/or shear wall components. 2A.7.2 Technical Overview The program implements provisions of section 3.9 of BS 8110:Part 1:1997 and relevant provisions as referenced therein, for all active load cases. The wall is designed as unbraced reinforced wall. The following steps are performed for each of the horizontal sections of the wall set using the SURFACE DIVISION command (see Description above). Checking of slenderness limit The slenderness checking is done for out-of-plane direction. For out-of-plane direction, the wall is assumed to be simply supported. Hence, the provisions of clause 3.9.3.2.2 and 3.9.4.2 are applicable. The default effective height is 1.5 times the clear height. User can change the effective height. The limit for slenderness is as per table 3.23 for unbraced wall, which is taken as 30. Design for in-plane bending (denoted by Mz in the shear wall force output) Walls are assumed to be cantilever beams fixed at their base and carrying loads to the foundation. Extreme compression fibre to centroid of tension (concentrated) reinforcement distance, d, is taken as 0.8 horizontal length of the wall. Flexural design of the wall is carried out in accordance with the provisions of clause no. 3.4.4. The flexural (concentrated vertical ) reinforcing is located at both ends (edges) of the length of the wall. The edge reinforcement is assumed to be distributed over a length of 0.2 times horizontal length on each side. This length is inclusive of the thickness of the wall. Minimum reinforcements are according to table 3.25. Design for in-plane shear (denoted by Fxy in the shear wall force output) Limit on the nominal shear strength, v is calculated as per clause no. 3.4.5.2. Nominal shear strength of concrete is computed as per table 3.8. The design shear stress is computed as per clause no. 3.4.5.12 taking into consideration the effect of axial load. The area of reinforcement is calculated and checked against the minimum area as per clause no. 3.12.7.4. Design for compression and out-of-plane vertical bending This is denoted by Fy and My respectively in the shear wall force output. International Design Codes Manual — 61 2A. British Codes - Concrete Design per BS8110 The wall panel is designed as simply supported (at top and bottom), axially loaded with outof-plane uniform lateral load, with maximum moments and deflections occurring at midheight. Design is done as per clause no. 3.8.4 for axially loaded column with uni-axial bending. The minimum reinforcement percentage is as per table 3.25. The maximum reinforcement percentage of vertical reinforcement is as per clause no. 3.12.6.3. Links if necessary are calculated as per the provisions of clause 3.12.7.5. Design for out-of-plane shear (denoted by Qy in the shear wall force output) The out-of-plane shear arises from out-of-plane loading. The design shear stress is calculated as per 3.4.5.2 and shear strength of concrete section is calculated as per table 3.8 considering vertical reinforcement as tension reinforcement. Shear reinforcements in the form of links are computed as per table 3.7 and the provisions of clause 3.12.7.5. Design for out-of-plane horizontal bending (denoted by Mx in the shear wall force output) The horizontal reinforcement already calculated from in-plane shear is checked against the whole section subjected to out-of-plane bending and axial load. The axial load in this case is the in-plane shear. The section is again designed as axially loaded column under uni-axial bending as per the provisions of clause 3.8.4. Extra reinforcement in the form of horizontal bars, if necessary, is reported. 2A.7.3 Example The following example starts from the definition of shear wall and ends at the shear wall design. . . SET DIVISION 12 SURFACE INCIDENCES 2 5 37 34 SUR 1 19 16 65 68 SUR 2 11 15 186 165 SUR 3 10 6 138 159 SUR 4 . . . SURFACE PROPERTY 62 — STAAD.Pro 1 TO 4 THI 18 SUPPORTS 1 7 14 20 PINNED 2 TO 5 GEN PIN 6 TO 10 GEN PIN 11 TO 15 GEN PIN 19 TO 16 GEN PIN . . SURFACE CONSTANTS E 3150 POISSON 0.17 DENSITY 8.68E-005 ALPHA 5.5E-006 . . START SHEARWALL DES CODE BRITISH UNIT NEW MMS FC 25 FYMAIN 460 TWO 1 VMIN 12 HMIN 12 EMIN 12 DESIGN SHEA LIST 1 TO 4 END 2A.7.4 Shear Wall Design With Opening The Surface element has been enhanced to allow design of shear walls with rectangular openings. The automatic meshing algorithm has been improved to allow variable divisions along wall and opening(s) edges. Design and output are available for user selected locations. Shear walls modeled in STAAD.Pro may include an unlimited number of openings. Due to the presence of openings, the wall may comprise up with different wall panels. Shear wall set-up Definition of a shear wall starts with a specification of the surface element perimeter nodes, meshing divisions along node-to-node segments, opening(s) corner coordinates, and meshing International Design Codes Manual — 63 . .. then the corresponding division number is set to the default value (=10. . .) - od1. . The output is provided for sections located between division segments. SURFACE INCIDENCE n1. sdj or the od1.. .. .. or as previously input by the SET DIVISION command).. .. odk list does not include all node-tonode segments. 64 — STAAD.. ni SURFACE s DIVISION sd1.Pro .....Concrete Design per BS8110 divisions of four edges of the opening(s). sdj - number of divisions for each of the node-to-node distance on the surface perimeter. sdj RECOPENING x1 y1 z1 x2 y2 z2 x3 y3 z3 x4 y4 z4 DIVISION od1. or if any of the numbers listed equals zero..... odk - coordinates of the corners of the opening.number of divisions along Y axis. ni - node numbers on the perimeter of the shear wall... ... Default locations for stress/force output. For example.. yd .. The general format of the command is as follows: PRINT SURFACE FORCE (ALONG ξ) (AT a) (BETWEEN d1.. divisions along edges of the opening.. if the number of divisions = 2.number of divisions along X axis. then the output will be produced for only one section (at the center of the edge).. Note: xd and yd represent default numbers of divisions for each edge of the surface where output is requested. and design output are set as follows: SURFACE DIVISION X xd SURFACE DIVISION Y yd Where: xd . Stress/force output printing Values of internal forces may be printed out for any user-defined section of the wall. sd1.. s - surface ordinal number. design..si Where: ξ - local axis of the surface element (X or Y). British Codes .. x1 y1 z1 (. d2) LIST s1. . odk Where: n1.2A. Note: If the sd1.. ) DESIGN SHEARWALL (AT c) LIST s TRACK tr International Design Codes Manual — 65 . ptype . the output is generated based on full cross-section width. delineating a fragment of the full cross-section for which the output is desired. the negative range is to be entered. d2 - coordinates in the direction orthogonal to ξ. General syntax of the design command is as follows: START SHEARWALL DESIGN (. ..WALL x1 y1 z1 (.si - list of surfaces for output generation ** The range currently is taken in terms of local axis.** s1.. If command AT is omitted... If the local axis is directed away from the surface. j - ordinal panel number. If the BETWEEN command is omitted. Definition of wall panels Input syntax for panel definition is as follows: START PANEL DEFINITION SURFACE i PANEL j ptype x1 y1 z1 x2 y2 z2 x3 y3 z3 x4 y4 z4 ENDPANEL DEFINITION where: i - ordinal surface number. Number of sections will be determined from the SURFACE DIVISION X or SURFACE DIVISION Y input values... d1. Note: If command ALONG is omitted. direction Y (default) is assumed.. Shear wall design The program implements different provisions of design of walls as per code BS 8110.a - distance along the ξ axis from start of the member to the full crosssection of the wall.) - coordinates of the corners of the panel Note: Design of COLUMN and BEAM panels is currently not available. output is provided for all sections along the specified (or default) edge. full design output will be generated. Design is performed for the specified horizontal full cross-section. The area of horizontal and vertical bars provided along edges of openings is equal to that of the respective interrupted bars.2A. British Codes .indicates a basic set of results data (default). the design proceeds for all cross sections of the wall or panels. Design is performed for all panels. located at a distance c from the origin of the local coordinates system. 66 — STAAD. a. b.Pro . defined by the SURFACE DIVISION X or SURFACE DIVISION Y input values.Concrete Design per BS8110 ENDSHEARWALL DESIGN Parameter TRACK specifies how detailed the design output should be: 0 . for the cross-section located at a distance c from the start of the panel. Panels have been defined. 1 . No panel definition. as applicable. If the command AT is omitted. If opening is found then reinforcement is provided along sides of openings. Accordingly. composite sections. The effective length for the v-v axis.1 General The design philosophy embodied in BS5950:2000 is built around the concept of limit state design. The following diagram shows the axes for angles which have been defined with either an ST or RA specification and is connected by its longer leg (i. Incorporating Corrigendum No.e..Pro is capable of performing steel design based on the British code BS 5950-1:2000 Structural use of steelwork in building . tubes. Appropriate safety factors are used so that the chances of limits being surpassed are acceptably remote. members are proportioned to resist the design loads without exceeding the limit states of strength and stability. See Section 2B. tees. See section 2B. steel tables for both hot rolled and hollow sections are built into the program for use in specifying member properties as well as for the actual design process. Lvv. columns. British Codes . This procedure is controlled by the designer in specification of allowable member depths. Single Angle Sections Angle sections are un-symmetrical and when using BS 5950:2000 table 25 you must consider four axes: two principal.Pro 2006 and later have the additional option to design tapered I shaped (wide flange) beams according to Annex G of BS5950. The a-a and b-b axes are determined by which leg of the angle is fixed by the connection and should be specified using the LEG parameter. International Design Codes Manual — 67 . piles.4 for information regarding the referencing of these sections.13 for a complete description. the most economic section is selected on the basis of the least weight criteria.C.2B.Rolled and welded sections. The code checking portion of the program checks that code requirements for each selected section are met and identifies the governing criteria.serviceability and ultimate. used today in most modern steel design codes. 2B. STAAD. there is a provision for user provided tables. The effective length in the a-a axis is taken as LY · KY and the effective length in the b-b axis as LZ · KZ. channels. desired section type or other such parameters. u-u and v-v and two geometric. 1. a-a axis is parallel to the longer leg).6 for more information on the LEG parameter. In the STAAD implementation of BS5950:2000. The primary considerations in ultimate limit state design are strength and stability while that in serviceability limit state is deflection. beams with cover plates. see section 5B. In addition to universal beams. is taken as the LVV parameter or LY · KY. joists. Structures are designed and proportioned taking into consideration the limit states at which they become unfit for their intended use.Steel Design per BS5950:2000 STAAD.Part 1: Code of practice for design . and angles.S. a-a and b-b. Two major categories of limit state are recognized . Design of members per BS 5950-1:2000 requires the STAAD British Std Design Codes SELECT Code Pack. pipes. if not specified. The complete B. Dynamic analysis may also be performed and the results combined with static analysis results.7. 68 — STAAD. A complete listing of the sections available in the built-in steel section library may be obtained by using the tools of the graphical user interface.Pro . the steel section library available in STAAD may be used. 2B. Refer to Section 1. Almost all BSI steel sections are available for input.2 Analysis Methodology Elastic analysis method is used to obtain the forces and moments for design. British Codes .3 Member Property Specifications For specification of member properties. For more information on these facilities. refer to Section 1. the properties are also used for member design. Since the shear areas are built into these tables. except for GENERAL or PRISMATIC sections.Steel Design per BS5950:2000 Figure 2B.Axis orientation for single angles ST angle and USER table angles RA angle 2B. Member properties may also be specified using the User Table facility. regular stiffness analysis or P-Delta analysis may be specified. Depending upon the analysis requirements. shear deformation is always considered during the analysis of these members.4 Built-In Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. Any user-defined section may be specified.1 . These properties are stored in a database file. Analysis is done for the primary and combination loading conditions provided by the user. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations. 2B.7 the STAAD Technical Reference Manual. The next section describes the syntax of commands used to assign properties from the built-in steel table.2 of the Technical Reference Manual for additional information.2B. If called for. g. 20 TO 30 TA ST UB305X165X54 33 36 TA ST UC356X406X287 100 102 106 TA ST UP305X305X186 2B. Columns. The following examples illustrate the designation scheme.4. 10 TO 20 TA ST JO152X127 1 2 TA ST JO127X114A 2B. with or without spacing between them.4.1 Universal Beams. The same designation scheme as in BSI tables may be used with the weight omitted. columns and pile sections are available.4. The designation is similar to that of the joists. (specifies a double channel with a spacing of 5 length units) Note: Face-to-face double channels can not be used in a CHECK CODE command. In those cases where two joists have the same specifications but different weights.Following are the descriptions of different types of sections available: 2B. and Piles All rolled universal beams.3 Channels All rolled steel channel sections from the BSI table have been incorporated in STAAD.) 51 52 53 TA D CH152X89 70 TO 80 TA D CH305X102 SP 5.. etc. International Design Codes Manual — 69 . The letter "D" in front of the section name will specify a double channel (e. D CH203X89. 10 TO 15 TA ST CH305X102 55 57 59 61 TA ST CH178X76 2B. the lighter section should be specified with an "A" at the end.4 Double Channels Back-to-back double channels.4. D CH102X51. are available.2 Rolled Steel Joists Joist sections may be specified as they are listed in BSI-80 with the weight omitted. Steel Design per BS5950:2000 2B. If the local STAAD y-axis corresponds to the V-V axis in the tables.5 Tee Sections Tee sections are not input by their actual designations. 14 TO 20 TA LD UA200X200X16 SP 1. but instead by referring to the universal beam shapes from which they are cut. 35 TO 45 TA RA UA200X150X18 2B.7 Double Angles Short leg back-to-back or long leg back-to-back double angles can be specified by inputting the word SD or LD.4.5 23 27 TA SD UA80X60X6 "SP" denotes spacing between the individual angle sections. Note. use PIP followed by the numerical value of diameter and thickness of the section in mm omitting the decimal section of the 70 — STAAD. in front of the angle size. 54 55 56 TA T UB254X102X22 (tee cut from UB254X102X22) 2B. British Codes . respectively.4.Pro . type specification "RA" (reverse angle) may be used.4.19 User Steel Table Specification) 2B. For example. RA specification. Note: If the section is defined from a Double Angle User Table. then the section properties must be defined with an 11th value which defines the radius of gyration about an individual sections’ principal v-v axis (See Technical Reference Manual.4. that only angles specified with an RA specification can be designed. ST specification or reversed angle.2B.6 Angles All equal and unequal angles are available for analysis. however. The standard angle section is specified as follows: 15 20 25 TA ST UA200X150X18 This specification may be used when the local STAAD z-axis corresponds to the V-V axis specified in the steel tables.8 Pipes (Circular Hollow Sections) To designate circular hollow sections from BSI tables. either a standard. 5. In case of an equal angle. Two types of specifications may be used to describe an angle section. For example. either LD or SD will serve the purpose. 10 15 TA ST PIP213. 1 TO 9 TA ST PIPE OD 25. AND A WALL THICKNESS OF 0. 6 TA ST TUBE DT 8. For example.value provided for diameter.0 Tubes.9 Rectangular or Square Hollow Sections (Tubes) Designation of tubes from the BSI steel table is illustrated below: Figure 2B.2 .0 ID 20.BSI tube nomenclature Example: 15 TO 25 TA ST TUB160808.0 WT 6. A WIDTH OF 6.2 (specifies a 21. Width and Thickness) and not by any table designations. like pipes.4. of 20 in current length units) Only code checking and no member selection will be performed if this type of specification is used.5 LENGTH UNITS) Note: Only code checking and no member selection is performed for TUBE sections specified this way. The following example will illustrate the designation. 2B.0 (specifies a pipe with outside dia.5 (A TUBE THAT HAS A HEIGHT OF 8. of 25 and inside dia.3 mm dia. can also be input by their dimensions (Height.0 TH 0. International Design Codes Manual — 71 .2 mm wall thickness) Circular hollow sections may also be provided by specifying the outside and inside diameters of the section. pipe with 3. 9. however.2B. 2B. slender.6 of the code. Class 3. British Codes .1 Axial Tension In members with axial tension. 2B. BS5950 recommends the use of a 'stress reduction factor' to reduce the design strength. Compression resistance is determined according to the compressive strength. the tensile load must not exceed the tension capacity of the member. this option can be included by specifying a MAIN parameter. limiting slenderness of the member and appropriate design strength. Based on data collected from extensive research.see Table 2B. generally compression members are no longer required to be checked for slenderness limitations. a slenderness limit of 50 is still applied on double angles checked as battened struts as per clause 4. proceeding with member selection or code check accordingly.1). the appropriate design strength and the relevant strut characteristics. plastic. semi-compact or Class 4. careful consideration must be given to the influence of local buckling on moment capacity.Steel Design per BS5950:2000 2B. it has been determined that sections such as tubes with low residual stresses and Universal Beams and Columns are of intermediate performance.0 is present but may be altered by changing the input value .Pro .2 Compression Compression members must be designed so that the compression resistance of the member is greater than the axial compressive load. This factor is again a function of the geometry of the section and is automatically determined by STAAD for use in the design process. compact.5. This is a significant departure from the standard practice followed in BS449.5 Member Capacities The basic measure of capacity of a beam is taken as the plastic moment of the section. Note. These research observations are incorporated in BS5950 through the use of four strut curves together with a selection of tables to indicate which curve to use for a particular case. 72 — STAAD. Class 2. STAAD calculates the tension capacity of a given member per this procedure. based on a user supplied net section factor (NSF-a default value of 1. sections are classified as either Class 1. Compression strength for a particular section is calculated in STAAD according to the procedure outlined in Annex C of BS5950 where compression strength is seen to be a function of the appropriate Robertson constant ( representing Strut Curve) corresponding Perry factor. which is a function of the slenderness of the gross section. for slender sections. which governs the decision whether to use the plastic or the elastic moment capacity.5. in which the limiting condition was attainment of yield stress at the extreme fibres of a given section. To assist this. With the introduction of the plastic moment as the basic measure of capacity. Strut characteristics take into account the considerable influence residual rolling and welding stresses have on column behavior. The tension capacity of the member is calculated on the basis of the effective area as outlined in Section 4. It has been found that I-shaped sections are less sensitive to imperfections when constrained to fail about an axis parallel to the flanges. In addition. A departure from BS5950:1990. STAAD is capable of determining the section classification for both hot rolled and built up sections. The section classification is a function of the geometric properties of the section. BS5950 does not have any slenderness limitations for tension members.7. 2 is applied based on effective tension capacity. For plastic or compact sections with high shear loads. For members with axial tension and moment. 2B.3 Axially Loaded Members With Moments In the case of axially loaded members with moments. which for compact/plastic sections may be more critical.8. If this is the case.6 to calculate the appropriate moment capacities of the section.3. If the section is plastic or compact. the plastic modulus has to be reduced to accommodate the shear loads. International Design Codes Manual — 73 .3. COMPRESSION will be the critical condition reported despite the presence of moments.2) and the Member Buckling Resistance check (4.5 Lateral Torsional Buckling Since plastic moment capacity is the basic moment capacity used in BS5950. STAAD also carries out cross checks for compression only. the elastic moment is used. For semi-compact or slender sections. can be specified by the user or x y yx calculated by the program. the interaction formula as outlined in section 4.3. also 4. The purpose of this elastic limitation is to prevent plasticity at working load.3. Hence.5 and Annex H3 if appropriate. considering the appropriate shear area for the section specified.4 Shear A member subjected to shear is considered adequate if the shear capacity of the section is greater than the shear load on the member.8. lateral torsional buckling must be considered carefully. two principal interaction formulae must be satisfied – Cross Section Capacity check (4.1).5 and 4. the moment capacity of the member must be calculated about both principal axes and all axial forces must be taken into account.3.5.8.8. members are likely to experience relatively large deflections. As noted in the code.2B.5.2) and Annex I1 for stocky members. plastic moment capacities will constitute the basic moment capacities subject to an elastic limitation. 2B. may result in severe serviceability limit state. Three types of approach for the member buckling resistance check have been outlined in BS5950:2000 . This effect. coupled with lateral torsional buckling.4.3. the more exact approach (4. It has been found.3. the more exact approach may be more conservative than the simplified approach.3 ). m m and m . The STAAD implementation of BS5950 incorporates the procedure outlined in section 4. that this is not always the case and STAAD therefore performs both checks.2. Shear capacity is calculated in STAAD using the procedure outlined in section 4. comparing the results in order that the more appropriate criteria can be used. Additionally the equivalent moment factors.8. Members subject to biaxial moments in the absence of both tensile and compressive axial forces are checked using the appropriate method described above with all axial forces set to zero. For members with axial compression and moment.2.the simplified approach (4.5. in cases where neither the major axis nor the minor axis moment approaches zero. however.2. which is determined as a function of the loading configuration and the nature of LT the load (stabilizing. its value stays at that specified number till it is specified again.Additional Provisions Rectangular Hollow sections are treated in accordance with S. AD Depth at end/2 Distance between the reference axis and the axis of restraint.6 RHS Sections .I. etc). See G.. and the equivalent moment factor. Table 2B.48.2.2 has been implemented for all sections with the exception of angles.1 along with their default values. the following expressions are used to calculate the reduced plastic moduli: For n ≥ 2t(D-2t)/A S rx = A 2D (B − t ) 1 − n 4(B − t ) A 2 + n − 1 For n ≥ 2t(B-2t)/A S ry = A 2B (D − t ) 1 − n 4(D − t ) A 2 + n − 1 2B. for a member subjected to moments about the major axis.5. the resistance moment is given as a function of the elastic critical moment. and limiting equivalent slenderness. which are calculated within the program. destabilizing.1-British Steel Design BS5950:2000 Parameters Parameter Name Default Value Description Must be specified as BS5950 CODE Design Code to follow. See section 5. According to this procedure. In Annex B. the procedure outlined in Annex B.2B. Perry coefficient. Note: Once a parameter is specified.2. British Codes .C.3 74 — STAAD. m .6 Design Parameters Available design parameters to be used in conjunction with BS5950 are listed in table 2B.Steel Design per BS5950:2000 The procedure to check for lateral torsional buckling as outlined in section 4.3 has been incorporated in the STAAD implementation of BS5950.Pro . 2B. For calculation of the buckling resistance moment. recommendations in cases when the plastic axis is in the flange.1 of the Technical Reference Manual. the 'equivalent uniform moment' on the section must be less than the lateral torsional buckling resistance moment. This is the way STAAD works for all codes. In such cases. 0. 3. Clause checks at one location. Same as BEAM = 1. Calculate forces and moments at 12th points along the member. Establish the location where Mz is the maximum. Deflection check based on the principle that maximum deflection is of the cantilever type (see note below) BEAM 3. 1. 1.0 but additional checks are carried out for each end. Deflection check method. Calculate moments at 12th points along the member.Parameter Name Default Value Description Beam divisions 0.0 CAN 0 International Design Codes Manual — 75 . See Note 1 below. Clause checks at each location including the ends of the member. 2. Use the forces and moments at that location. Design only for end moments or those locations specified by the SECTION command. Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2. 8.3.Steel Design per BS5950:2000 Parameter Name Default Value Description Moment calculation: 1. 1.axis. denoting end point for calculation of "Deflection Length. To calculate Mbs (simple) as per Clause 4.8.0) "Deflection Length" / Maxm.3. 2.2.0 = Fail ratio uses MAX of 4. DJ1 Start Joint of member DJ2 End Joint of member 100.5 (continuous) to calculate Mb.7 as opposed to Mb.3.8.1. Usually. K factor value in local z . Usually." See Note 1 below. ESTIFF 0.8.3.3. allowable local deflection See Note 1d below.0 DFF None (Mandatory for deflection check.Pro .0 76 — STAAD.2B. denoting starting point for calculation of "Deflection Length.3.1 and 4.0 KY 1.0 = Fail ratio uses MIN of 4.1." See Note 1 below.0 K factor value in local y . DMAX * DMIN * Maximum allowable depth Minimum allowable depth Clauses 4.3.2.2 0.axis. 4.7.2.3.3.3. Joint No. TRACK 4. this is the major axis. KZ 1. and Annex I1 checks.8.3.0cm 0.0 cm Joint No. 4.3.8. and Annex I1 checks. BS5950 per clause B. British Codes . this is the minor axis. CB 1. axis (current units) to calculate (KZ)(LZ)/Rzz slenderness ratio.4 Equivalent moment factor for major axis flexural buckling as defined in clause 4. LEG 0.3. LY * Member Length Length in local y .Parameter Name Default Value Description Valid range from 0 – 7 and 10. International Design Codes Manual — 77 .3.0 NSF 1.4 Equivalent moment factor for minor axis flexural buckling as defined in clause 4.0 = Infinity Any other value used in the calculations.4 Equivalent moment factor for minor axis lateral flexural buckling as defined in clause 4.0 MYX 1.3.0 0.8.axis (current units) to calculate (KY)(LY)/Ryy slenderness ratio. Length in local z .0 MX 1.3. Transverse stiffener spacing (‘a’ in Annex H1) LZ * Member Length MLT 1.0 PNL * 0.4 Net section factor for tension members.3.8.0 Maximum of Lyy LVV * and Lzz (Lyy is a term used by BS5950) Used in conjunction with LEG for Lvv as per BS5950 table 25 for double angles. The values correspond to table 25 of BS5950 for fastener conditions.0 MY 1.8.8.3. See note 6 below.3. Equivalent moment factor for lateral torsional buckling as defined in clause 4.3. See note 2 below. effective length/ radius of gyration.0 Permissible ratio of the actual capacities. Controls the sections to try during a SELECT process.0 78 — STAAD. British Codes .2B.0 = Try only those sections with a similar name as original.. for a given axis: 0. (250) 3.0 = Slenderness not performed. MAIN 0. even if there are HEM’s in the same table.Steel Design per BS5950:2000 Parameter Name PY * Default Value Set according to steel grade (SGR) Description Design strength of steel Slenderness limit for members with compression forces.g. 0.0 = Try every section of the same type as original 1. SAME** 0. e.0 1.0 = Secondary member.0 = Bracing etc (350) RATIO 1. then only HEA sections will be selected.0 = Main structural member (180) 2. if the original is an HEA 100.Pro . 0 = Grade S 460 3.Parameter Name Default Value Description Identify Section type for section classification 0.0 = Built up Section 2.0 International Design Codes Manual — 79 .0 = Cold formed section Specifies a load case number to provide the sway loading forces in clause 4.3.0 1.8.0 = Suppress all member capacity info.0 = As per GB 1591 – 16 Mn 0.0 = Elastic stress analysis TB 0. 2. 1.0 1.0 = Plastic stress analysis Output details 0.0 = Print detailed design sheet.0 1.0 = Grade S 355 2.0 = Deflection Check (separate check to main select / check code) TRACK 0.0 = Print all member capacities.0 = Grade S 275 SWAY none SGR 0.0 = Rolled Section SBLT 0.3. 4.4 (See additional notes) Steel Grade per BS4360 0. When performing the deflection check. and DJ2 – Deflection a.2B. you can choose between two methods. Welding on both sides (except pipes and tubes) UNF 1. DJ1.0 = Open sections.0 UNL * Member Length 1. If the CAN parameter is set to 1. the check will be based on cantilever style deflection.6. British Codes .0 open * current units must be considered. Let (DX1. CAN. Local displacement is described in Section 5. defined by a value 0 for the CAN parameter.44 of the Technical Reference Manual.Steel Design per BS5950:2000 Parameter Name Default Value Description Factor applied to unsupported length for Lateral Torsional Buckling effective length per section 4.0 = Closed sections. if the original section is an equal angle. Unsupported Length for calculating Lateral Torsional Buckling resistance moment section 4.3.3. see AISC steel design 1. the start node of the 80 — STAAD. Note: There was an NT parameter in STAAD.6.0 closed WELD 2. **For angles.7 of BS5950. is based on the local displacement. The first method.1 Notes 1. Welding on one side only (except for webs of wide flange and tee sections) 2.Pro 2005 build 1003 which is now automatically calculated during the design as it is load case dependant. 2B. DZ1) represent the nodal displacements (in global axes) at the node defined by DJ1 (or in the absence of DJ1.7 of BS5950.Pro .6. DY1. Weld Type. then the selected section will be an equal angle and vice versa for unequal angles. for all three members here. However.DZ1)2) Compute Length = distance between DJ1 & DJ2 or. (DX2.member). This is in accordance with the fact that there is no default value for DFF. 2. Compute Delta = SQRT((DX2 .DY1)2 + (DZ2 . The parameters DJ1 and DJ2 should be used to model this situation. The above parameters may be used in conjunction with other available parameters for steel design. PARAMETERS DFF 300. d.DX1)2 + (DY2 . 2. as the case may be. "Deflection Length" will default to the member length and local deflections will be measured from original member line. dff = L/Delta Ratio due to deflection = DFF/dff b. It is important to note that unless a DFF value is specified. between start node and end node. International Design Codes Manual — 81 . Similarly. For example. If CAN = 0. if CAN is specified a value 1. deflection length is defined as the length that is used for calculation of local deflections within a member. This table concerns the fastener restraint conditions for angles. D = Maximum local deflection for members 1. tee sections and channels for slenderness. It may be noted that for most cases the “Deflection Length” will be equal to the length of the member. in some situations. and 3. DJ1 should be 1 and DJ2 should be 4. The “Deflection Length” for all three members will be equal to the total length of the beam in this case. ALL DJ1 1 ALL DJ2 4 ALL c. STAAD will not perform a deflection check. double angles. e. DZ2) represent the deflection values at DJ2 or the end node of the member. the “Deflection Length” may be different. Thus. If DJ1 and DJ2 are not used. LEG – follows the requirements of BS5950 table 28. DY2. A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. Then. refer to the figure below where a beam has been modeled using four joints and three members. 0 2. the slenderness is calculated for the geometric axes.10.0 2.2 or more rows of bolts (b) .0 7. a-a and b-b as well as the weak v-v axis.7.0 Leg short leg LEG Parameter 1.0 For single angles.0 0.2B.0 b. The effective lengths of the geometric axes are defined as: La = KY * KY 82 — STAAD.0.1 row of bolts 4.0 0.0 1.2.5 Tee Sections (a) .0 long leg short leg 3.0 3.2 bolts short leg long leg (d) . Long Leg = 2. British Codes .0.1 row of bolts 0. 2 Bolts: Short leg = 1.4 Channels (b) .2 Single Angle: a.0 1. 1 Bolt: Short Leg = 0.0 long leg long leg 6.7.Pro .10. channel and tee sections are specified in BS 5950 table 25 depending on the connection provided at the end of the member.10. To define the appropriate connection.7.2 Single Angle (b) .7.10. Long Leg = 3.1 bolts long leg short leg (a) .3 Double Angles (c) .10.2 bolts 4. a LEG parameter should be assigned to the member.0 The slenderness of single and double angle.LEG Parameter values Clause Bold Configuration (a) .1 bolts 4. The following list indicates the value of the LEG parameter required to match the BS5950 connection definition: Clause 4.1 bolts short leg (a) .0 1.2 bolts long leg short leg (b) .7.2 or more rows of bolts 4.0 4.0 0.0 5.Steel Design per BS5950:2000 The following values are available: Table 2B. 0 for MX.19) an eleventh value.4 and 1. 1. usually with a different load list to the main code check. They are supplied along with or instead of UNF.0 for MLT. Otherwise the value of PY will be set according to the stipulations of BS5950 table 9 in which the design strength is seen as a function of cross sectional thickness for a particular steel grade (SGR parameter) and particular element considered. For double angles. 5. LY and LZ should be real numbers greater than zero in current units of length. and DJ2 set. KY and KZ (which are factors. TRACK 4. PY – Steel Design Strength The design parameter PY should only be used when a uniform design strength for an entire structure or a portion thereof is required. should be supplied at the end of the ten existing values vv corresponding to the radius of gyration of the single angle making up the pair. MYX.0 causes the design to carry out a deflection check. In addition. (Technical Reference Manual section 5. if using double angles from user tables. LY.0. 4. not lengths) to define lateral torsional buckling and compression effective lengths respectively. Generally speaking this option is not required and the program should be allowed to ascertain the appropriate value.44 and 1. MY and MYX and 0. TRACK – Control of Output Formats When the TRACK parameter is set to 0.Lb = KZ * LZ The slenderness calculated for the v-v axis is then used to calculate the compression strength p for the weaker principal axis (z-z for ST angles or y-y for RA specified c angles). member capacities will be printed in design related output (code check or member selection) in kilonewtons per square meter. The maximum slenderness of the a-a and b-b axes is used to calculate the compression strength p for the stronger principal axis. Please note that both UNL or UNF and LY or KY values are required even though they are often the same values. MX.0.0. UNL. 6. by setting the LEG parameter to 10. DJ1. The former relates to compression flange restraint for lateral torsional buckling while the latter is the unrestrained buckling length for compression checks. slenderness is calculated for the two principal axes y-y and z-z only. the LVV parameter is available to comply with note 5 in table 25. c Alternatively for single angles where the connection is not known or Table 25 is not appropriate. r . 3. International Design Codes Manual — 83 . and LZ – Relevant Effective Length The values supplied for UNL. MY. The members that are to be checked must have the parameters DFF. and MLT – Equivalent Moment Factors The values for the equivalent moment factors can either be specified directly by the user as a positive value between 0. The LVV parameter is not used. or 2. Additionally for the MLT parameter. consider a series of 5 beam elements as a single continuous member as shown below: To enable the steel design. Therefore. British Codes . called MainBeam: START GROUP DEFINITION MEMBER _MAINBEAM 11 2 38 12 3 END GROUP DEFINITION Note: This can be done in the User Interface by selecting Tools > Create New Group….2B. For example. this 5 beam member has 6 joints such that: Joint 1 = Node 3 Joint 2 = Node 1 Joint 3 = Node 33 84 — STAAD. the joint can be defined as having the upper flange restrained (positive local Y) with the a U setting or the lower flange restrained (negative local Y) with a L setting.16 Listing of Members/Elements/Joints by Specification of GROUPS). the beam needs to be defined as a group.Pro . The nodes along the beam can then be defined as the location of restraint points with J settings.Steel Design per BS5950:2000 The program can be used to calculate the values for the equivalent moment factors by defining the design member with a GROUP command (see the Technical Reference Manual section 5. 3. it has only been restrained at its ends.Joint 4 = Node 14 Joint 5 = Node 7 Joint 6 = Node 2 a.4. MY and MYX Say that this member has been restrained in its’ major axis (local Y) only at the ends. local Z axis: MY _ MainBeam J1 J3 J6 For the lateral flexural buckling. local Y axis: MX _MainBeam J1 J6 For the minor axis. Hence: For the major axis. Note that the load case specified with this parameter will not be designed as a separate load case. The following is the correct syntax for the parameter: International Design Codes Manual — 85 . (joint 5). local X axis: MYX _ MainBeam J1 J6 b. Consider MX. Hence: MLT _MainBeam J1 T3 L5 J6 To split the beam into two buckling lengths for L at joint 14: y MY _groupname J1 J4 J6 7. SWAY – Sway Loadcase This parameter is used to specify a load case that is to be treated as a sway load case in the context of clause 4. In the minor axis (local Z) it has been restrained at the ends and also at node number 33 (joint 3).3. This load case would be set up to represent the k M amp s mentioned in this clause and the steel design module would add the forces from this load case to the forces of the other load case it is designed for. Consider MLT Say that this member has been restrained at its’ ends against lateral torsional buckling and the top flange has been restrained at node number 33 (joint 3) and only the lower flange at node number 7.8. For local flexural buckling. When code checking is selected. Code checking can be done with any type of steel section listed in Section 2B. Specify whether to perform code checking or member selection along with the list of members.0 or any other specified RATIO value).). and the location (distance from the start of the member of forces in the member where the critical condition occurs).Steel Design per BS5950:2000 Parameter Name SWAY Default Value Description (load case number) ALL MEMBER (member list) _(group name) Example SWAY 5 MEM 1 TO 10 SWAY 6 _MAINBEAMS 2B. Specify design parameter values. British Codes . l l These operations may be repeated by the user any number of times depending upon the design requirements. The member design facilities provide the user with the ability to carry out a number of different design operations. The operations to perform a design are: l Specify the load cases to be considered in the design.7.2B. the program uses the start and end forces for code checking. the default is all load cases. the critical condition of BS5950 code (like any of the BS5950 specifications for compression. 2B.8 Code Checking The purpose of code checking is to ascertain whether the provided section properties of the members are adequate.3 of the Technical Reference Manual. etc. the program calculates and prints whether the members have passed or failed the checks. except profiles defined in GENERAL and ISECTION tables. if different from the default values. The adequacy is checked as per BS5950. Code checking is done using the forces and moments at specific sections of the members. the value of the ratio of the critical condition (overstressed for value more than 1.4 or any of the user defined sections as described in Section 1. tension. 86 — STAAD.Pro . shear.7 Design Operations STAAD contains a broad set of facilities for the design of structural members as individual components of an analyzed structure. the governing load case. If no sections are specified. These facilities may be used selectively in accordance with the requirements of the design problem. . TABLE refers to steel section name. the lightest section. RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition. the program produces the results in a tabulated fashion.e. Selection of members. whose properties are originally input from a user created table. will be limited to sections in the user table. If the RESULT is FAIL. Normally a value of 1. CRITICAL COND refers to the section of the BS5950 code which governs the design. The items in the output table are explained as follows: MEMBER refers to the member number for which the design is performed. Refer to Section 2. Refer to Section 5.9 Member Selection STAAD is capable of performing design operations on specified members.5 of the Technical Reference Manual for general information on Code Checking. The section selected will be of the same type section as originally designated for the member being designed. Member selection can also be constrained by the parameters DMAX and DMIN. Once an analysis has been performed.0 or less will mean the member has passed. there will be an asterisk (*) mark on front of the member. the program can select the most economical section.48. Refer to Section 5. RESULTS prints whether the member has PASSED or FAILED.6 of the Technical Reference Manual for general information on Member Selection.Note: PRISMATIC sections are also not acceptable steel sections for design per BS5950 in STAAD.10 Tabulated Results of Steel Design For code checking or member selection. 2B. 2B.Pro. International Design Codes Manual — 87 .48. Refer to Section 2. Member selection cannot be performed on members whose section properties are input as prismatic or as above limitations for code checking. which limits the maximum and minimum depth of the members.8 Code Checking.3 of the Technical Reference Manual for details the specification of the Member Selection command. Member selection can be performed with all the types of steel sections with the same limitations as defined in section 2B.2 of the Technical Reference Manual for details the specification of the Code Checking command. which has been checked against the steel code or has been selected. which fulfills the code requirements for the specified member. i. 00. moment in local Y-axis and the moment in local z-axis respectively. in most cases.66 C 0. my = 1.10.46 0.66 C 0. allowable axial capacity in compression (PC) and tension (PT) and shear capacity (PV).6 0.00.3.6 0. only FX.769 3 179.1 Example output for TRACK 0.10.00.kN. MY. myx = 1. TRACK 2.3 PC= 2455.0 will produce the design results as shown in section 2B.4 MCY= 234. LOCATION specifies the actual distance from the start of the member to the section where design forces govern.66 C 0.05 MRZ= 516.46 0. Although STAAD does consider all the member forces and moments (except torsion) to perform design. MY and MZ are printed since they are the ones which are of interest.0 PV= 600.0 MEMBER RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST UC305X305X118 PASS BS-4.3 | |---------------------------------------------------------------------| TABLE 2B.00 ======================================================================= MATERIAL DATA TABLE 88 — STAAD.3 Example output for TRACK 2.0.9 MRY= 234.00 334.0 MB= 435.00 TABLE 2B. British Codes .3.00 | | PZ= 3975.Pro .3.00 334.6 0.769 3 179.00 334.m SECTION CLASS 1 | |MCZ= 519. TRACK If the parameter TRACK is set to 1.0 MEMBER RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST UC305X305X118 PASS BS-4. and MZ provide the axial force.00 FX/PZ = 0.10.Steel Design per BS5950:2000 LOADING provides the load case number.1| | BUCKLING CO-EFFICIENTS mLT = 1.0 MEMBER RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST UC305X305X118 PASS BS-4.2B. the program will block out part of the table and will print the allowable bending capacities in compression (MCY & MCZ) and reduced moment capacities (MRY & MRZ). which governed the design FX.9 PT= 0. mx = 1.9.00 |---------------------------------------------------------------------| | CALCULATED CAPACITIES FOR MEMB 1 UNIT .2 Example output for TRACK 1. An example of each TRACK setting follows: 2B.46 0.769 3 179. 0 334.46 : My = 0.143 3 85. 2B.647 3 179. the spacing is set with the PNL parameter.00 Gross Area = 150. If the plate girder has intermediate stiffeners. see the parameter list for more information.3.3 Shear Capacity : 1645.3.000 895.4) if d/t > 70 ε for ‘rolled sections’ or d/t >62 ε for ‘welded sections’.2 0.kN. The following printout is then included if a TRACK 2.5 0.00 : myx = 1.740 DESIGN DATA (units .3.3.000 895.3 Reduced Moment Capacity : 516.00 Net Area = 127.3 .m) BS5950-1/2000 Section Class : PLASTIC Squash Load : 3975.1 0.004 9060.2.2 600.Grade of steel = S 275 Modulus of elasticity = 210 kN/mm2 Design Strength (py) = 265 N/mm2 SECTION PROPERTIES (units .46 : Mx = 334.5 0.2 .589 7.471 37. Area = 150.6 0.00 : My = 0.000 Shear Area : 103.203 Radius of gyration (cm) : 13.00 Mlt = 334.0 ANNEX I.4 234.001 Plastic modulus : 1960.00 z-z axis y-y axis Moment of inertia : 27700.000 6. The parameter SBLT should be used to identify sections as rolled or welded.4.3.00 : mx = 1.7 2455.0 Torsion and deflections have not been considered in the design.0 BS-4.000 LTB Coefficients & Associated Moments (kNm): mLT = 1.3.3-(Y) 0.11 Plate Girders Sections will be considered for the Plate Girder checks (BS 5950 Section 4.6 0.00 : my = 1.000 Elastic modulus : 1761.772 Effective Length : 6.842 3 179.m) (axis nomenclature as per design code) x-x axis y-y axis Slenderness : 44.098 1 239.kN.8.Minimum web thickness to avoid compression flange buckling’.526 589.000 LTB Moment Capacity (kNm) and LTB Length (m): 435.00 Axial force/Squash load : 0.7 BS-4.3. 6.153 77.7 85.7 334.7 (C) 0.7 334.7 334.045 z-z axis y-y axis Compression Capacity : 3551.6 BS-4.9 234.3. These are then used to check against the code clauses ‘4.cm) Member Length = 600.Minimum web thickness for serviceability’ and ‘4.1 0.m): CLAUSE RATIO LOAD FX VY VZ MZ MY BS-4.00 CRITICAL LOADS FOR EACH CLAUSE CHECK (units.4.0 output is selected: International Design Codes Manual — 89 .5 0.5 0.8.842 3 179.714 3 179.1 BUCKLING CALCULATIONS (units .769 3 85.0 BS-4.2 0.460 Effective modulus : 1960.8.50 Eff.6 334.00.9 Moment Capacity : 519.5 BS-4.kN. 2. Code checking is carried out for locations specified by the user via the SECTION command or the BEAM parameter.5 75 25 4 25 4 0 0 0 750MM_TAPER 75 2.12 Composite Sections Sections that have been defined as acting compositely with a concrete flange either from a standard database section using the CM option.2B.4. in accordance with BS 5950-1:2000.2 status = PASS : BS-4.5. The user may choose the degree of detail in the output data by setting the TRACK parameter. check. 2B. or from a modified user WIDE FLANGE database with the additional composite parameters. British Codes . Example using a Tapered I section: UNIT CM MEMBER PROPERTY 1 TO 5 TAPERED 100 2.2 .3.5 50 25 4 25 4 0 0 0 END You must specify the effective length of unrestrained compression flange using the parameter UNL. The beam is designed as other wide flange beams apart from the Lateral Torsional Buckling check which is replaced by the Annex G.4.5 75 25 4 25 4 Example using a USER table: START USER TABLE TABLE 1 UNIT CM ISECTION 1000MM_TAPER 100 2.13 Design of Tapered Beams Sections will be checked as tapered members provided that are defined either as a Tapered I section or from a USER table.3 status = PASS The section is then checked for shear buckling resistance using clause ‘4.3.Steel Design per BS5950:2000 Shear Buckling check is required: Vb = 1070 kN : qw = 118 N/mm2 d = 900 mm : t = 10 mm : a = 200 mm : pyf = 275 N/mm2 BS-4. 2B.2. cannot be designed with BS5950:2000.Pro . The program compares the resistance of members with the applied load effects. The results are presented in a form of a PASS/FAIL identifier and a RATIO of load effect to resistance for each member checked.Simplified method’ and the result is included in the ratio checks.4. 90 — STAAD. see G. ..2 Check Moment for Taper Members as per clause G.13.2. M is the moment about the major axis acting at the point i considered. xi P is the compression resistance from 4. 2B.13.2B.3.2.5 λ = Ly /ry Where: a is the distance between the reference axis and the axis of restraint. s L is the length of the segment. c M is the buckling resistance moment M from 4.13.Fc/Pc) Where: F is the longitudinal compression at the check location.7.4 for a slenderness λ . h is the distance between the shear centers of the flanges. UB or UC). except that the following is used in place of clause 4.2.2.4.3. Z or Z of TB eff eff the cross-section at the point i considered.3 Slenderness lTC λTC = yλ Where: 2 1 + (2a / h s) y= 2 2 1 + 2 a / h + 0. y x is the torsional index International Design Codes Manual — 91 .g.2.1 Design Equations A beam defined with tapered properties as defined above will be checked as a regular wide flange (e. based on the appropriate modulus S.3.2 The following criterion is checked at each defined check position in the length of the member defined by the BEAM parameter.05( λ / x ) ( ) s 0. see G.6. Mxi ≤ Mbi (1 .6 for an equivalent bi b slenderness λ .3 G. c TC y based on the properties of the minimum depth of cross-section within the segment length L 2B. y r is the radius of gyration for buckling about the minor axis. the lateral torsional buckling check. S . the taper factor. British Codes . x is the torsional index of the minimum depth cross-section.4 G. see G. see 4.Pro . c. is as follows: c = 1+ 3 D max x − 9 D m in 2/3 − 1 Where: D is the maximum depth of cross-section within the length Ly. see Figure max G. for a two-flange haunch: 4a / h s vt = 2 2 1 + 2 a / h + 0.13.3.2. see Figure min G.4.2B and x ≥ 20. 2B.6.2B.5.3.3.0 (unity).5 Where: C is the taper factor.8 Otherwise.2.05( λ / x ) s) ( 0.13.Steel Design per BS5950:2000 2B. D is the minimum depth of cross-section within the length Ly. c is taken as 1.5 Taper factor For an I-section with D ≥ 1.2.2 Equivalent slenderness ITB for tapered members λTB = cntνtλ Where.5 G. 92 — STAAD. Pro is capable of performing steel design based on the British code BS 5400:Part 3:1982 Steel. The implementation of part 3. Once the allowable compressive stress is determined then the moment capacity appropriate to the section type can be calculated.4 Moment Capacity Lateral torsional buckling may occur if a member has unrestrained elements in compression.3. International Design Codes Manual — 93 . the full plastic moment capacity can be attained. the design process will terminate with reference to the clause. The code is in ten parts covering various aspects of bridge design. section types are determined as per clause 9. The code deals with this effect by limiting the compressive stress to a value depending on the slenderness parameter which is a modified form of the ratio Le/Ry. Le is the effective length governed by the provision of lateral restraints satisfying the requirements of clause 9. The program then proceeds to calculate the allowable compressive stress based on appendix G7 from which the moment capacity is then determined.2C. In the case of noncompact sections. the code sets limits to the ratio as per clause 9. for the composite stage. In the case of compact sections. local buckling of elements may occur prior to reaching the full moment capacity and for this reason the extreme fibre stresses are limited to first yield. In the event of exceeding these limits. in STAAD is restricted in its scope to simply supported spans.12. In order to prevent this. concrete. assuming full restraint throughout. Design of members per BS 5400:Part 3:1982 requires the STAAD British Specialized Design Codes SELECT Code Pack. defaulting to the length of the member during construction stage and as zero.3. 2C. British Codes . Code of practice for design of steel bridges and Amd No. The following sections describe in more detail features of the design process currently available in STAAD.7 and the checks that follow will relate to the type of section considered. and composite construction.Design per BS5400 STAAD.2 Shape Limitations The capacity of sections could be limited by local buckling if the ratio of flange outstand to thickness is large. 2C. 4051 and Amd No. It is assumed that the depth remains constant and both construction and composite stages of steel I-Sections can be checked. It does not come as standard with British versions.2.3 Section Class Sections are further defined as compact or noncompact. concrete and composite bridges Part 3. Code of practice for design of steel bridges. STAAD takes the effective length as that provided by the user. In STAAD.1 General Comments The British Standard. 2C. BS5400 adopts the limit state design philosophy and is applicable to steel. 2C.1. 6488. 1 and Cl.8. British Codes .Pro . its value stays at that specified number until it is specified again. as outlined in clause is a function of the limiting shear strength. in current units of length. 0. you can determine the stage under consideration.2. Usually this is major axis.6 Design Parameters Available design parameters to be used in conjunction with BS5400 are listed in table 2C. in current units of length.3. Table 2C. Length to calculate slenderness ratio for bending about Y-axis. When specifying composite properties the first parameter is assigned a negative value and four additional parameters provided giving details of the concrete section.3. member properties should be changed to composite and the WET parameter set to 2. Usually this is minor axis. 1.9. Rolled sections.5 Shear Capacity The shear capacity.8.19 of the manual for specification of user tables).1-BS5400 Design Parameters Parameter Name ESTIFF Default Value 0 Description Specify the criteria used for the design of compression members with moments. Member passes if either Cl. KZ 1. 2C. 4. This is the way STAAD works for all codes.2C. which is dependant on the slenderness ratio. taking into consideration the construction stage.8.1.3.1 or Cl.2 check. Length to calculate slenderness ratio for bending about Z-axis. Note: Once a parameter is specified. 4. 4. In the second. Member passes if both Cl.0. K value for bending about Z-axis. The shear capacity is then calculated based on the formula given under clause 9. STAAD follows the iterative procedure of appendix G8 to determine the limiting shear strength of the web panel. composite or non-composite.3.0 K value for bending about Y-axis.3.Design per BS5400 2C. l.2 check. See user table examples provided.3. two separate analyses are required. Depending on the value assigned to the WET parameter. In the first.8. Member properties for composite or noncomposite sections should be specified from user provided tables (refer to section 5.0 LY Member Length Member Length LZ 94 — STAAD. 4.3. KY 1. come under WIDE FLANGE section-type and built-up sections under ISECTION. member properties are non-composite and the WET parameter is set to 1.2.3.0 . For a composite design check. 0. Steel 0.0 = Rolled Section 1.0 Steel Grade per BS4360 0.0 = Built up Section SGR 0.0 Grade of concrete: 1.0 Used to control the level of detail in the output 0. Used to specify the stage of construction. 30 N/mm2 2. 50 N/mm2 Description NSF PY 1.Parameter Name MAIN Default Value 1. Print all member capacities UNL Member Length Unsupported length for calculating allowable compressive bending stress. Suppress all member capacities 1. in current units of length. Composite stage only WET 0. Grade 43 1. Composite and wet stage combined 3.0 International Design Codes Manual — 95 . Set according to Design Strength of steel SGR RATIO SBLT 1 0. Wet stage with no data saved for composite stage 1. Wet stage with data saved for composite stage 2. Yield stress of steel. Grade 55 TRACK 1.0 * Net section factor for tension members.0 Permissible ratio of actual to allowable stresses. 40 N/mm2 3. Grade 50 2. 3 Example UNIT CM WIDE FLANGE C45752 -66. 2C.7.66 42.76 15.1 Wide Flange Composite Using the standard definition of I sections in WIDE FLANGE.2C. 4 additional values can now be provided. This is purely for analysis and for obtaining the right section properties. 2C.15 92. It uses the American requirement of 18 times depth (CT) as the effective depth. The above values are accepted in the program by adding a '-' at the first position on the first line of data. The last is the modular ratio. For more control with British sections two new options are available in user provided tables.2 I Section The same is true for ISECTION definition in user table.5 44.05 3.66 197.223 150 150 30 10 ISECTION PG9144 -92.185 33.7 Composite Sections The definition of composite sections has been provided for in the standard sections definition (refer to Section 5.7. The program now awaits four extra values on line 2 as described above. British Codes .98 . 96 — STAAD.20.7. Please note however that composite design is not available in this portion of STAAD.9 1730 40 40 12 1 The larger British sections have been coded as USER TABLES under wide flange and are available on request to any existing user. 2C. The third is the concrete depth (d1) to be considered. If (-) is provided on the second line the program requires another 2 breadths + 1 thickness for the bottom plate.Design per BS5400 2C.Pro .1 of the Technical Reference Manual for details). The second is the concrete width to the right (b2). The first is the width of concrete to the left of center of the steel web (b1).3 34.05 2.9 153.09 21345 645 21.05 42.05 3.24 1. Thermal crack widths Finally thermal. It is recommended that the design of the structure is carried out according to BS8110. Ultimate Limit States The program is structured so that ultimate design is first carried out in accordance with recommendations given in BS8110. Smax and crack widths are calculated for the critical reinforcements and printed under each bar size. and 200 mm. the layout providing the closest area of steel is printed under each bar size. 12.125. Surface zone depths are determined based on the type of slab and critical areas of reinforcements are calculated and printed in a tabulated form.Design per BS8007 STAAD. Serviceability Limit States In the second stage. Longitudinal and transverse moments together with critical load cases for both hogging and sagging moments are also printed. the user is able to provide information on the type of slab.Concrete Design per BS8110" on page 51 2D.2D. 16. Minimum reinforcement is in any case checked and provided in each direction. 1. temperature range and crack width limits. The first and every other occurring design load case is considered as a serviceability load case and crack widths are calculated based on bar sizes and spacings proposed at the ultimate limit state check. All active design load cases are considered in turn and a tabulated output is printed showing possible reinforcement arrangements. Design of members per BS8007:1987 requires the STAAD British Specialized Design Codes SELECT Code Pack. Within these spacings.175. Crack widths due to longitudinal and transverse moments are calculated directly under bars.150. and 20 mm bars are considered with possible spacings from 100. flexural crack widths under serviceability load cases are calculated. max crack spacing.Pro is capable of performing concrete design based on the British code BS8007:1987 Design of concrete structures for retaining aqueous liquids. 2.1 Design Process The design process is carried out in three stages. midway between and at corners. Through available parameters. crack width calculations are carried out. See "British Codes . 3. British Codes . The information in this section is to be used in conjunction with the BS8110. Four bar sizes are considered and for each. International Design Codes Manual — 97 . A tabulated output indicating critical serviceability load cases and moments for top and bottom of the slab is then produced. It does not come as standard with British versions. unless modified by the recommendations given in BS8007. Wood & Armer moments may also be included in the design. This is considered the same on both surfaces. A* is any angle in degrees. Table 2D. in current units of length.2 Design Parameters The program contains a number of parameters which are needed to perform and control the design to BS8007. ground or suspended as defined in BS8007 1 = Suspended Slab 2 = Ground Slab TEMP 30°C Temperature range to be considered in thermal crack width calculations Limiting thermal crack width. Note: Once a parameter is specified.Design per BS8007 Maximum bar spacing to limit crack widths to the user's limit is also printed under each bar size. in current units of length. Table 2D. A* Skew angle considered in Wood & Armer equations.1 contains a complete list of available parameters with their default values. This is the way STAAD works for all codes.slabs on 500. Default values of commonly used values for conventional design practice have been chosen as the basis. Distance from the outer surface to the edge of the bar. 2D. CLEAR SRA 0.1-BS8007 Design Parameters Parameter Default Name Value FC 30 N/mm 2 20 mm Description Concrete grade. Orthogonal reinforcement layout without considering torsional moment Mxy .2 mm * Provided in current unit systems 98 — STAAD.2D.Pro .0 SCON 1 Parameter which indicates the type of slab ee. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. British Codes . its value stays at that specified number until it is specified again. in current units of length and force. CRACK * 0. orthogonal reinforcement layout with Mxy used to calculate Wood & Armer moments for design. The SRA parameter (Set Reinforcement Angle) can be manipulated to introduce Wood & Armer moments into the design replacing the pure Mx.2D. measured between the local element x axis anti-clockwise (positive).3 Structural Model Structural slabs that are to be designed to BS8007 must be modeled using finite elements. UNIT MM ELEMENT PROPERTIES 1 TO 10 THI 300. an angle is given in degrees. from the center of the container.4 Wood & Armer Moments This is controlled by the SRA parameter.6 of the Technical Reference Manual for information on the sign convention used in the program for defining elements It is recommended to connect elements in such a way that the positive local z axis points outwards away. Orthogonal or skew reinforcement may be considered. An example of a rectangular tank is provided to demonstrate the above procedure. If the default value of zero is used. If however a skew is to be considered. Refer to Section 1. Element properties are based on the thickness given under ELEMENT PROPERTIES command. SRA set to -500 will assume an orthogonal layout.0 2D. The following example demonstrates the required input for a 300 mm slab modeled with ten elements. These new design moments allow the Mxy moment to be considered when designing the section. In this manner the "Top" of elements will consistently fall on the outer surface and internal pressure loads will act in the positive direction of the local z axis. International Design Codes Manual — 99 . The resulting Mx* and My* moments are calculated and shown in the design format. the design will be based on the Mx and My moments which are the direct results of STAAD analysis. My moments. 100 — STAAD.Pro . British Codes . Both unreduced and effective section properties are used in the design stage.Design per British Cold Formed Steel Code STAAD. Code checking is carried out for locations specified by the user via the SECTION command or the BEAM parameter. (Design of Structures using Cold Formed Steel Sections). The Tables are currently available for the following shapes: l Channel with Lips Channel without Lips Z with Lips Pipe Tube l l l l Shape assignment may be done using the General | Property page of the graphical user interface (GUI) or by specifying the section designation symbol in the input file.1 Code Checking The program compares the resistance of members with the applied load effects. in accordance with BS 5950-5:1998.Pro is capable of performing steel design based on the British code BS 5950-5:1998 Structural use of steelwork in building . shear. Design of members per BS 5950-1:2000 requires the STAAD British Std Design Codes SELECT Code Pack.2. The results are presented in a form of a PASS/FAIL identifier and a RATIO of load effect to resistance for each member checked. International Design Codes Manual — 101 .Part 5: Code of practice for design of cold formed thin gauge sections . as well as their combinations.1 Cross-Sectional Properties The user specifies the geometry of the cross-section by selecting one of the section shape designations from the Gross Section Property Tables published in the “The Steel Construction Institute”. STAAD. 2E. compression.2 Design Procedure The following two design modes are available: 2E. 2E. The properties listed in the tables are gross section properties. The program allows design of single (non-composite) members in tension. as applicable. bending. The user may choose the degree of detail in the output data by setting the TRACK parameter.Pro uses unreduced section properties in the structure analysis stage.2E. Cold work of forming strengthening effects have been included as an option. Cross-sectional properties and overall slenderness of members are checked for compliance with: l Clause 6. section 7 is described below. the program leaves the member unchanged.2 of the Technical Reference Manual for details the specification of the Code Checking command.2 Combined bending and tension As per clause 7. In addition.1 Tensile Strength The allowable tensile strength. angle.Design per British Cold Formed Steel Code Refer to Section 2.2 Member Selection The user may request that the program search the cold formed steel shapes database (BS standard sections) for alternative members that pass the code check and meet the least weight criterion. The program will then evaluate all database sections of the type initially specified (i.2. if a suitable replacement is found.5.3. a minimum and/or maximum acceptable depth of the member may be specified.48.1 t Pt = Aepy Where: A is the net area An determined in accordance with cl.3 of the Technical Reference Manual for details the specification of the Member Selection command. P of the member should be determined from clause 7.2E. The tensile strength. as calculated in STAAD as per BS5950-5. channel. Refer to Section 5. presents design results for that section. Refer to Section 2.Pro . The program calculates effective section properties in accordance with Section 4 of the subject code.5 of the Technical Reference Manual for general information on Code Checking.6 of the Technical Reference Manual for general information on Member Selection.4 e p is the design strength y 2E. regardless of whether it passes the code check or not. 2E.. Maximum Flat Width Ratios for Elements in Compression l 2E.3 of BS 5950-5:1998 members subjected to both axial tension and bending should be proportioned such that the following relationships are satisfied at the ultimate limit state Ft/Pt + Mz/Mcz + My /Mcy ≤ 1 102 — STAAD.2.3.e. etc.) and. If no section satisfying the depth restrictions or lighter than the initial one can be found. British Codes .3 Design Equations 2E.2.2.2.3. Refer to Section 5. Maximum Effective Slenderness Ratio for members in Compression Clause 4.48. M . otherwise Where the meanings of the symbols used are indicated in the subject clause. International Design Codes Manual — 103 .1 of the subject t code M .3.M .4.3 Compressive Strength The allowable Compressive strength. Pc. 2E.Mz/Mcz ≤ 1 and My /Mcy ≤ 1 Where F is the applies tensile strength t P is the tensile capacity determined in accordance with clause 7. the buckling resistance under axial load.M z y cz cy are as defined in clause 6. section 6 is described below For sections symmetrical about both principal axes or closed cross-sections which are not subjected to torsional flexural buckling.3. c Where: α = (PE/PTF) when PE > PTF α = 1.2 using factored slenderness ratio αLE/r in place of actual slenderness ratio while reading Table 10 for the value of Compressive strength(p ).3.2.2.3 of the subject code Pc = PEPcs ϕ + ϕ 2 − PEPcs For Sections symmetrical about a single axis and which are not subject to torsional flexural buckling. and which are subject to torsional flexural buckling should be done according to the stipulations of the clause 6.4 of the subject code P ′c = M c Pc (M c +Pc e s) Where the meanings of the symbols used are indicated in the subject clauses. as calculated in STAAD as per BS5950-5.2 of the subject code 2E. may be obtained from the following equation as per clause 6.4 Torsional flexural buckling Design of the members which have at least one axis of symmetry.2. may be obtained from the following equation as per clause 6. Pc. the buckling resistance under axial load. 3. 2E. M .6 in the manner described cz cy b herein below.2.Design per British Cold Formed Steel Code 2E.is the lateral buckling resistance moment as per clause 5.3.2.2 b P is the flexural buckling load in compression for bending about the local Z Ez axis P is the flexural buckling load in compression for bending about the local Y Ey axis C .7 Calculation of moment capacities For restrained beams. the applied moment based on factored loads should not be greater then 104 — STAAD.3 of the subject code For Beams not subjected to lateral buckling.2.6 Overall buckling check as per clause 6.4.as per clause 5. as per clause 5.C bz by are taken as unity unless their values are specified by the user M . the following relationship should be satisfied Fc Pc My F C by M cy 1 − c P Ey + Mz F C bx M cz1 − c P Ez + ≤1 For Beams subjected to lateral buckling. the following relationship should be satisfied Fc Pc + Mz Mb + My F C by M cy 1 − c P Ey ≤1 F is the applied axial load c P is the short strut capacity as per clause 6.2 and 5.2.2 and 5.4.2 of the subject code Fc/Pcs + Mz/Mcz + My /Mcy ≤ 1 2E.2E.5 Combined bending and compression Members subjected to both axial compression and bending should be checked for local capacity and overall buckling Local capacity check as per clause 6. in the absence of cy F and M .6. British Codes .Pro .3. and M are calculated from clause numbers 5.6 c y M is the moment capacity in bending about the local Y axis.3 cs z M is the applied bending moment about z axis M is the applied bending moment about y axis y M is the moment capacity in bending about the local Z axis in the absence of cz F and M .6 c z M.2 and 5. 13 − 0. 2E. qcr) Where: International Design Codes Manual — 105 .3 of the subject code. p or the shear v buckling strength.4.the bending moment resistance of the section.3.4. M may be calculated as follows b. cr The parameters are calculated as follows : pv = 0.2.2.2 E η is the Perry coefficient Please refer clause numbers 5.7 ´ p as per clause 5. product of design strength p and elastic Y y modules of the gross section with respect to the compression flange Zc M is the elastic lateral buckling resistance as per clause 5.8 Shear Strength The maximum shear stress should not be greater then 0. M Mcz = Szz x po Mcy = Syy x po D po = 1.0019 w t Ys 280 c p y Where M is the Moment resistance of the section in z axis cz cz M is the Moment resistance of the section in z axis p is the limiting stress for bending elements under stress gradient and should o not greater then design strength p y For unrestrained beams the applied moment based on factored loads should not be greater than the smaller of the bending moment resistance of the section . M b Then buckling resistance moment. q as stipulated in clause 5. Mb = M EM y 2 ϕB + ϕB − M EM y ≤ Mc φB = [My + (1 + η)ME]/2 M is the yield moment of the section . M .2 y The average shear stress should not exceed the lesser of the shear yield strength.6·py qcr = (1000·t/D)2 N/mm2 Pv = A·min(pv .6.2 and 5. and the buckling c resistance moment of the beam.6 of the subject code for a detailed discussion regarding the parameters used in the abovementioned equations. This is the way STAAD works for all codes.48. its value stays at that specified number until it is specified again.1 are used to control the design procedure.3. Note: Once a parameter is specified. Table 2E.Pro . These parameters communicate design decisions from the engineer to the program and thus allow the engineer to control the design process to suit an application's specific needs. 106 — STAAD.4 Design Parameters The design parameters outlined in Table 2E. The default parameter values have been selected such that they are frequently used numbers for conventional design.1 of the Technical Reference Manual. British Codes .2 2E. Depending on the particular design requirements. See section 5.5.9 Combined bending and Shear For beam webs subjected to both bending and shear stresses the member should be designed to satisfy the following relationship as per the stipulations of clause 5.2.2 of the subject code (Fv /Pv )2 + (M/Mc)2 ≤ 1 Where: F is the shear force v M is the bending moment acting at the same section as F c v M is the moment capacity determined in accordance with 5.Design per British Cold Formed Steel Code P is the shear capacity in N/mm 2 v p is the design strength in N/mm 2 y t is the web thickness in mm D is the web depth in mm 2E. some or all of these parameter values may be changed to exactly model the physical structure.2E.1-British Cold Formed Steel Design Parameters Parameter Name CODE Default Value BS5950 COLD Description Design Code to follow. 0.6.5. and instead. See BS:5950-5:1998. See b BS:5950-5:1998. See b BS:5950-5:1998.0 CWY 1.0 International Design Codes Manual — 107 .0 (default).4 0 – effect should not be included 1 – effect should be included CMZ 1. Specifies whether the cold work of forming strengthening effect should be included in resistance computation. If the BEAM value is 0. For TRUSS members only start and end locations are designed.5.6.0 CMY 1. the adequacy of the member is determined by checking a total of 13 equally spaced locations along the length of the member. checking is done only at the locations specified by the SECTION command (See STAAD manual for details. Coefficient of equivalent uniform bending C . Coefficient of equivalent uniform bending C . Used for Combined axial load and bending design.0 Description When this parameter is set to 1. Used for Combined axial load and bending design. the 13 location check is not conducted.3.Parameter Name BEAM Default Value 1. 6 Values: 0 – Section subject to torsional flexural buckling 1 – Section not subject to torsional flexural buckling FU 430 MPa Ultimate tensile strength of steel in current units. Effective length factor for torsional buckling. British Codes . FYLD 250 MPa KX 1. 5.Design per British Cold Formed Steel Code Parameter Name FLX Default Value 1 Description Specifies whether torsional-flexural buckling restraint is provided or is not necessary for the member.Pro . Values can range from 0.0 108 — STAAD. See BS:59505:1998. It is a fraction and is unit-less. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression. Yield strength of steel in current units.01 (for a column completely prevented from buckling) to any user specified large value.2E. It is used to compute the KL/R ratio for determining the capacity in axial compression.0 LX Member length International Design Codes Manual — 109 . It is a fraction and is unit-less. Values can range from 0. It is used to compute the KL/R ratio for determining the capacity in axial compression. Values can range from 0.01 (for a column completely prevented from buckling) to any user specified large value. Unbraced length for twisting. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression. Effective length factor for overall buckling in the local Z-axis.0 Description Effective length factor for overall buckling about the local Y-axis.01 (for a member completely prevented from buckling) to any user specified large value. It is input in the current units of length.Parameter Name KY Default Value 1. KZ 1. Values can range from 0.01 (for a member completely prevented from torsional buckling) to any user specified large value. It is a fraction and is unit-less. Design per British Cold Formed Steel Code Parameter Name LY Default Value Member length Description Effective length for overall buckling in the local Yaxis. It is used to compute the KL/R ratio for determining the capacity in axial compression. It is input in the current units of length. British Codes . Effective length for overall buckling in the local Zaxis. Values can range from 0. Values can range from 0.Pro . LZ Member length 110 — STAAD. It is input in the current units of length.01 (for a member completely prevented from buckling) to any user specified large value.01 (for a member completely prevented from buckling) to any user specified large value.2E. It is used to compute the KL/R ratio for determining the capacity in axial compression. 0 Net section factor for tension members Maximum allowable depth. RATIO 1. It is input in the current units of length.2: 0 – Do not check slenderness ratio 1 – Check members resisting normal loads (180) 2 .Check members resisting reversal of stress (350) NSF 1. Permissible ratio of actual to allowable stresses DMAX 2540.Parameter Name MAIN Default Value 0 Description Specify the design for slenderness against the maximum slenderness as per Clause 6.2.0 cm.0 International Design Codes Manual — 111 .Check members resisting selfweight and wind loads (250) 3 . These members have been designed as per BS 5950 Part 5. The allowable values are: 0 . we have assigned Channel sections with lips to different members.Design per British Cold Formed Steel Code Parameter Name TRACK Default Value 0 Description This parameter is used to control the level of detail in which the design output is reported in the output file. 7 TO 14 have been assigned the section 170CLHS56X18.Prints member and material properties in addition to that printed by TRACK 2. 2.5 Verification Problem Shown below is a verification example for reference purposes.2E. and PASS/FAIL status.Pro . Member numbers 28 to 31 have been assigned section 230CLHS66X16. 2E.member numbers 3 TO 6 and 15 TO 19 have been assigned the section 230CLMIL70X30 and member numbers 1. ratio. British Codes . 1 . section name.Prints the design summary in addition to that printed by TRACK 1 2 . 112 — STAAD.Prints only the member number. In this problem. Other sections have been assigned from the AISI shapes database (American cold-formed steel) and designed in accordance with that code. Bending Check As per Clause 5.46 X106 = 0.19 X106 = 0.1 Solution A. for stiffened webs is given by the minimum of o D po = 1. p .4(332.6.3 / 3.2 of BS 5950 –Part 5 the limiting compressive stress.727 N/mm2 The limiting compressive moments in local Y and Z axes will be given by Mcz = Szz·po = 27. the buckling resistance moment Mb = M EM y 2 ϕB + ϕB − M EM y ≤ Mc Where: The Yield moment of section is given by MY = Szz · po = 9.13 .2 is calculated to be ME = 4.755 N·m at node 7 Bending Ratio Z = 2.84·FU) = 361.50) = 3.2E.0.19(10)6 + (1 + 0.2.649(10)6 ]/2 = 2.6.0057 Biaxial Bending ratio = 0.2 N/mm2 So that p0 = [1.0)4.0057 = 0.15 X106 / 9. where Py = Min ( FYLD.325(10)10 International Design Codes Manual — 113 .727) = 9.2.235 + 0. 0.4(5.632.19(10)6 N·mm The elastic buckling resistance moment as per clause 5.632.2.46(10)6 N·mm Maximum bending moment about local Z = 2159 N·m at node 7 Maximum bending moment about local Y = 19.427.2.13 − 0.8)·(279.649(10)6 N·mm And φB = [My + (1 + η)ME]/2 So that φB = [9.19(10)6 N·mm Mcy = Syy ·po = 27.0019 w t Ys 280 p y p0 = Py.235 Bending Ratio Y = 19755.2 = 332.212/280)1/2 ]·361.0019·(170/1.5.2407 Buckling resistance moment M b As per section 5. 19(10) 2 6 6 = 9. 782N For Channel section (being singly symmetric).448 N Perry Coefficient (η) = 0. M . 782 38. British Codes .649(10) ⋅ 9.02074 φ = [Pcs + (1 + η)PE]/2 = 683.698(344) = 157.4 is P ′c = M c Pc (M c +Pc e s) Where: The limiting compressive moment. of the geometric neutral axis of the gross cross section and that of s the effective cross section is equal to 38.as calculated above And the distance. 782 9.325(10) 10 + 2.185(10)6 N E The short strut capacity (Pcs ) is given by Aeff·py = 457.4. P ′c = 9.436.46(10)6(1 .7N Compression ratio = 3.7 = 0.436. Axial Compression and Bending Fc Pc + Mz Mb + My F C by M cy 1 − c P Ey ≤1 3.19(10) ⋅ 153. e .325(10) 10 − 4.185(10)6 )] = 0.7 + 2.75/1.15(10)6/(9.436.3/[1.755.788.19(10)6 B.2 114 — STAAD.45 N Buckling resistance Pc = PEPcs ϕ + ϕ 2 − PEPcs = 153.75/93.2.0366 C. in the relevant direction is equal to 9.0 * 3.512.436.2E.19(10)6 c N·mm.Design per British Cold Formed Steel Code Which yields Mb = 4. 788.98(10)6 ) + 19.2578 Local capacity check as per clause 6.19(10) + 153.98(10)6N ⋅ mm 2.3.649(10)6 ⋅ 9. Compression Check The Axial force induced in member# 1 is 3.75/93.788.24 m So that. Buckling Resistance as per clause 6.75 N The elastic flexural buckling load P = 1.24 6 6 ( ) = 93.Pro . 2773 D.15·106 /(9.6 N Shear Ratio Y = 5.8/170)2 = 112.1675 Shear Ratio Z = 5.3 Fc Pc + Mz F C bx M cz1 − c P Ez + My F C by M cy 1 − c P Ey ≤1 = 0.19·106 )]2 = 0.579.0057 0.2773 none 0.212) + 2.72/33.6 = 0. 436.278 0.11 N/mm2 Pv = A·min(pv .52 N/mm2 qcr = (1000·t/D)2 = (1000·1.4)2 + [2.2 Shear with bending on Z (Fv /Pv )2 + (Mz/Mcz)2 = (5.037 Hand Difference Calculation 0.81(10) 6 = 0.08327 Shear with bending on Y (Fv /Pv )2 + (My /Mcy )2 = (67.75 457.148.2647 Overall buckling check per 6. 755.148.2 Comparison Table 2E.627.0031 E.Fc Pcs + Mz M cz + My M cy = 3.4 = 0. Shear Check with Bending as per clause 5.755.6·py = 0.19(10) 6 + 19.5.579.3 1.Pro Result 0.698(379.4.627.4 N Shear resistance Z = 21.15(10)6 9.46·106 )]2 = 0.148.4.72/21.6)2 + [19.3 pv = 0.006 0. Shear Check as per clause 5.212) = 227.6(379.2 and 5.72/33.000043 2E.241 none none none International Design Codes Manual — 115 .579.0366 none 0.2407 0.236 0.4.627.3/(3.114/21.5. qcr) Shear resistance Y = 33.2-Comparison for verification problem Criteria Axial compression ratio Axial compression and bending interaction ratio (overall buckling) Bending Z ratio Bending Y ratio Biaxial bending ratio STAAD.235 0. 0031 0. 19 10 0 0.000 0.Pro . 34 4 19. 4 10 5 10. 2 0 5 10. British Codes . 17 5 5 6. 25 17 13. 32 1 21. 9 9 10. 24 9 17. 31 4 20. 15 5 5 2. 6 5 5 10. 20 10 0 10.Design per British Cold Formed Steel Code Criteria Shear Z ratio Shear Y ratio Bending Z and Shear Y interaction ratio Bending Y and Shear Z interaction ratio STAAD. 7 0 5 2. 10 10 2. 13 13 14. 8 8 9. 4 2 6. 30 3 19. 21 15 11.1675 0. 20 7 15. 13 10 5 6. 37 20 3. 21 0 0 10.2E. 14 10 5 8. 36 2 20. 12 12 13. 3 1 5. 17 16 17. 12 10 5 4.3 Input File STAAD SPACE SET ECHO OFF INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES 1 0 5 0. 2 3 11. 23 16 12. 5 5 5 0. 38 3 22. MEMBER INCIDENCES 1 1 7. 11 11 12. 14 14 4. 18 5 5 8. 22 8 16. 35 19 1. 5 5 3. 18 17 18. 19 18 6.Pro Result 0. MEMBER PROPERTY COLDFORMED AMERICAN 32 TO 39 TABLE ST 3LU3X060 20 TO 27 TABLE ST 3HU3X075 MEMBER PROPERTY COLDFORMED BRITISH 28 TO 31 TABLE ST 230CLHS66X16 3 TO 6 15 TO 19 TABLE ST 230CLMIL70X30 1 2 7 TO 14 TABLE ST 170CLHS56X18 UNIT MMS PRINT MEMBER PROPERTIES LIST 32 20 28 3 1 116 — STAAD. 22 0 0 0.168 0.08327 none none none 0. 15 5 15. 8 0 5 4.003 0. 33 21 4. 11 10 5 2. 28 1 22. 39 22 2. 29 2 21. 6 6 4. 16 5 5 4.000043 none 2E. 7 7 8. 10 0 5 8. 16 15 16.084 Hand Difference Calculation 0. 27 18 14. 3 10 5 0. 26 10 18. 9 0 5 6.5. 3 0 5 JOINT LOAD 1 2 FX 0.6 PERFORM ANALYSIS PRINT STATICS CHECK UNIT KGS CM PRINT JOINT DISP LIST 1 4 16 PRINT SUPPORT REACTIONS PRINT MEMBER FORCES LIST 3 24 28 UNIT KIP INCH PARAMETER 1 CODE AISI FYLD 55 ALL CWY 1 ALL BEAM 1 ALL TRACK 2 ALL CHECK CODE MEMB 20 21 PARAMETER 2 CODE BS5950 COLD TRACK 2 MEMB 1 TO 19 28 TO 31 CHECK CODE MEMB 1 2 International Design Codes Manual — 117 .489024 ALPHA 6.176E+006 POISSON 0.6 2 4 FZ -0.3 DENSITY 0.03 END DEFINE MATERIAL CONSTANTS BETA 90 MEMB 20 TO 27 MATERIAL STEEL MEMB 1 TO 39 MEMBER TENSION 32 TO 39 UNIT FEET KIP LOAD 1 VERTICAL AND HORIZONTAL MEMBER LOAD 3 TO 6 20 TO 27 UNI GY -0.5E-006 DAMP 0.SUPPORTS 19 TO 22 PINNED UNIT FEET DEFINE MATERIAL START ISOTROPIC STEEL E 4. Pro .Pro CODE CHECKING . 118 — STAAD.Y Ratio 0.241 BS-5.1) *********************** UNITS : MM.4 Output The excerpts from the design output for member number 1 are as follows: STAAD.70 Moment Capacity (Mc) : 9.47 33.Z Ratio 0.58 RATIO 0.42 27.Axial BS-6.003 BS-5.17 Shear Capacity (Pv) : 21.5.60 LOCATION: 609.006 BS-5.5.00 N/mm2 170CLHS56X18 60.45 Net Area (Ae): z-z axis y-y axis 237.2 Bending -Y & Shear .5.037 0.Z 0.000 Torsion and deflections have not been considered in the design.278 GOV. KNM.1 Bending Ratio .2 Bending -Z & Shear .93 235.1 Biaxial Bending Ratio 0.Y y-y axis 3.cm) Section Name : Member Length : Gross Area(Ag) : Moment of inertia (I) Moment of inertia (Ie) Elastic modulus (Zet) Elastic modulus (Zec) DESIGN DATA: z-z axis Compression Capacity (Pc) : 93.4 Shear Ratio .1 Bending Ratio .Z BS-5.Design per British Cold Formed Steel Code FINISH 2E.00 LTB Capacity (Mb) : 9.084 BS-5.42 4.21 N/mm2 430.236 0.4-Bend + Compress GOV. British Codes .27 21. KN.85 5.Y 0.4 Bend-Compression ratio BS-5. MPA -----------------------------------------------------------------------------| MEMBER# 1 SECTION: 170CLHS56X18 LEN: 609.MODE: 6.4 Shear Ratio .96 5.17 EACH CLAUSE CHECK UNDER CRITICAL LOAD : CLAUSE COMBINATION BS-6.60 | | STATUS: PASS RATIO = 0.168 BS-5.20 27.3 Compression ratio .LOAD: 1 | |----------------------------------------------------------------------------| MATERIAL DATA: Yield strength of steel : Ultimate tensile strength : SECTION PROPERTIES:(units .2E.(BS5950-5-v1.46 19.50 : : : : 379.55 10.278 0. Section 3 Canadian Codes International Design Codes Manual — 119 . Pro .120 — STAAD. Prismatic (Rectangular.3 1994 Design of Concrete Structures. ZD 300. STAAD accounts for the secondary moments. Square and Circular) For Slabs . l l l For Beams . due to axial loads and deflections.Pro is capable of performing concrete design based on the Candadian code CSA A23. Design of members per CSA A23. In the above input.3-94 Clause 10.Prismatic (Rectangular. the first set of members are rectangular (450mm depth and 300mm width) and the second set of members. will be assumed to be circular with a 300mm diameter 3A. 11 14 PR YD 300.1 Section Types for Concrete Design The following types of cross sections for concrete members can be designed. Canadian Codes .13. After solving for the joint displacements of the structure. Refer to Section 5.37.2 of the Technical Reference Manual for additional details on this analysis facility. International Design Codes Manual — 121 .2 Member Dimensions Concrete members that are to be designed by STAAD must have certain section properties input under the MEMBER PROPERTIES command.4-noded Plate Elements 3A. the program calculates the additional moments induced in the structure due to the P-Delta effect. The following example demonstrates the required input: UNIT MM MEMBER PROPERTIES 1 3 TO 7 9 PRISM YD 450.Concrete Design per CSA Standard A23. with only depth and no width provided. Therefore.3 Slenderness Effects and Analysis Considerations STAAD provides the user with two methods of accounting for the slenderness effect in the analysis and design of concrete members.3 1994 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack. by performing a P-Delta analysis. when the PDELTA ANALYSIS command is used. Given the width and depth (or diameter for circular columns) of a section.3-94 STAAD. the program will calculate the required reinforcement to resist the forces and moments. member forces are calculated which will require no user modification before beginning member design. 3A. The first method is equivalent to the procedure presented in CSA STANDARD A23. Square & Tee) For Columns .3A. 4 Design Parameters The program contains a number of parameters which are needed to perform design per CSA STANDARD A23. Depth of the concrete member.1 contains a list of available parameters and their default values. Canadian Codes . Table 3A.3-94.3-94 The second method by which STAAD allows the user to account for the slenderness effect is through user supplied moment magnification factors (see the parameter MMAG in Table 3A. which are commonly used numbers in conventional design practice. Default values. it should be done either by using the REPEAT LOAD command or by specifying the load information of these individual loading cases under one single load case.3-94 Parameters Parameter Name CLB Default Value 40mm Description Clear cover to reinforcing bar at bottom of cross section. CLS 40mm CLT 40mm DEPTH YD 122 — STAAD. All the proper factored loads must be provided by the user before the ANALYSIS specification. It is necessary to declare length and force units as Millimeter and Newton before performing the concrete design. This second procedure allows slenderness to be considered in accordance with Clause 10.3A. Here the user approximates the additional moment by supplying a factor by which moments will be multiplied before beginning member design. Note: STAAD does not factor loads automatically for concrete design. have been used for simplicity. If the effects of separate load cases are to be combined. all load cases must be defined as primary load cases. This value defaults to YD as provided under MEMBER PROPERTIES. Clear cover to reinforcing bar along the side of the cross section.Pro . This is the way STAAD works for all codes. Note: Once a parameter is specified. Usage of the LOAD COMBINATION command will yield incorrect results for P-Delta Analysis in STAAD.Pro.1-Canadian Concrete Design CSA-A23. While performing a P-Delta analysis. Table 3A.14 of the code. These parameters not only act as a method to input required data for code calculations but give the engineer control over the actual design process.Concrete Design per CSA Standard A23. Clear cover to reinforcing bar at top of cross section.1). 3A. its value stays at that specified number until it is specified again. 0 Specified compressive strength of concrete. Critical Moment will not be printed out with beam design report. Yield Stress for main reinforcing steel.0 0.Parameter Name EFACE Default Value 0.0 Face of Support Description Distance of face of support from end node of beam. Used for shear and torsion calculation. Moments will be printed. MMAG NSECTION 12 REINF SFACE 0. FC FYMAIN FYSEC MAXMAIN 30 N/mm 2 400N/mm 2 400 N/mm 2 Number 55 bar Number 10 bar Number 10 bar 1. Tied Column. A factor by which the column design moments will be magnified. Number of equally-spaced sections to be considered in finding critical moments for beam design.0 will mean spiral.0 0. MINMAIN Minimum main reinforcement bar size MINSEC Minimum secondary (stirrup) reinforcement bar size. A value of 1. Note: Both SFACE & EFACE must be positive numbers. TRACK 0.0 Note: Both SFACE & EFACE must be positive numbers. International Design Codes Manual — 123 . 1. Used for shear and torsion calculation. Yield Stress for secondary reinforcing steel. Maximum main reinforcement bar size. WIDTH ZD Width of the concrete member. Distance of face of support from start node of beam. This value defaults to ZD as provided under MEMBER PROPERTIES. END) States whether anchorage. If the section dimensions are inadequate as a singly reinforced section. effective depths of the sections are determined with the assumption of single layer of assumed reinforcement and reinforcement requirements are calculated. the user has the choice of printing reinforcements provided by STAAD at 13 equally spaced sections from which the final detailed drawing can be prepared. 124 — STAAD. FROM Distance from the start of the beam to the start of the rebar. Flexural design of beams is performed in two passes. Final provision of flexural reinforcements are made then. shear and torsion. The total number of sections considered is thirteen (start. Although exact curtailment lengths are not mentioned explicitly in the design output (which finally will be more or less guided by the detailer taking into account other practical considerations). For all these forces. Each of these sections are designed to resist the critical sagging and hogging moments.1 Design for Flexure Design for flexure is performed per the rules of Chapter 10 of CSA Standard A23. and 11 intermediate). such a message will be printed in the output. either a hook or continuation.3A. Efforts have been made to meet the guideline for the curtailment of reinforcements as per CSA Standard A23. After the preliminary design. ANCHOR (STA.3-94. Maximum sagging (creating tensile stress at the bottom face of the beam) and hogging (creating tensile stress at the top face) moments are calculated for all active load cases at each of the thirteen sections. 3A. is needed at start (STA) or at the end (END) of the bar.3-94. all active beam loadings are scanned to create moment and shear envelopes. unless that number is redefined with the NSECTION parameter. The following annotations apply to the output for Beam Design.5. reinforcing bars are chosen from the internal database in single or multiple layers.Concrete Design per CSA Standard A23. Currently. HEIGHT Height of bar level from the bottom of beam.3-94 3A. Canadian Codes . and locate critical sections. design of singly reinforced sections only is permitted. TO Distance from the start of the beam to the end of the rebar. BAR INFOrmation Reinforcement bar information specifying number of bars and size. LEVEL Serial number of bar level which may contain one or more bar group. end. In the first pass.Pro . The entire flexure design is performed again in a second pass taking into account the changed effective depths of sections calculated on the basis of reinforcement provided after the preliminary design.5 Beam Design Beams are designed for flexure. Column design is done for square. and effective depth + EFACE at the end.5. The loading which produces maximum reinforcement is called the critical load.3-94.2 Design for Shear and Torsion Design for shear and torsion is performed per the rules of Chapter 11 of CSA Standard A23. The additional longitudinal steel area required for torsion is reported. Shear design is performed at the start and end sections.5. Shear reinforcement is calculated to resist both shear forces and torsional moments. Columns are designed for axial force and biaxial moments at the ends. The load case which gives rise to the highest stirrup area for shear & torsion is chosen as the critical one.6 Column Design Column design is performed per the rules of Chapters 7 & 8 of the CSA Standard A23. This may cause slightly conservative results in some cases.0 MEMB 2 TO 9 DESIGN BEAM 2 TO 9 END CONCRETE DESIGN 3A. the reinforcement is always assumed to be equally distributed on each side. and closed hoops for beams subjected to torsion. Example of Input Data for Column Design UNIT NEWTON MMS START CONCRETE DESIGN CODE CANADIAN FYMAIN 415 ALL International Design Codes Manual — 125 . 3A. The calculations are performed assuming 2-legged stirrups will be provided.3-94. The location along the member span for design is chosen as the effective depth + SFACE at the start. For rectangular and square sections.3A. rectangular and circular sections. The stirrups are assumed to be U-shaped for beams with no torsion. All active loadings are tested to calculate reinforcement. That means the total number of bars will always be a multiple of four (4).3 Example of Input Example of Input Data for Beam Design UNIT NEWTON MMS START CONCRETE DESIGN CODE CANADA FYMAIN 415 ALL FYSEC 415 ALL FC 35 ALL CLEAR 25 MEMB 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 TRACK 1. Other parameters mentioned in Table 3A.8 of the Technical Reference Manual). Actual bar arrangement is not calculated because an element most likely represents just a fraction of the total slab area. These moments are obtained from the element force output (see Section 3.Concrete Design per CSA Standard A23.1 are relevant to slab design. The parameters FYMAIN. and CLB listed in Table 3A.1 are not applicable to slab design. Elements are designed for the moments Mx and My using the same principles as those for beams in flexure.1 . The commands for specifying elements are in accordance with the relevant sections of the Technical Reference Manual. The width of the beam is assumed to be unity for this purpose. The reinforcement required to resist Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist My moment is denoted as transverse reinforcement.3A.Element moments: Longitudinal (L) and Transverse (T) Example of Input Data for Slab/Wall Design UNIT NEWTON MMS START CONCRETE DESIGN CODE CANADA FYMAIN 415 ALL FC 35 ALL 126 — STAAD. Canadian Codes . The output consists only of area of steel required. Figure 3A. FC.7 Slab/Wall Design To design a slab or wall.3-94 FC 35 ALL CLEAR 25 MEMB 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 DESIGN COLUMN 2 TO 6 END CONCRETE DESIGN 3A. it must be modeled using finite elements. CLT. The effective depth is calculated assuming #10 bars are provided.Pro . CLB 40 ALL DESIGN ELEMENT 15 TO 20 END CONCRETE DESIGN International Design Codes Manual — 127 . 128 — STAAD.Pro 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 STAAD.Pro is capable of performing steel design based on the Canadian code CAN/CSA-S16-01 Limit States Design of Steel Structures. Design of members per CAN/CSA-S16-01 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack. 3B.1 General Comments The design of structural steel members in accordance with the specification CAN/CSA S16-01 Limit States Design of Steel Structures is can be used in STAAD.Pro. This code supercedes the previous edition of the code CAN/CSA – S16.1-94. The design philosophy embodied in this specification is based on the concept of limit state design. Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use. Two major categories of limit-states are recognized - ultimate and serviceability. The primary considerations in ultimate limit state design are strength and stability, while that in serviceability is deflection. Appropriate load and resistance factors are used so that a uniform reliability is achieved for all steel structures under various loading conditions and at the same time the probability of limits being surpassed is acceptably low. In the STAAD.Pro implementation, members are proportioned to resist the design loads without exceeding the limit states of strength, stability and serviceability. Accordingly, the most economic section is selected on the basis of the least weight criteria as augmented by the designer in specification of allowable member depths, desired section type, or other such parameters. The code checking portion of the program checks whether code requirements for each selected section are met and identifies the governing criteria. The following sections describe the salient features of the STAAD.Pro implementation of CAN/CSA-S16-01. A detailed description of the design process along with its underlying concepts and assumptions is available in the specification document. 3B.2 Analysis Methodology The elastic analysis method is used to obtain the forces and moments for design. Analysis is done for the specified primary and combination loading condition. You are allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations. Depending upon the analysis requirements, regular stiffness analysis or P-Delta analysis may be specified. Dynamic analysis may also be performed and the results combined with static analysis results. 3B.3 Member Property Specifications For specification of member properties, the steel section library available in STAAD.Pro may be used. The next section describes the syntax of commands used to assign properties from the International Design Codes Manual — 129 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 built-in steel table. Member properties may also be specified using the User Table facility. For more information on these facilities, refer to the STAAD.Pro Technical Reference Manual. 3B.4 Built-in Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. These properties are stored in a database file. If called for, the properties are also used for member design. Since the shear areas are built into these tables, shear deformation is always considered during the analysis of these members. Almost all Canadian steel sections are available for input. A complete listing of the sections available in the built-in steel section library may be obtained by using the tools of the graphical user interface. Following is the description of the different types of sections available: 3B.4.1 Welded Wide Flanges (WW shapes) Welded wide flange shapes listed in the CSA steel tables can be designated using the same scheme used by CSA. The following example illustrates the specification of welded wide flange shapes. 100 TO 150 TA ST WW400X444 34 35 TA ST WW900X347 3B.4.2 Wide Flanges (W shapes) Designation of wide flanges in STAAD is the same as that in CSA tables. For example, 10 TO 75 95 TO 105 TA ST W460X106 100 TO 200 TA ST W610X101 3B.4.3 S, M, HP shapes In addition to welded wide flanges and regular wide flanges, other I shaped sections like S, M and HP shapes are also available. The designation scheme is identical to that listed in the CSA tables. While specifying the sections, it should be remembered that the portion after the decimal point should be omitted. Thus, M310X17.6 should be specified as M310X17 and S180X22.8 should be specified as S180X22. Examples illustrating specifications of these shapes are provided below. 10 TO 20 BY 2 TA ST S510X98 45 TO 55 TA ST M150X6 88 90 96 TA ST HP310X79 130 — STAAD.Pro 3B.4.4 Channel Sections (C & MC shapes) C and MC shapes are designated as shown in the following example. As in S, M and HP sections, the portion after the decimal point must be omitted in section designations. Thus, MC250X42.4 should be designated as MC250X42. 55 TO 90 TA ST C250X30 30 TO 45 TA ST MC200X33 3B.4.5 Double Channels Back-to-back double channels, with or without spacing between them, are specified by preceding the section designation by the letter D. For example, a back-to-back double channel section C200X28 without any spacing in between should be specified as: 100 TO 120 TA D C200X28 If a spacing of 2.5 length units is used, the specification should be as follows: 100 TO 120 TA D C200X28 SP 2.5 Note that the specification SP after the section designation is used for providing the spacing. The spacing should always be provided in the current length unit. 3B.4.6 Angles To specify angles, the angle name is preceded by the letter L. Thus, a 200X200 angle with a 25mm thickness is designated as L200X200X25. The following examples illustrate angle specifications. 75 TO 95 TA ST L100X100X8 33 34 35 TA ST L200X100X20 Note that the above specification is for “standard” angles. In this specification, the local z-axis (see Fig. 2.6 in the Technical Reference Manual) corresponds to the Y’-Y’ axis shown in the CSA table. Another common practice of specifying angles assumes the local y-axis to correspond to the Y’-Y’ axis. To specify angles in accordance with this convention, the reverse angle designation facility has been provided. A reverse angle may be specified by substituting the word ST with the word RA. Refer to the following example for details. 10 TO 15 TA RA L55X35X4 The local axis systems for STANDARD and REVERSE angles is shown in Fig. 2.6 of the STAAD Technical Reference manual. International Design Codes Manual — 131 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 3B.4.7 Double Angles To specify double angles, the specification ST should be substituted with LD (for long leg back-to-back) or SD (short leg back-to-back). For equal angles, either SD or LD will serve the purpose. Spacing between angles may be provided by using the word SP followed by the value of spacing (in current length unit) after section designation. 25 35 45 TA LD L150X100X16 80 TO 90 TA SD L125X75X6 SP 2.5 The second example above describes a double angle section consisting of 125X75X6 angles with a spacing of 2.5 length units. 3B.4.8 Tees Tee sections obtained by cutting W sections may be specified by using the T specification instead of ST before the name of the W shape. For example: 100 TO 120 TA T W200X42 will describe a T section cut from a W200X42 section. 3B.4.9 Rectangular Hollow Sections These sections may be specified in two possible ways. Those sections listed in the CSA tables may be specified as follows. 55 TO 75 TA ST TUB80X60X4 In addition, any tube section may be specified by using the DT(for depth), WT(for width), and TH(for thickness) specifications. For example: 100 TO 200 TA ST TUBE DT 8.0 WT 6.0 TH 0.5 132 — STAAD.Pro will describe a tube with a depth of 8 in., width of 6 in. and a wall thickness of 0.5 inches. Note that the values of depth, width and thickness must be provided in current length unit. 3B.4.10 Circular Hollow Sections Sections listed in the CSA tables may be provided as follows: 15 TO 25 TA ST PIP33X2.5 In addition to sections listed in the CSA tables, circular hollow sections may be specified by using the OD (outside diameter) and ID (inside diameter) specifications. For example: 70 TO 90 TA ST PIPE OD 10.0 ID 9.0 will describe a pipe with an outside diameter of 10 length units and inside diameter of 9.0 length units. Note that the values of outside and inside diameters must be provided in terms of current length unit. Sample input file to demonstrate usage of Canadian shapes STAAD SPACE UNIT METER KNS JOINT COORD 1 0 0 0 17 160 0 0 MEMBER INCIDENCES 1 1 2 16 UNIT CM MEMBER PROPERTIES CANADIAN * W SHAPES 1 TA ST W250X18 * WW SHAPES 2 TA ST WW700X185 * S SHAPES 3 TA ST S200X27 * M SHAPES International Design Codes Manual — 133 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 4 TA ST M130X28 * HP SHAPES 5 TA ST HP310X132 * MC CHANNELS 6 TA ST MC150X17 * C CHANNELS 7 TA ST C180X18 * DOUBLE CHANNELS 8 TA D C250X37 SP 1.0 * ANGLES 9 TA ST L55X35X5 * REVERSE ANGLES 10 TA RA L90X75X5 * DOUBLE ANGLES, LONG LEG BACK TO BACK 11 TA LD L100X90X6 SP 2.0 * DOUBLE ANGLES, SHORT LEG BACK TO BACK 12 TA SD L125X75X6 SP 2.5 * TUBES 13 TA ST TUB120807 * TUBES 14 TA ST TUBE DT 16.0 WT 8.0 TH 0.8 * PIPES 15 TA ST PIP273X6.3 * PIPES 16 TA ST PIPE OD 16.0 ID 13.0 PRINT MEMBER PROPERTIES FINISH 3B.5 Section Classification The CSA specification allows inelastic deformation of section elements. Thus, local buckling becomes an important criterion. Steel sections are classified as plastic (Class 1), compact (Class 2), noncompact (Class 3), or slender element (Class 4) sections depending upon their local buckling characteristics (See Clause 11.2 and Table 1 of CAN/CSA-S16-01). This classification is a function of the geometric properties of the section. The design procedures are different depending on the section class. STAAD.Pro determines the section classification for the standard shapes and user specified shapes. Note: The design of Class 4 sections requires STAAD.Pro V8i (SELECTseries 2) build 2007.07 or higher. Otherwise, design is performed for sections that fall into the category of Class 1,2 or 3 sections only. 134 — STAAD.Pro 3B.6 Member Resistances The member resistances are calculated in STAAD.Pro according to the procedures outlined in section 13 of the specification. These depend on several factors such as members unsupported lengths, cross-sectional properties, slenderness factors, unsupported width to thickness ratios and so on. Note that the program automatically takes into consideration appropriate resistance factors to calculate member resistances. Explained here is the procedure adopted in STAAD.Pro for calculating the member resistances. Note: The design of Class 4 sections requires STAAD.Pro V8i (SELECTseries 2) build 2007.07 or higher. 3B.6.1 Nomenclature A = Area. A = Effective area. e f A = Area of flange. A = Area of web. w b = Effective Flange width. e C = Compressive force in a member or component under factored load. f C = Factored compressive resistance. r C = Warping torsional constant. w y C = Axial compressive load at yield stress. D = Outside diameter of pipe section. E = Elastic modulus of steel. F = Elastic critical buckling stress. e F = Yield strength. y F ye = Effective yield stress of section in compression to account for elastic local buckling. h = Clear depth of web. K = Effective length factor. L = Length or span of member. M = Bending moment in a member or component under factored load. f M = Factored moment resistance of a member. r M = Yield moment resistance. y S = Elastic section modulus. International Design Codes Manual — 135 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 S = Effective section modulus. e W = Web thickness. λ = Non-dimensional slenderness parameter in column formula. λ = Effective non-dimensional slenderness parameter in column formula considering ye effective yield stress. = Resistance factor 3B.6.2 Members Subject to Axial Forces Axial Tension The criteria governing the capacity of tension members is based on two limit states. The limit state of yielding in the gross section is intended to prevent excessive elongation of the member. The second limit state involves fracture at the section with the minimum effective net area. The net section area may be specified by the user through the use of the parameter NSF (see Table 3B.1). STAAD calculates the tension capacity of a member based on these two limits states per Cl.13.2 of CAN/CSA-S16-01. Parameters FYLD, FU, and NSF are applicable for these calculations. Axial Compression The compressive resistance of columns is determined based on Clause 13.3 of the code. The equations presented in this section of the code assume that the compressive resistance is a function of the compressive strength of the gross section (Gross section Area times the Yield Strength) as well as the slenderness factor (KL/r ratios). The effective length for the calculation of compression resistance may be provided through the use of the parameters KT, KY, KZ, LT, LY, and LZ (see Table 3B.1). Some of the aspects of the axial compression capacity calculations are : 1. For frame members not subjected to any bending, and for truss members, the axial compression capacity in general column flexural buckling is calculated from Cl.13.3.1 using the slenderness ratios for the local Y-Y and Z-Z axis. The parameters KY, LY, KZ and LZ are applicable for this. 2. For single angles, which are frame members not subjected to any bending or truss members, the axial compression capacity in general column flexural buckling and local buckling of thin legs is calculated using the rules of the AISC - LRFD code, 2nd ed., 1994. The reason for this is that the Canadian code doesn’t provide any clear guidelines for calculating this value. The parameters KY, LY, KZ, and LZ are applicable for this. 3. The axial compression capacity is also calculated by taking flexural-torsional buckling into account. The rules of Appendix D, page 1-109 of CAN/CSA-S16-01are used for this purpose. Parameters KT and LT may be used to provide the effective length factor and effective length value for flexural-torsional buckling. Flexural-torsional buckling 136 — STAAD.Pro capacity is computed for single channels, single angles, Tees and Double angles. 4. The variable “n” in Cl.13.3.1 is assumed as 2.24 for WWF shapes and 1.34 for all other shapes. 5. While computing the general column flexural buckling capacity of sections with axial compression + bending, the special provisions of 13.8.1(a), 13.8.1(b) and 13.8.1(c) are applied. For example, Lambda = 0 for 13.8.1(a), K=1 for 13.8.1(b), etc.) For Class 4 members subjected to axial compression, factored compressive resistance should be determined by either of the following equations. a. Cr= ϕAe Fy (1+λ2n )-1⁄n Where: n = 1.34 λ = √(Fy /Fe ) Fe=(π2 E)/(KL/r)2 Ae is calculated using reduced element widths meeting the maximum width to thickness ratio specified in Table 1. Effective width required for the calculation of effective area Ae, for different section shapes are as follows. l For flanges of I-section, T-section and channel section and legs of angle section be= 200t/√(Fy ) l For stem of T-section be= 340t/√(Fy ) l For flanges of HSS rectangular or Tube sections be= 670t/√((Fy ) l For circular HSS or Pipe section D= 23000t/(Fy b. Cr= ϕAFye (1+λye2n )-1⁄n Where: n = 1.34 λye = √(Fye/F_e ) Fe=(π2 E)/(KL/r)2 With an effective yield stress, F , determined from the maximum width (or diameter)ye to-thickness ratio meeting the limit specified in Table 1. Following are the expressions for effective yield stress for different shaped section. International Design Codes Manual — 137 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 l For I-section, T-section, channel section and angle section Fye= 40000/(b/t)2 l For rectangular HSS section Fye= 448900/(b/t)2 l For circular HSS section Fye= 23000/(D/t) 3B.6.3 Members Subject to Bending The laterally unsupported length of the compression flange for the purpose of computing the factored moment resistance is specified in STAAD with the help of the parameter UNL. If UNL is less than one tenth the member length (member length is the distance between the joints of the member), the member is treated as being continuously laterally supported. In this case, the moment resistance is computed from Clause 13.5 of the code. If UNL is greater than or equal to one tenth the member length, its value is used as the laterally unsupported length. The equations of Clause 13.6 of the code are used to arrive at the moment of resistance of laterally unsupported members. Some of the aspects of the bending capacity calculations are : 1. The weak axis bending capacity of all sections except single angles is calculated as For Class 1 & 2 sections, φ·Py · Fy For Class 3 sections, φ · Sy · Fy where φ = Resistance factor = 0.9 P = Plastic section modulus about the local Y axis y S = Elastic section modulus about the local Y axis y y F = Yield stress of steel 2. For single angles, the bending capacities are calculated for the principal axes. The specifications of Section 5, page 6-283 of AISC-LRFD 1994, 2nd ed., are used for this purpose because the Canadian code doesn’t provide any clear guidelines for calculating this value. 3. For calculating the bending capacity about the Z-Z axis of singly symmetric shapes such as Tees and Double angles, CAN/CSA-S16-01 stipulates in Clause 13.6(d), page 1-31, that a rational method, such as that given in SSRC’s Guide to Stability Design Criteria of Metal Structures, be used. Instead, STAAD uses the rules of Section 2c, page 6-55 of AISC-LRFD 1994, 2nd ed. 138 — STAAD.Pro Laterally Supported Class 4 members subjected to bending i. When both the web and compressive flange exceed the limits for Class 3 sections, the member should be considered as failed and an error message will be thrown. ii. When flanges meet the requirements of Class 3 but web exceeds the limits for Class 3, resisting moment shall be determined by the following equation. A h M ′ r = M r1 − 0.0005 w − Af w 1, 900 Mf/ ϕs Where Mr = factored moment resistance as determined by Clause 13.5 or 13.6 but not to exceed My = factored moment resistance for Class 3 sections = My If axial compressive force is present in addition to the moment, modified moment resistance should be as follows. 1 − 0.65C f / (ϕCy ) A h M ′ r = M r1 − 0.0005 w − 1, 900 Af w Mf/ϕs Cy = A · Fy S = Elastic section modulus of steel section. iii. For sections whose webs meet the requirements of Class 3 and whose flanges exceed the limit of Class 3, the moment resistance shall be calculated as Mr = ϕ · Se · Fy Where: S = effective section modulus determined using effective flange width. e l For Rectangular HSS section, effective flange width be= 670 · t/√(Fy ) l For I-section, T-section, Channel section, effective flange width and for Angle section, effective length width be= 200 · t/√(Fy ) But shall not exceed 60 · t Laterally Unsupported Class 4 members subjected to bending As per clause 13.6(b) the moment resistance for class-4 section shall be calculated as follows International Design Codes Manual — 139 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 i. When Mu > 0.67My M r = 1.15ϕM y 1 − 0.28M y Mu M should not exceed ϕSeFy r ii. When Mu ≤ 0.67My Mr=ϕMu Where, as per clause 13.6(a), Mu =(ω2 π)/L √(EIy GJ + (πE/L)2 Iy Cw ) For unbraced length subjected to end momentsω2 =1.75 + 1.05k + 0.3k2 ≤ 2.5 When bending moment at any point within the unbraced length is larger than the larger end moment or when there is no effective lateral support for the compression flange at one of the ends of unsupported lengthω2 = 1.0 k = Ratio of the smaller factored moment to the larger moment at opposite ends of the unbraced length, positive for double curvature and negative for single curvature. Se = effective section modulus determined using effective flange width. l For Rectangular HSS section, effective flange width be= 670t/√(Fy ) l For I-section, T-section, Channel section, effective flange width and for Angle section, effective length width be= 200t/√(Fy ) But shall not exceed 60t. This clause is applicable only for I shaped and Channel shaped section as there is no guide line in the code for other sections. 3B.6.4 Members Subject to Combined Forces Axial compression and bending The member strength for sections subjected to axial compression and uniaxial or biaxial bending is obtained through the use of interaction equations. In these equations, the additional bending caused by the action of the axial load is accounted for by using amplification factors. Clause 13.8 of the code provides the equations for this purpose. If the summation of the left hand side of these equations exceed 1.0 or the allowable value provided using the RATIO parameter (See "Design Parameters" on page 141), the member is considered to have failed under the loading condition. 140 — STAAD.Pro Axial tension and bending Members subjected to axial tension and bending are also designed using interaction equations. Clause 13.9 of the code is used to perform these checks. The actual RATIO is determined as the value of the left hand side of the critical equation. 3B.6.5 Shear The shear resistance of the cross section is determined using the equations of Clause 13.4 of the code. Once this is obtained, the ratio of the shear force acting on the cross section to the shear resistance of the section is calculated. If any of the ratios (for both local Y & Z axes) exceed 1.0 or the allowable value provided using the RATIO parameter (see Table 3B.1), the section is considered to have failed under shear. The code also requires that the slenderness ratio of the web be within a certain limit (See Cl.13.4.1.3, page 1-29 of CAN/CSA-S16-01). Checks for safety in shear are performed only if this value is within the allowable limit. Users may by-pass this limitation by specifying a value of 2.0 for the MAIN parameter. 3B.7 Design Parameters The design parameters outlined in Table 3B.1 may be used to control the design procedure. These parameters communicate design decisions from the engineer to the program and thus allow the engineer to control the design process to suit an application's specific needs. The default parameter values have been selected such that they are frequently used numbers for conventional design. Depending on the particular design requirements, some or all of these parameter values may be changed to exactly model the physical structure. Note: Once a parameter is specified, its value stays at that specified number until it is specified again. This is the way STAAD works for all codes. Table 3B.1-Canadian Steel Design CSA-S16-01 Parameters Parameter Name CODE Default Value Description International Design Codes Manual — 141 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 Parameter Name BEAM Default Value 1.0 Description 0.0 = design only for end moments and those at locations specified by SECTION command. 1.0 = Perform design for moments at twelfth points along the beam. CB 1.0 Greater than 0.0 and less than 2.5 : Value of Omega_2 (Cl.13.6) to be used for calculation. Equal to 0.0 : Calculate Omega_2 CMY 1.0 1.0 = Do not calculate Omega1 for local Y axis. 2.0 = Calculate Omega-1 for local Y axis. Used in Cl.13.8.4 of code CMZ 1.0 1.0 = Do not calculate Omega1 for local Z axis. 2.0 = Calculate Omega-1 for local Z axis. Used in Cl.13.8.4 of code 142 — STAAD.Pro Parameter Name DFF Default Value None(Mandatory for deflection check) Description “Deflection Length”/Maxm. Allowable local deflection. Joint No. denoting start point for calculation of “deflection length” Joint No. denoting end point for calculation of “deflection length” Maximum allowable depth (Applicable for member selection) Minimum required depth (Applicable for member selection) Yield strength of steel. Ultimate strength of steel. K value for flexural torsional buckling. DJ1 Start Joint of member DJ2 End Joint of member DMAX 45.0 in. DMIN 0.0 in. FYLD 300.0 MPa FU 345.0 MPa KT 1.0 International Design Codes Manual — 143 3B. Canadian Codes - Steel Design per CSA Standard CAN/CSA-S16-01 Parameter Name KY Default Value 1.0 Description K value for general column flexural buckling about the local Yaxis. Used to calculate slenderness ratio. K value for general column flexural buckling about the local Zaxis. Used to calculate slenderness ratio. Length for flexural torsional buckling. Length for general column flexural buckling about the local Yaxis. Used to calculate slenderness ratio. Length for general column flexural buckling about the local Zaxis. Used to calculate slenderness ratio. KZ 1.0 LT Member Length LY Member Length LZ Member Length 144 — STAAD.Pro Parameter Name MAIN Default Value 0.0 Description 0.0 = Check slenderness ratio against the limits. 1.0= Suppress the slenderness ratio check. 2.0 = Check slenderness ratio only for column buckling, not for web (See Section 3B.6, Shear) NSF 1.0 Net section factor for tension members. Permissible ratio of actual load effect to the design strength. 0.0 = Report only minimum design results. 1.0 = Report design strengths also. 2.0 = Provide full details of design. RATIO 1.0 TRACK 0.0 UNB Member Length Unsupported length in bending compression of the bottom flange for calculating moment resistance. International Design Codes Manual — 145 The section selected will be of the same type as that specified initially.2 MEMB 3 4 UNL 15 MEMB 3 4 RATIO 0.8 Code Checking The purpose of code checking is to check whether the provided section properties of the members are adequate. If the BEAM parameter for a member is set to 1. For example. Member selection cannot be performed on TUBES. a member specified initially as a channel will have a channel selected for it. Canadian Codes . Code checking is done using forces and moments at specified sections of the members.9 Member Selection The member selection process basically involves determination of the least weight member that PASSes the code checking procedure based on the forces and moments of the most recent analysis. location (distance from the start joint) and magnitudes of the governing forces and moments are also printed. governing load case. moments are calculated at every twelfth point along the beam. 3B. The extent of detail of the output can be controlled by using the TRACK parameter.Pro . Example of commands for MEMBER SELECTION: 146 — STAAD. When no sections are specified and the BEAM parameter is set to zero (default). PIPES or members listed as PRISMATIC.3B.Steel Design per CSA Standard CAN/CSA-S16-01 Parameter Name UNT Default Value Member Length Description Unsupported length in bending compression of the top flange for calculating moment resistance. The code checking output labels the members as PASSed or FAILed. Selection of members whose properties are originally provided from a user table will be limited to sections in the user table.85 ALL KY 1. The adequacy is checked as per the CAN/CSA-S16-01 requirements. In addition. the critical condition. design will be based on member start and end forces only. Example of commands for CODE CHECKING: UNIT NEWTON METER PARAMETER CODE CANADIAN FYLD 330E6 MEMB 3 4 NSF 0.9 ALL CHECK CODE MEMB 3 4 3B. the solved examples of the 1994 edition of the CISC Handbook have been used as reference material for these examples. CR Factored compressive resistance TR Factored tensile resistance VR Factored shear resistance MRZ Factored moment resistance (about z-axis) MRY Factored moment resistance (about y-axis) Further details can be obtained by setting TRACK to 2.0. factored member resistances will be printed.2(c) RX in that Clause) 3B.UNIT NEWTON METER PARAMETER FYLD 330E6 MEMB 3 4 NSF 0.11 Verification Problems In the next few pages are included several verification examples for reference purposes.9 ALL SELECT MEMB 3 4 3B.85 ALL KY 1.2(b) for uniaxial bending (called C CTORFLX Capacity in accordance with 13. International Design Codes Manual — 147 . CR1 CAPACITY (C ) PER 13.8.8.10 Tabulated Results of Steel Design Results of code checking and member selection are presented in a tabular format.2 MEMB 3 4 UNL 15 MEMB 3 4 RATIO 0. Since the S16-01 code is similar in many respects to the previous edition of the code (CAN/CSA S16.2(a) r CR2 CAPACITY (C ) PER 13. Following is a description of some of the items printed.8.0.194).2(b) r CRZ SEE 13.8. If the TRACK parameter is set to 1. The term CRITICAL COND refers to the section of the CAN/CSA-S16-01 specification which governed the design. Problem Find the interaction ratio.0.883 283. Kz 1.2-CAN/CSA-S16 Verification Problem 1 comparison Critera Interaction Ratio Beam Resistance (kN·m) Beam Deflection (mm) Reference STAAD.0. L/300 = 8000/300 = 27 mm Factored Uniform Load IS 7 kN/m DEAD.21-M y Simply supported beam has a 8. Canadian Codes .Pro * * Version Bld * 148 — STAAD.1 Verification Problem No.88 284 0.1-94. wide flange section. Given E = 200000 MPa (STEEL) F = 300 Mpa CSA G40. Limit States Design of Steel Structures.11. This example is included in the installation of STAAD. Steel section is W410X54 Comparison Table 3B. Ky is 1.Pro . 3D beam element.20 none none 21 20. 15 kN/m LIVE. 1994 with CISC (Canadian Institute of Steel Construction) handbook. beam resistance and beam deflection.Pro as …/SProV8i/STAAD/Examp/Can/can_ver_prob1. 1 Steel beam with uniform load.0 m span. CISC Example 1 page 5-91. National Standard of Canada.Pro Difference 0.std Reference CAN/CSA-S16.0 m Allowable Live Load deflection. Static analysis. unsupported length 1. The Canadian Standards Association.Steel Design per CSA Standard CAN/CSA-S16-01 3B.81 none STAAD Output **************************************************** * * * STAAD.3B. DISK SPACE = 12.Y.0000 -1.0000 0. Intl.0000 -2. UNIT METER KN 25. 2 8000 0 0 10.0000 0. MEMBER LOAD 27.0000 -1. STAAD SPACE VERIFICATION CISC 1994 HANDBOOK EXAMPLE PAGE 5-91 3.25DL + 1. 1 1 2 13.0000 0.0000 International Design Codes Manual — 149 . 1 UNI GY -7 29.0000 -2. * * Date= * * Time= * * * * USER ID: * **************************************************** 1. SUPPORTS 21. * SIMPLY SUPPORTED BEAM WITH UNIFORM LOAD 5. 1 0 0 0.0000 0.0000 -1. TOTAL DEGREES OF FREEDOM = 5 SIZE OF STIFFNESS MATRIX = 1 DOUBLE KILO-WORDS REQRD/AVAIL.0000 0. E STEEL ALL 18.0000 0.0000 -1.0000 -2.5471 0.0000 0.5 36. UNIT MMS KN 8.0000 -0.0000 0.0000 -1.Z DISPL FROM START TO END JOINTS AT 1/12TH PTS 1 2 0. JOINT COORDINATES 9.0000 0.0120 0.6 MB 37. PERFORM ANALYSIS P R O B L E M S T A T I S T I C S ----------------------------------NUMBER OF JOINTS/MEMBER+ELEMENTS/SUPPORTS = 2/ 1/ 2 ORIGINAL/FINAL BAND-WIDTH= 1/ 1/ 5 DOF TOTAL PRIMARY LOAD CASES = 2. LOAD 2 LIVE 30.4824 0. 1 UNI GY -15 33.8086 0.0000 0.0000 0. * CISC EXAMPLE 1 PAGE 5-91.0812 0.0000 0. LIMIT STATES DESIGN.1-94 4.0000 0.8086 0. PRINT SECTION DISPLACEMENTS MEMBER SECTION DISPLACEMENTS ---------------------------UNIT =INCHES FOR FPS AND CM FOR METRICS/SI SYSTEM MEMB LOAD GLOBAL X.* Proprietary Program of * * Research Engineers. 1 TABLE ST W410X54 16.4824 0. LOAD COMB 3 1. CSA-S16.0000 0.0000 -1.0000 0. LOAD 1 DEAD 26.0528 0.5 LL 34.0/ 19641.3 ALL 20.0000 -0. LOAD LIST 2 38. MEMBER PROPERTY CANADIAN 14. POISSON 0.0000 0.5471 0.25 2 1. 2 FIXED BUT MY MZ 24. * LIVE LOAD DEFLECTION OF L/300 7. MEMBER LOAD 31.0120 0. 1 1. 1 PINNED 22. CONSTANTS 17. MEMBER INCIDENCES 11.0528 0. 000E+00 Z AXIS = 0. FYLD 300000 ALL 46.00 OMEGA-2 = 1. Canadian Codes .77E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.08E+01 48.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 1. ST W410X54 8.00 -250.00E+02 IZ = 1.KNS MET (UNLESS OTHERWISE NOTED) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST W410X54 (CANADIAN SECTIONS) PASS CSA-13.00 4.883 3 0.0 SECTION CAPACITIES (UNIT . CHECK CODE ALL STAAD.00 OMEGA-1 (Z-AXIS) = 1.15E+02 PY = 1.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 5.00 4.08115 AT 400.732E+02 CRZ = 1.000 KL/RY = 207.805E+03 COMPRESSIVE CAPACITY = 2.KN.8. LOAD LIST 3 41.570E+03 CTORFLX = 2.604E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 1.379E+02 VRZ = 4. CODE CANADIAN 43.00 LOAD 2 L/DISP= 384 ************ END OF SECT DISPL RESULTS *********** 40.00 0. UNL 1 ALL 45.832E+02 FACTORED SHEAR RESISTANCE : VRY = 5.447 ALLOWABLE KL/R = 300.203 ************ END OF DATA FROM INTERNAL STORAGE ************ 49.000 OMEGA-1 (Y-AXIS) = 1.84E+01 MEMBER LENGTH = 8.170 KL/RZ = 48.02E+03 SY = 1.Steel Design per CSA Standard CAN/CSA-S16-01 MAX LOCAL DISP = 2.86E+04 SZ = 9.00 C 0. BEAM 1 ALL 47.846E+03 CR2 = 2.732E+02 FACTORED MOMENT RESISTANCE : MRY = 4. TRACK 2 ALL 44. STEEL TAKE OFF ALL STEEL TAKE-OFF -------------PROFILE LENGTH(METE) WEIGHT(KN ) In Steel Takeoff the density of steel is assumed for members with no density.203 PRISMATIC STEEL 0.PRO CODE CHECKING .778E+01 MRZ = 2. FINISH 150 — STAAD.(CAN/CSA-S16-01) ****************************************** ALL UNITS ARE .00 SHEAR FORCE (KNS) : Y AXIS = 0.732E+02 TENSILE CAPACITY = 1.00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 6.26E+02 PZ = 1. PARAMETER 42.0 FU = 345.05E+03 IY = 1.3B.000 ---------------TOTAL = 4.2+ 0.Pro .M) --------------------------------CR1 = 1. 3-CAN/CSA-S16 Verification Problem2 comparison Critera Interaction Ratio Beam Resistance (kN·m) Column Resistance (kN) Reference STAAD. This example is included in the installation of STAAD. Ky is 1. 3D beam element.800 3. Problem Find the interaction ratio.0.3B.std Reference CAN/CSA-S16.Pro * * Version Bld * International Design Codes Manual — 151 . 2 Steel beam/column.0 factored axial load is 2000 kN and end moments of 200 kN*m and 300 kN*m Steel section is W310X129 Comparison Table 3B. Kz 1.820 none STAAD Output **************************************************** * * * STAAD.21-M y Simply supported beam/column has a 3. wide flange section.Pro as …/SProV8i/STAAD/Examp/Can/can_ver_prob2. F = 300 MPa CSA G40.1-94.2 Verification Problem No. National Standard of Canada.11. Page 4_106. CISC Handbook Example. 1994 with CISC (Canadian Institute of Steel Construction) handbook.7 m span.98 584 2% none 3. Given E = 200000 MPa (STEEL). Limit States Design of Steel Structures.96 583 0. Static Analysis. The Canadian Standards Association. beam and column resistance.Pro Difference 0. 00 200. 2 FIXED BUT FY MY MZ 22. PRINT MEMBER FORCES MEMBER END FORCES STRUCTURE TYPE = SPACE ----------------ALL UNITS ARE -.KN METE MEMBER LOAD JT AXIAL SHEAR-Y SHEAR-Z TORSION MOM-Y MOM-Z 1 1 1 2000.00 ************** END OF LATEST ANALYSIS RESULT ************** 152 — STAAD.00 135. 2 MZ 200 27.Steel Design per CSA Standard CAN/CSA-S16-01 * Proprietary Program of * * Research Engineers. 1 1 2 11. LOAD 1 FACTORED LOAD 24. SUPPORTS 20.14 0. STAAD SPACE VERIFICATION CISC 1994 HANDBOOK EXAMPLE PAGE 4-106 2. 2 0 3. MEMBER INCIDENCES 10.14 0. Canadian Codes . TOTAL DEGREES OF FREEDOM = 5 SIZE OF STIFFNESS MATRIX = 1 DOUBLE KILO-WORDS REQRD/AVAIL.00 0.3B. E STEEL ALL 17.00 0.0/ 19641. PDELTA 3 ANALYSIS P R O B L E M S T A T I S T I C S ----------------------------------NUMBER OF JOINTS/MEMBER+ELEMENTS/SUPPORTS = 2/ 1/ 2 ORIGINAL/FINAL BAND-WIDTH= 1/ 1/ 5 DOF TOTAL PRIMARY LOAD CASES = 1. MEMBER PROPERTY CANADIAN 13. * 15.00 -135. DISK SPACE = 12. 1 MZ 300 28.7 0 8.00 2 -2000.00 0. * 5. UNIT METER KN 6. 1 0 0 0. * COMPRESSION + MAJOR AXIS BENDING 4. 1 TABLE ST W310X129 14. * 23.00 300. JOINT COORDINATES 7. Intl. * 19. * 12. * * Date= * * Time= * * * * USER ID: * **************************************************** 1.00 0.2 MB ++ Adjusting Displacements 8:54:35 ++ Adjusting Displacements 8:54:35 ++ Adjusting Displacements 8:54:35 31. POISSON STEEL ALL 18.Pro . CONSTANTS 16. * 29. 1 FIXED BUT MX MZ 21. 2 FY -2000 26. * 3. * 9. JOINT LOAD 25. 70 4.351E+02 Z AXIS = 0.0 SECTION CAPACITIES (UNIT .PARAMETER CODE CANADIAN TRACK 2 ALL FYLD 300000 ALL LY 3.2C 0.70E+02 IZ = 3.7 ALL LZ 3. 36.16E+03 IY = 1.90E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.00 300.(CAN/CSA-S16-01) ****************************************** ALL UNITS ARE .000E+00 SLENDERNESS RATIO OF WEB (H/W) = 2.980 1 2000.94E+03 PZ = 2.00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 1. 39.820E+03 TENSILE CAPACITY = 4.51E+02 PY = 9.459E+03 CR2 = 3.672E+02 MRZ = 5.359E+03 COMPRESSIVE CAPACITY = 3.505E+03 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 1.296E+03 CTORFLX = 3.00 0. 35.0 FU = 345.840E+02 FACTORED SHEAR RESISTANCE : VRY = 7.694 PRISMATIC STEEL 0. 37.65E+02 MEMBER LENGTH = 3. International Design Codes Manual — 153 . ST W310X129 3.PRO CODE CHECKING .M) --------------------------------CR1 = 4.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 3. FINISH 33.12E+01 40.8. STEEL MEMBER TAKE OFF ALL STEEL TAKE-OFF -------------PROFILE LENGTH(METE) WEIGHT(KN ) In Steel Takeoff the density of steel is assumed for members with no density.00 C 0.000 KL/RY = 47.820E+03 CRZ = 4.094 ALLOWABLE KL/R = 200.694 MEMBER PROFILE LENGTH WEIGHT (METE) (KN ) 1 ST W310X129 3.00 SHEAR FORCE (KNS) : Y AXIS = 1.KN.000 --------------- TOTAL = 4.KNS MET (UNLESS OTHERWISE NOTED) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST W310X129 (CANADIAN SECTIONS) PASS CSA-13.477 KL/RZ = 27.694 ************ END OF DATA FROM INTERNAL STORAGE ************ 42.00 0.08E+04 SZ = 1.70 4.820E+03 FACTORED MOMENT RESISTANCE : MRY = 2.7 ALL CHECK CODE ALL STAAD.700 OMEGA-1 (Y-AXIS) = 1. 38.00 OMEGA-2 = 1.419E+02 VRZ = 1.00E+04 SY = 6. 34.00 OMEGA-1 (Z-AXIS) = 1. Given E = 200000 MPa (STEEL).00 299 none none 630 650 3. Weak axis (kN·m) Beam Resistance. Lu = 3.7 m span. Strong axis (kN·m) Column Resistance (kN) Reference STAAD. 3D beam element. Steel section is W310X143. Static Analysis. Canadian Codes . Page 4-108.222 none STAAD Output **************************************************** 154 — STAAD.7 m factored axial load is 2000 kN and end moments of 200 kN*m and 300 kN*m in the strong axis and 100 kN*m at each end in the weak axis.3 Verification Problem No.0.200 4. Comparison Table 3B.Pro . CISC Handbook Example.998 300 1. 1994 with CISC (Canadian Institute of Steel Construction) handbook. Problem Find the interaction ratio.Pro as …/SProV8i/STAAD/Examp/Can/can_ver_prob3.11. National Standard of Canada.Pro Difference 0. Kz 1. wide flange section.Steel Design per CSA Standard CAN/CSA-S16-01 3B.3B. Ky is 1. Limit States Design of Steel Structures.0. This example is included in the installation of STAAD.21-M y Simply supported beam/column has a 3. beam and column resistance. The Canadian Standards Association.2% 4.std Reference CAN/CSA-S16. F = 300 MPa CSA G40.4-CAN/CSA-S16 Verification Problem 3 comparison Criteria Interaction Ratio Beam Resistance.1-94. 3 Steel beam/column. * ( COMPRESSION + BIAXIAL BENDING ) 4. TRACK 2 ALL International Design Codes Manual — 155 . JOINT COORDINATES 7. 1 MZ 300 29. STAAD SPACE VERIFICATION CISC 1994 HANDBOOK EXAMPLE PAGE 4-108 2. PARAMETER 34. * 31. E STEEL ALL 17. * 5. * 9. LOAD 1 FACTORED LOAD 24. JOINT LOAD 25. * 19. * 23. Intl. * 15. 2 MZ 200 27. CMZ 2 ALL 37. SUPPORTS 20. 1 TABLE ST W310X143 14. 1 MX 100 30. 1 FIXED BUT MX MZ 21. 1 1 2 11. * 3.0/ 19641. CB 1 ALL 38. 1 0 0 0. 2 FIXED BUT FY MX MY MZ 22. CONSTANTS 16.2 MB 33. * * Date= * * Time= * * * * USER ID: * **************************************************** 1. PERFORM ANALYSIS P R O B L E M S T A T I S T I C S ----------------------------------NUMBER OF JOINTS/MEMBER+ELEMENTS/SUPPORTS = 2/ 1/ 2 ORIGINAL/FINAL BAND-WIDTH= 1/ 1/ 6 DOF TOTAL PRIMARY LOAD CASES = 1. DISK SPACE = 12.Pro * * Version Bld * * Proprietary Program of * * Research Engineers. 2 FY -2000 26. 2 0 3. 2 MX 100 28. * 12. CMY 2 ALL 36. TOTAL DEGREES OF FREEDOM = 6 SIZE OF STIFFNESS MATRIX = 1 DOUBLE KILO-WORDS REQRD/AVAIL. MEMBER INCIDENCES 10.* * * STAAD. MEMBER PROPERTY CANADIAN 13. POISSON STEEL ALL 18.7 0 8. CODE CANADIAN 35. UNIT METER KN 6. 15E+03 PZ = 2.987E+02 MRZ = 6.037E+02 VRZ = 1.000 ---------------TOTAL = 5.00 SHEAR FORCE (KNS) : Y AXIS = 1.M) --------------------------------CR1 = 4.00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 1.171 PRISMATIC STEEL 0. 156 — STAAD. cantilever beam subjected to a uniform load.912E+03 CR2 = 4.504E+02 FACTORED SHEAR RESISTANCE : VRY = 8.802 ALLOWABLE KL/R = 200.00 0.40 OMEGA-1 (Z-AXIS) = 0.8. ST W310X143 3.700 OMEGA-1 (Y-AXIS) = 0.000 KL/RY = 47.077 KL/RZ = 26. STEEL MEMBER TAKE OFF ALL STEEL TAKE-OFF -------------PROFILE LENGTH(METE) WEIGHT(KN ) In Steel Takeoff the density of steel is assumed for members with no density.0 FU = 345.11.(CAN/CSA-S16-01) ****************************************** ALL UNITS ARE .41E+03 IY = 1.2A 1.KNS MET (UNLESS OTHERWISE NOTED) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= * 1 ST W310X143 (CANADIAN SECTIONS) FAIL CSA-13.70E+02 IZ = 3.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 3. Canadian Codes . Static analysis.00 C -100.70 5.222E+03 TENSILE CAPACITY = 4.171 MEMBER PROFILE LENGTH WEIGHT (METE) (KN ) 1 ST W310X143 3.47E+04 SZ = 2.171 ************ END OF DATA FROM INTERNAL STORAGE ************ 42.82E+02 MEMBER LENGTH = 3.351E+02 Z AXIS = 5.678E+03 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 1.Pro .0 SECTION CAPACITIES (UNIT .KN.3B.4 Verification Problem No.98E+01 41.40 OMEGA-2 = 1.00 0.000 1 2000.802E+03 COMPRESSIVE CAPACITY = 4.Steel Design per CSA Standard CAN/CSA-S16-01 39.405E+01 SLENDERNESS RATIO OF WEB (H/W) = 1.PRO CODE CHECKING .12E+04 SY = 7. FINISH 3B.00 300.912E+03 FACTORED MOMENT RESISTANCE : MRY = 2.222E+03 CRZ = 4.11E+03 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300. FYLD 300000 ALL 40. 3D beam element.737E+03 CTORFLX = 4.28E+02 PY = 1.70 5. 4 A slender. CHECK CODE ALL STAAD. 05E+05 MPa G = E/2. CSA-S16. Cw = 1. Ix = 3. Material FYLD = 300 MPa E = 2.894X104 mm 4 Moment of inertia about X axis.752X1010 mm 6 Member Length L = 2 m. page 5-91. D = 150 mm Thickness of web Tw = 7 mm Width of flange Bf = 150 mm Thickness of flange Tf = 6 mm Moment of inertia about Z axis. Given Design forces 8. Iz = 1086. Limit State Design. Unbraced length = 100mm.1-94 Problem A cantilever beam of length 4 meter is subjected to uniformly distributed load of 3 KN/Meter in both major and minor axis.0 KN (Shear-Z) Section Properties(Sect_Class-4): Area = 2766 mm 2 Depth of section.0 KNm (Bending-Z) 6.Reference CISC Example 1.0 KN (Compression) 6.0 KN (Shear-Y) 6.96X104 mm 4 Moment of inertia about Y axis. Iy = 337. Axial compression of 8 KN is also applied to the member.7378X104 mm 4 Warping constant.0 KNm (Bending-Y) 6. User defined steel section Sect_Class-4 from is assigned to the member.6 MPa International Design Codes Manual — 157 . 714 (1100/sqrt(Fy))*(1-0. 521726.94) = 521726.39*8000/(0.39*Cf/ *Cy)=(1100/sqrt(300))*(1-0.956 MPa.24 Web is Class 1.9 Slenderness ratio about Y axis. L/Ry = 57. L/Rz = 31.22 Maximum Slenderness Ratio.9*2766*300)) = 63.24*6*4+(150-2*6)*7 = 2627. Fe = π 4*E/ L_Rmax4 = 617.34))^(-1/1.76 mm 4.956 MPa. d/Tw = (150-2. Elastic critical buckling.3.5/6 = 12. L/Rmax = 57.3) Effective width. Effective yield stress. Cr = *Area*FYLDeff*(1+0. Cr = *Aeff*FYLD*(1+0.0*6)/7 = 19.697 Axial compressive resistance. Check against axial compression (Clause 13.644 Axial compressive resistance.5 > 200/sqrt(Fy) = 11. As per Clause 13. λeff = sqrt(FYLDeff/Fe) = 0.3. Beff = 200*Tf/sqrt(300) = 69.Steel Design per CSA Standard CAN/CSA-S16-01 Solution Slenderness Ratio Effective Length factor along Local Y-Axis = KY = 1 Effective Length factor along Local Z-Axis = KZ = 1 Slenderness ratio about Z axis.3(b). Axial compressive resistance Min(557886.104. 158 — STAAD. FYLDeff =40000/( 0.94 N.54 Flange is Class 4. Fe = π 4*E/ L_Rmax4 = 617. Non-dimensional slenderness ratio. As per Clause 13.34) = 557886.34))^(-1/1.3(a).3.22 Section Classification Bf/Tf = 150*0. Overall section is Class 4 section.644^(2*1. Canadian Codes .94 N. Elastic critical buckling.24 Effective area. Effective non-dimensional slenderness ratio.104 N.34) = 521726. λ = sqrt(FYLD/Fe) =0.697^(2*1.5*Bf/Tf)4 =256 MPa.Pro .3B. Aeff = 69. 24*63)/12 + 2*(2*69.549 KN-m International Design Codes Manual — 159 .12 mm 4. If the member is laterally unsupported major axis bending resistance is determined by clause 13.71 N-mm = 42. Mu = (1.752X10^10) =2.894X104*78846.24*6)*(150-6)*(150-6)/4 + (7*(150-2*6)3)/12 =10152591.79 KN-m. Effective moment of inertia about Z axis.48X108 My = Sz*FYLD = (1086.6(b).144 mm 3. Iyeff =(2*6*(2*69.15*0.856/69.88*300 =36549327.5(c)) As the web of the section meets the requirement of Class 3 and flange exceeds Class 3 limit.88 N-mm. Izeff =2*(2*69.14/2000)*sqrt(205000*337. Mrz2 = Mrz1. Minor axis bending resistance. as per clause 13.24 = 38383.6(a). Szeff = 10152591.96X104X2/150) *300 =43478400. ω2 = 1.5*(150-6)*73)/12 =2657648.28*43478400/2. Since Mu > 0.88 mm 3.154*3.856 mm 4.75.Check against bending (Clause 13.894X104*1. Mrz2 should not be more than Mrz1. Mrz2 = 36549327. flexural resistance should be calculated as per clause 13. Effective moment of inertia about Y axis.75*3. Syeff = 2657648. Mrz2 > Mrz1 in this example.65My. As the value of one of the end moments is 0.6 N-mm. Mry = *Syeff*FYLD = 0.6 N-mm = 36.iii. Where.0. Mrz1 = *Szeff*FYLD= 0. Major axis bending resistance if member is laterally supported.9*38383.7378X104 + (3.9*135367. Effective section modulus about Z axis. Effective section modulus about Y axis.12*2/150 = 135367.9*43478400*(1-0.14*205000/2000)4*337.144*300 = 10363448. Moment of resistance Mrz2 = 1.5(c). Since.24)3)/12 +(0.48X108) =42791153. Pro .XX * * Proprietary Program of * * Bentley Systems. Inc. 1 1 2 13.363 KNm 10.STD 2. 1 0 0 0.Pro V8i SELECTseries2 * * Version 20. 2 2000 0 0 11.38 KN-m none STAAD Output **************************************************** * * * STAAD. * SIMPLY SUPPORTED BEAM WITH UNIFORM LOAD 7. TABLE 1 15.1-94 6. * CISC EXAMPLE 1 PAGE 5-91.07. MEMBER INCIDENCES 12. START JOB INFORMATION 3.Pro Result 5.219X102 KN Comments Axial compressive resistance Major axis bending resistance Minor axis bending resistance none 36. * LIVE LOAD DEFLECTION OF L/300 8.5-CAN/CSA-S16 Verification Problem 4 comparison Criteria Hand Calculation 521.549 KNm 36. * * Date= AUG 17. UNIT MMS KN 9.Steel Design per CSA Standard CAN/CSA-S16-01 Comparison Table 3B.3B. WIDE FLANGE 160 — STAAD. END JOB INFORMATION 5.57 KN-m none 10.73 KN STAAD. 2010 * * Time= 17: 6:23 * * * * USER ID: Bentley * **************************************************** 1. LIMIT STATES DESIGN. Canadian Codes . START USER TABLE 14. ENGINEER DATE 16-FEB-10 4. CSA-S16.07. UNIT METER KN 16. JOINT COORDINATES 10. STAAD SPACE VERIFICATION CISC 1994 HANDBOOK EXAMPLE PAGE 5-91 INPUT FILE: s-16-01 verification example. 00105 0.7378E-008 0. 46.0018 END UNIT METER KN DEFINE MATERIAL START ISOTROPIC MATERIAL1 E 2.03 END DEFINE MATERIAL MEMBER PROPERTY 1 UPTABLE 1 SECT_CLASS-4 UNIT MMS KN CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED UNIT METER KN LOAD 1 LC1 MEMBER LOAD 1 UNI GY -3 1 UNI GZ -3 JOINT LOAD 2 FX -8 PERFORM ANALYSIS P R O B L E M S T A T I S T I C S ----------------------------------NUMBER OF JOINTS/MEMBER+ELEMENTS/SUPPORTS = 2/ 1/ 1 SOLVER USED IS THE IN-CORE ADVANCED SOLVER TOTAL PRIMARY LOAD CASES = 1. 36. PRINT MEMBER FORCES LIST 1 VERIFICATION CISC 1994 HANDBOOK EXAMPLE PAGE 5-91 -. 27. 24. 22. 25. 41.17.08696E-005 3. 40. 47. 35. TOTAL DEGREES OF FREEDOM = 6 48.3 DENSITY 76. SECT_CLASS-4 0. 34. 44. 28. 38. 37. 21.15 0.007 0.05E+008 POISSON 0. 26. 3 MEMBER END FORCES ----------------ALL UNITS ARE -.15 0.006 1. 42.8195 ALPHA 1.KN MEMBER LOAD JT STRUCTURE TYPE = SPACE METE AXIAL (LOCAL ) SHEAR-Y SHEAR-Z TORSION MOM-Y MOM-Z International Design Codes Manual — 161 . 45. 23. 19.2E-005 DAMP 0.05E+008 POISSON 0. 18.002766 0. 20. 33. 29. 43.37894E-006 3. 39.PAGE NO. 32.3 ISOTROPIC STEEL E 2. LOAD LIST 1 49. 30. 31. 760 6.00 6.00 6.00 0.00 0.00 C (UPT) CSA-13.00 -8.35E+02 3.(CAN/CSA-S16-01 ) V2.00 0.0 MPA 1.00E+02 EFFECTIVE MEMBER PROPERTIES FOR CLASS-4 SECTION(UNIT = CM) ---------------------------------------------------------EFFECTIVE CROSS SECTION AREA = 2.45E+02 3. 53.00 0.75E+04 MEMBER LENGTH = PZ = 1. 52.77E+01 1.85E+01 COMPRESSIVE CAPACITIES FOR CLASS 4 SECTION(UNIT = MPA) ------------------------------------------------------ 162 — STAAD.00 0.09E+03 SZ = 1.74E+00 CW = 1.Steel Design per CSA Standard CAN/CSA-S16-01 1 1 1 2 8.00 0. PARAMETER 1 CODE CANADIAN CB 0 ALL TRACK 2 ALL FYLD 300000 ALL CHECK CODE ALL STAAD.00 6. 54. 55.KNS MEMBER TABLE MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST SECT_CLASS-4 PASS 8.66E+02 EFFECTIVE SY = EFFECTIVE YILED STRESS = 256.3B.Pro .PRO CODE CHECKING .63E+02 PY = 6.3B -6.38E+02 SY = 4.92E+01 2.8.51E+01 3.00 1 0. 51.02E+03 EFFECTIVE SZ = EFFECTIVE IY = 2.00 0.00 -6.00 ************** END OF LATEST ANALYSIS RESULT ************** 50.63E+01 EFFECTIVE IZ = 1. Canadian Codes .00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS IZ = IY = IX = SECTION AREA = 2.0 ******************************************** ALL UNITS ARE . 084E+02 CTORFLX = 5.00 OMEGA-1 (Z-AXIS) = 1.05E+05 G = 7.657E+01 MU = 2.038E+01 MRZ = 3.2010 TIME= 17: 6:28 **** ************************************************************ * For questions on STAAD. FINISH *********** END OF THE STAAD.00 OMEGA-2 = 1.904 ALLOWABLE KL/R = 200.000E+00 Z AXIS = 6.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 1.219E+02 CRZ = 6.75 SHEAR FORCE (KNS) : Y AXIS = 6.582E+02 CRZ = 6.373E+02 CR2 = 5.871E+02 VRZ = 3.0 FU = 345.486E+02 FACTORED SHEAR RESISTANCE : VRY = 1.219E+02 CTORFLX = 5.208E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 1.219E+02 FACTORED MOMENT RESISTANCE : MRY = 1.705E+02 BASED ON EFFECTIVE YIELD STRENGTH CR1 = 6.000 KL/RY = 57.Pro RUN *********** **** DATE= AUG 17.M) --------------------------------CR1 = 6.219E+02 SECTION CLASS 4 CRZ = 6.000 OMEGA-1 (Y-AXIS) = 1.KN.BASED ON EFFECTIVE AREA CR1 = 7.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 2.97E+01 56.084E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.300E+02 COMPRESSIVE CAPACITY = 5.582E+02 5.222 KL/RZ = 31.373E+02 CR2 = 5. please contact * * Bentley Systems Offices at the following locations * * * * Telephone Web / Email * * * * USA: +1 (714)974-2500 * * UK +44(1454)207-000 * * SINGAPORE +65 6225-6158 * * EUROPE +31 23 5560560 * * INDIA +91(033)4006-2021 * International Design Codes Manual — 163 .Pro.88E+04 SECTION CAPACITIES (UNIT .219E+02 TENSILE CAPACITY = 7.098E+02 CR2 = CTORFLX = 5.0 E = 2.
[email protected] * * CHINA +86 10 5929 7000 * * THAILAND +66(0)2645-1018/19 partha.co.com * * * * Worldwide http://selectservices.com/en-US/ * * * ************************************************************ 164 — STAAD. Canadian Codes .Pro .Steel Design per CSA Standard CAN/CSA-S16-01 * JAPAN +81(03)5952-6500 http://www.bentley. The properties listed in the tables are gross section properties. the Initiation of Yielding method has been used. The Tables are currently available for the following shapes: l Channel with Lips Channel without Lips Angle with Lips Angle without Lips Z with Lips Z without Lips Hat l l l l l l Shape selection may be done using the member property pages of the graphical user interface (GUI) or by specifying the section designation symbol in the input file. Canadian Codes . 1996 Edition. The results are presented in a form of a PASS/FAIL identifier and a International Design Codes Manual — 165 .Design Per Canadian Cold Formed Steel Code S136-94 STAAD.1 Cross-Sectional Properties The user specifies the geometry of the cross-section by selecting one of the section shape designations from the Gross Section Property Tables published in the "Cold-Formed Steel Design Manual". as well as their combinations.Pro is capable of performing steel design based on the Canadian code S136-94 Specification for the Design of Cold-Formed Steel Structural Members. For laterally supported members in bending. Cold work of forming strengthening effects have been included as an option. 3C. AISI. shear. 1995. STAAD. in accordance with CSA 136. including revisions dated May. compression.2. bending. The program allows design of single (non-composite) members in tension. as applicable. Design of members per S136-94 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack. Both unreduced and effective section properties are used in the design stage.1 Code Checking The program compares the resistance of members with the applied load effects.3C. Code checking is carried out for locations specified via the SECTION command or the BEAM parameter.2 Design Procedure The following two design modes are available: 3C. 3C.Pro uses unreduced section properties in the structure analysis stage. Refer to Section 5.2 Member Selection You may request that the program search the cold formed steel shapes database (AISI standard sections) for alternative members that pass the code check and meet the least weight criterion.Resistance is calculated in accordance with Clauses 6. angle. 3C.Design Per Canadian Cold Formed Steel Code S136-94 RATIO of load effect to resistance for each member checked. Maximum Flat Width Ratios for Elements in Compression Clause 5. channel. as applicable.2 of the Technical Reference Manual for details the specification of the Code Checking command.6.2.3 of the Technical Reference Manual for details the specification of the Member Selection command.6 through 8.4. compressive limit stress based on Initiation of Yielding.4. Maximum Effective Slenderness Ratio for members in Compression Clause 5. the program leaves the member unchanged. You may choose the degree of detail in the output data by setting the TRACK parameter.e.Pro . Refer to Section 2.1 Laterally Supported Members.4.3.2.1 through 3 and 5. present design results for that section.6 of the Technical Reference Manual for general information on Member Selection. The program will then evaluate all database sections of the type initially specified (i. 6. etc.5 of the Technical Reference Manual for general information on Code Checking. (b).2.) and.3 Code Sections Implemented The program calculates effective section properties in accordance with Clauses 5.6. regardless of whether it passes the code check or not.3C. 6.48. a minimum and/or maximum acceptable depth of the member may be specified. l 166 — STAAD. Refer to Section 2. and (e) are used. Cross-sectional properties and overall slenderness of members are checked for compliance with l Clause 5. Members in tension . l l The program will check member strength in accordance with Clause 6 of the Standard as follows: l Resistance factors listed in Clauses 6. if a suitable replacement is found.. Maximum Section Depths.4. In addition.1 General.5.1 and 6.2.2 (a). If no section satisfying the depth restrictions or lighter than the initial one can be found. Canadian Codes .3 Laterally Unsupported Members.3.3. Members in bending and shear l l Resistance calculations are based on Clauses: l l 6. 3C.48.2.4.2.2 and 6. Refer to Section 5. Table 3C.1. International Design Codes Manual — 167 .6 Combined Bending and Shear in Webs.4 Point-Symmetric Sections. Singly and Doubly Symmetric Sections.4.6.1-Canadian Cold Formed Steel Design Parameters Parameter Name CODE Default Value Description - Must be specified S136.6. Note: Once a parameter is specified. 6.1.3 Singly Symmetric Sections.4. Members in compression Resistance calculations are based on Clauses: o o o o o l l l 6.6.6. 6.2 (a) and (d). l Members in compression and bending Resistance calculations are based on Clause 6. Input for the coefficients of uniform bending must be provided.4.3 General. 6.7.2 Sections Not Subject to Torsional-Flexural Buckling.48. This is the way STAAD works for all codes.1.6.5 Cylindrical Tubular Sections. 3C. 6. its value stays at that specified number until it is specified again. See section 5. Design Code to follow.6.1.6. and 6.additional limitations. 6.5 Shear in Webs.3 Design Parameters The following table contains the input parameters for specifying values of design variables and selection of design options. 6.l 6.1 of the Technical Reference Manual.4 Channels and Z-Shaped Members with Unstiffened Flanges .1. 6. effect should be included CMZ 1. Used y for Combined axial load and bending design. 5. 0. STAAD will terminate the run and ask the user to provide one of those 2 commands.Pro .3C.0 CWY 0 DMAX 1000. See CSA 136. Used z for Combined axial load and bending design. If the BEAM value is 0.0 When this parameter is set to 1. See CSA 136. Minimum depth required for the section during member selection. the adequacy of the member is determined by checking a total of 13 equally spaced locations along the length of the member.0. This rule is not enforced for TRUSS members. 6.0 168 — STAAD.4 to 1. If neither the BEAM parameter nor any SECTION command is specified. This value must be provided in the current units. Values range from 0. Values range from 0.7.2.7. and instead. DMIN 0.2.0 (default). Coefficient of equivalent uniform bending W . 6.Design Per Canadian Cold Formed Steel Code S136-94 Parameter Name BEAM Default Value Description 1.0 Maximum depth permissible for the section during member selection. Specifies whether the cold work of forming strengthening effect should be included in resistance computation. This value must be provided in the current units.0. Coefficient of equivalent uniform bending W .0. the 13 location check is not conducted. Canadian Codes . See CSA 136.0 CMY 0.4 to 1. effect should not be included 1. checking is done only at the locations specified by the SECTION command (See STAAD manual for details).2. Effective length factor for overall column buckling in the local Z-axis. Values can range from 0. It is used to compute the KL/R ratio for determining the capacity in axial compression.0 International Design Codes Manual — 169 .0 KY 1.01 (for a column completely prevented from buckling) to any user specified large value.6. Values can range from 0. Values can range from 0. restraint provided or unnecessary FU 450 MPa Ultimate tensile strength of steel in current units. It is used to compute the KL/R ratio for determining the capacity in axial compression. Effective length factor for torsional buckling.01 (for a column completely prevented from torsional buckling) to any user specified large value.2 0.Parameter Name FLX Default Value Description 1 Specifies whether torsional-flexural buckling restraint is provided or is not necessary for the member. It is a fraction and is unit-less. Effective length factor for overall column buckling about the local Yaxis. FYLD KT 350 MPa 1. It is a fraction and is unitless. Yield strength of steel in current units. See CSA 136. 6. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression.01 (for a column completely prevented from buckling) to any user specified large value. It is a fraction and is unit-less. Section subject to torsional flexural buckling and restraint not provided 1.0 KZ 1. It is input in the current units of length. It is input in the current units of length.3. 6. Values can range from 0.1. Effective length for overall column buckling in the local Y-axis. It is input in the current units of length. Values can range from 0. It is used to compute the KL/R ratio for determining the capacity in axial compression.01 (for a column completely prevented from torsional buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression.5 LY Member length LZ Member length NSF 1.Pro .3C. See CSA 136. It is input in the current units of length.01 (for a column completely prevented from buckling) to any user specified large value. See section CSA 136.4. Canadian Codes .0 STIFF Member length 170 — STAAD. Net section factor for tension members. Effective length for overall column buckling in the local Z-axis. Spacing in the longitudinal direction of shear stiffeners for stiffened flat webs. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression. Values can range from 0.Design Per Canadian Cold Formed Steel Code S136-94 Parameter Name LT Default Value Description Member length Unbraced length for twisting. 6.01 (for a column completely prevented from buckling) to any user specified large value. Prints the design summary in addition to that printed by TRACK 1 2. stiffeners do not comply with 6.4.5 International Design Codes Manual — 171 . section name. TSA 1 Specifies whether bearing and intermediate transverse stiffeners satisfy the requirements of CSA 136. and PASS/FAIL status.Parameter Name TRACK Default Value Description 0 This parameter is used to control the level of detail in which the design output is reported in the output file. 0.5 1.5. the program uses the more liberal set of interaction equations in 6. Prints only the member number. Prints member and material properties in addition to that printed by TRACK 2. 1. If true. stiffeners comply with 6. ratio. 6.6. The allowable values are: 0. 172 — STAAD.Pro . 2 Analysis Methodology Analysis is done for the primary and combination loading conditions provided by the user. the code checking portion of the program checks whether code requirements for each selected section are met and identifies the governing criteria.20 of the Technical Reference Manual) International Design Codes Manual — 173 .Wood Design Per CSA Standard CAN/CSA-086-01 STAAD. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations. Design of members per CSA 086-01 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack. In the STAAD implementation.3 Member Property Specifications A timber section library consisting of Sawn and Glulam timber is available for member property specification. Appropriate load and resistance factors are used so that a uniform reliability is achieved for the entire structure under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. 3D. member properties can be specified using the YD (depth) and ZD (width) specifications and selecting Combination and Species specifications from the built-in table. Canadian Codes . for Sawn timber the timber section library available in STAAD may be used. The assignment is done with the help of the PRISMATIC option (Refer to Section 5. The next section describes the syntax of commands used to assign properties from the built-in timber table. 3D.3D. For Glulam timber.1 General Comments The design philosophy of this specification is based on the concept of limit state design.ultimate and serviceability. The following sections describe the salient features of the STAAD implementation of CSA08601. The primary considerations in ultimate limit state design are strength and stability. A detailed description of the design process along with its underlying concepts and assumptions is available in the specification document.Pro is capable of performing timber design based on the Canadian code CSA 086-01 Wood Design Standard. Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use. Two major categories of limit-state are recognized . 3D. while that in serviceability is deflection. For specification of member properties. 174 — STAAD.3D.1 Douglas Fir-Larch The following example illustrates the specification of Douglas Fir-Larch species combination.Wood Design Per CSA Standard CAN/CSA-086-01 3D. 100 TO 150 TABLE ST DFL_SELSTR_2X2_BM 3D.4.4. 100 TO 150 TABLE ST HEM-FIR_SELSTR_2X10_BM 3D. Canadian Codes .2 Hem-Fir Designation of Hem-Fir species combination in STAAD is as follows.4. These properties are stored in a database file.4 Spruce-Pine-Fir Designation of Spruce-Pine-Fir species combination in STAAD is as follows.Pro . specifying the dimensions. 100 TO 150 TABLE ST NORTHERN_SELSTR_3X12_BM 3D. and associating the material with the member through the CONSTANTS command.4. the properties are also used for member design. Following are the description of the different types of species combination available: 3D.5 Glu Laminated timber Designation of Glu-lam timber in STAAD involves defining the material. If called for.4 Built-in Timber Section Library The following information is provided for use when the built-in timber tables are to be referenced for member property specification. 100 TO 150 TABLE ST SPF_SELSTR_3X8_BM 3D.4.3 Northern Species Designation of Northern species combination in STAAD is as follows. UNIT FEET POUND DEFINE MATERIAL START ISOTROPIC SPF_SELSTR_4X10_BM E 1224 POISSON 0. 8 18 3 0.5E-005 ALPHA 1. 7 12 6 0. 4 18 0 0.15 DENSITY 25 ALPHA 5. 9 2 6. 3 3 4. 3 12 0 0. 4 4 5. 2 2 3.4. 12 6 3.2E-011 END DEFINE MATERIAL MEMBER PROPERTY TIMBER CANADIAN 1 PRIS YD 12 ZD 6 CONSTANTS MATERIAL GLT_D. 5 24 0 0. MEMBER INCIDENCES 1 1 2. 11 4 8.7 POISSON 0.FIR-L-24F-EX E 51611.6 Example Sample input file to demonstrate usage of Canadian timber STAAD PLANE EXAMPLE FOR DIMENSIONAL LUMBER UNIT FEET POUND JOINT COORDINATES 1 0 0 0.FIR-L-24F-EX MEMB 1 3D.UNIT CM KN DEFINE MATERIAL START ISOTROPIC GLT_D. 2 6 0 0. 10 3 7. 6 6 7. 7 7 8.15 DENSITY 2. 6 6 3 0. 13 3 8.5E-006 END DEFINE MATERIAL International Design Codes Manual — 175 . 8 8 5. 5 1 6. 5 -CSA086-01) KZV size factor applicable to shear(Clause 5.2 CSA086-01) KZB Size factor applicable to bending (Clause 5.5 Member Resistance The member resistances are calculated in STAAD according to the procedures outlined in section 5 (for sawn lumber) and 6 (for Glulam) of CSA086-01.4.4.4.2-CSA086-01. Table 4.4.2 and 6.4.2 and 6.5 -CSA086-01) 176 — STAAD.3.4.4.2 CSA086-01) KST Service condition factor applicable to tension parallel to the grain (Table 5.3 and 6.3D.2.2 and 6.4.4 and 6.4.2) KH System factor (Clause 5.4.Wood Design Per CSA Standard CAN/CSA-086-01 MEMBER PROPERTY TIM CAN 1 TO 4 9 TO 11 TABLE ST SPF_SELSTR_4X10_BM 5 TO 8 12 13 TABLE ST SPF_SELSTR_4X10_BM CONSTANTS MATERIAL SPF_SELSTR_4X10_BM MEMB 1 TO 4 9 TO 11 MATERIAL SPF_SELSTR_4X10_BM MEMB 5 TO 8 12 13 PRINT MEMBER PROPERTIES FINISH 3D.2 -CSA086-01) KSV Service condition factor applicable to longitudinal shear (Table 5.2 CSA086-01) KSE Service condition factor applicable to modulus of elasticity (Table 5.4.3.2 and 6.2 and 6.4.5 and Table 5.5 and Table 5.4.2 and 6.4.4. Canadian Codes .4.4 -CSA086-01) K_T Treatment factor (Clause 5.4 -CSA086-01) KSB Service condition factor applicable to Bending at extreme fibre (Table 5.2.2 CSA086-01) KSC Service condition factor applicable to Compression parallel to the grain (Table 5.4.Pro .4.4.4.2 CSA086-01) K_SCP Service condition factor applicable to Compression perpendicular to the grain (Table 5. These depend on several adjustment factors as follows: KD Load duration factor (Clause 4.3 and Table 5.4. Explained here is the procedure adopted in STAAD for calculating the member resistances.5 CSA086-01) CHIX Curvature factor (Clause 6.5 and Table 5.2-CSA086-01) CV shear load coefficient (Table 6.5. The second limit state involves fracture at the section with the minimum effective net area.5. The net section area may be specified by the user through the use of the parameter NSF (see Table 3B.4-CSA086-01) All of these factors must be specified as input according to the classification of timber and stress grade.4A. Therefore.6.4.5.1).4.4.1).KZT size factor applicable to tension parallel to grain (Clause 5. The limit state involves fracture at the section with the minimum effective net area. 3D.6.5.5 -CSA086-01) K_ZC size factor applicable to compression parallel to grain (Clause 5. Glulam tension members are designed based on two limit states. The effective length for the International Design Codes Manual — 177 . STAAD calculates the tension capacity of a member based on this limit state per Clause 5.2 Axial Compression The compressive resistance of columns is determined based on Clause.7.4.8.5. The equations presented in this section of the code assume that the compressive resistance is a function of the compressive strength of the gross section (Gross section Area times the Yield Strength) as well as the slenderness factor (Kc).4. For Glulam timber The design of glulam tension members differs from sawn timber since CSA 086-01 assigns different specified strength for gross and net section.11 of CSA086-01. ii.5.5.5.5 CSA086-01) KZCP size factor applicable to compression perpendicular to grain (Clause 5.4 of CSA086-01. For Sawn timber The criterion governing the capacity of tension members is based on one limit state.5.6 and Clause. The net-section area may be specified by the user through the use of the parameter NSF (see Table 3B.5. The first one is the limit state of yielding in the gross section.5 and Table 5. STAAD calculates the tension capacity of a member based on these two limits states per Clause.4.6. The specified strength at net section is slightly higher than the strength of the gross section.5.5. 3D.CSA086-01) KN Notch factor(Clause 5.5 and Table 5.9 of CSA086-01.1 Axial Tension i. some or all of these parameter values may be changed to exactly model the physical structure. Clause 5.1).6 Design Parameters The design parameters outlined in Table below may be used to control the design procedure.4 of CSA086-01 and for glulam members are determined based on Clause 6. LY and LZ (see Table 3B.Wood Design Per CSA Standard CAN/CSA-086-01 calculation of compression resistance may be provided through the use of the parameters KX.10 and 6.5.5.Pro .5 and 6. KY.5. Depending on the particular design requirements.3 Bending The bending resistance of Sawn members are determined based on Clause 5. Canadian Codes .5 of CSA086-01. KZ.4 Axial compression and bending The member strength for sections subjected to axial compression and uni-axial or biaxial bending is obtained through the use of interaction equations. 178 — STAAD.5. These parameters communicate design decisions from the engineer to the program and thus allows the engineer to control the design process to suit an application's specific needs. The default parameter values have been selected such that they are frequently used numbers for conventional design. 3D. Clause 5.5.2 of the code.1). 3D. its value stays at that specified number until it is specified again. This is the way STAAD works for all codes.5.5. If the summation of the left hand side of these equations exceeds 1. the member is considered to have FAILed under the loading condition. KL to take in account whether lateral support is provided at points of bearing to prevent lateral displacement and rotation 3D.0 or the allowable value provided using the RATIO parameter (see Table 3B.12 of the code provides the equations for this purpose. 3D. the ratio of the shear force acting on the cross section to the shear resistance of the section is calculated. Note: Once a parameter is specified. the member is considered to have FAILed under the loading condition. Once this is obtained.6 Shear The shear resistance of the cross section is determined using the equations of Clause 5.5 Axial tension and bending The member strength for sections subjected to axial tension and uniaxial or biaxial bending is obtained through the use of interaction equations.0 or the allowable value provided using the RATIO parameter (see Table 3B. 3D.1).5. The allowable stress in bending is multiplied by Lateral stability factor.7. the section is considered to have failed under shear.1).3D.5.6.5.10 and 6. LX. If the summation of the left hand side of these equations exceeds 1.5.5. If any of the ratios (for both local Y & Z axes) exceed 1.0 or the allowable value provided using the RATIO parameter (see Table 3B.12 of the code provides the equations for this purpose. 2] KX 1.2.0 KSC 1.3.0 KH 1.4.4A] Load Duration Factor [Clause.4.3. Design Code to follow.2.4.2 and 6.4] Notch Factor [Clause 5.4. See section 5.0 KN KSB 1.5. Applicable for longitudinal shear [Table 5.2] KSE 1.2] Service Condition Factor for Bending at Extreme Fibre Applicable for bending at extreme fibre [Table 5.0 Service Condition Factor for Shear.1 of the Technical Reference Manual.4.0 Curvature Factor for Compression [Clause 6.2] System Factor [Clause 5.Table 3D. CHIX 1. Applicable for modulus of elasticity [Table 5. Applicable for tension parallel to grain [Table 5.4.0 Service Condition Factor for Modulus of Elasticity.4.4. Table 4.2] KSV 1.4/6.2 and 6.0 Service Condition Factor for Tension.4.0 1.5.4.4.2 and 6.0 1.6.2] Shear Load Coefficient [Table 6.4.4.7.3.2 and 6.2 and 6.0 K value for flexural torsional buckling International Design Codes Manual — 179 .4.5. Table 5.0 Service Condition Factor for Compression.2] KST 1.4.2] CV KD 1.7.51.1-Canadian Timber Design Parameters Parameter Name CODE Default Value Description - Must be specified as TIMBER CANADIAN. Applicable for compression parallel to grain [Table 5. 0 Size Factor for Tension.0 Size Factor for Shear [Clause 5. usually minor axis K value in local Z-axis.Pro . Applicable for compression perpendicular to grain [Clause 5. Applicable for compression perpendicular to grain [Clause .4.0 Length for flexural torsional buckling LY Length in local Y axis for slenderness value KL/r Length in local Z axis for slenderness value KL/r Net section factor for tension members LZ NSF 180 — STAAD.0 KZB 1.0 Treatment Factor [Clause 5.4] Size Factor for Compression.4.5 and Table 5.0 Size Factor for Compression.3D.2] K_SCP 1. Canadian Codes .4.0 K value in local Y-axis.2 and Table 6.5] Service Condition Factor for Compression. Applicable for bending [Clause.5] KZV 1.5 and Table 5.5] KZ 1.5 and Table 5.4.4.0 K_T K_ZC 1.5 and Table 5.5 and Table 5.Wood Design Per CSA Standard CAN/CSA-086-01 Parameter Name KY Default Value Description 1.4.4.4.4.5] LX Member length Member length Member length 1.3/6.5.4. Applicable for compression parallel to grain [Clause 5.0 KZCP 1.4.4.4. usually major axis Size Factor for Bending.0 1.5] KZT 1.4. Applicable for tension parallel to grain [Clause 5.5. governing load case.99 ALL KSC 0. Refer to Section 5.99 ALL CHIX 0. location (distance from the start joint) and magnitudes of the governing forces and moments are also printed.99 ALL KZT 0.4 of the Technical Reference Manual for general information on Code Checking.99 ALL K_SCP 0.99 ALL K_T 0.99 ALL KH 0.99 ALL KZB 0.51.99 ALL CHECK CODE ALL FINISH International Design Codes Manual — 181 .99 ALL RATIO 0. Refer to Section 4.99 ALL CV 0. Code checking is done using forces and moments at specified sections of the members. In addition. the critical condition.99 ALL KST 0.99 ALL KSB 0.99 ALL KZV 0.99 ALL KSE 0. PARAMETER CODE TIMBER CAN KD 0.99 ALL K_ZC 0.99 ALL KZCP 0.7 Code Checking The purpose of code checking is to check whether the provided section properties of the members are adequate.99 ALL KSV 0.99 ALL KN 0.0 Permissible Ratio of Actual to Allowable Value 3D. The adequacy is checked as per the CSA086-01 requirements.Parameter Name RATIO Default Value Description 1. The code checking output labels the members as PASSed or FAILed.2 of the Technical Reference Manual for details the specification of the Code Checking command. 8 Member Selection Member selection based CSA086-2001 is not available.9 Tabulated Results of Timber Design Results of code checking and member selection are presented in a tabular format.10 Verification Problems These verification examples are included for reference purposes.3D.Wood Design Per CSA Standard CAN/CSA-086-01 3D. Canadian Codes . 182 — STAAD. The term CRITICAL COND refers to the section of the CSA086-01 specification. which governed the design. 3D. Pu Actual Load in Compression Tu Actual Load in Tension Muy Ultimate moment in y direction Muz Ultimate moment in z direction V Ultimate shear force SLENDERNESS_Y Actual Slenderness ratio in y direction SLENDERNESS_Z Actual Slenderness ratio in z direction PY Factored Compressive capacity in y direction PZ Factored Compressive capacity in z direction T Factored tensile capacity MY Factored moment of resistance in y direction MZ Factored moment of resistance in z direction V Factored shear resistance SLENDERNESS Allowable slenderness ratio 3D.Pro . 2-CAN/CSA-086-01 Verification Problem 1 Criteria Design Strength (kN) Reference STAAD.000 LEY = 4500. 1 Determine the Canadian Glulam section column in axial compression.00 0. This example is included in the installation of STAAD.std Reference Example 4.Pro Difference 295 293. Column is effectively pinned at both ends and braced at mid-height in all direction. Canadian Wood Design Manual.000 LUZ = 9000.00 C 0.5 0.00X228. with design per Canadian wood design code (CSA:086-01).728 1 214.5.3D.00 CANADIAN GLULAM GRADE:GLT_SPRUCE-PINE-12C-E PASS CL.Pro CODE CHECKING .10.(S086) *********************** ALL UNITS ARE .Pro as …/SProV8i/STAAD/Examp/Can/canada_glulamcolumn.KN MEMBER TABLE LOADING/ LOCATION ======================================================================= 1 175.10/6.00 0. page 116.793 none Output for Member Design STAAD.5.0000 |-------------------------------------------------------------------------| | LEZ = 4500. 2001 Given Length = 9000 mm Comparison Table 3D.1 Verification Problem No.000 LUY = 9000.000mm | | | METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ FX MY RATIO/ MZ International Design Codes Manual — 183 . 3D.000 KH = 1.000 | | SLENDERNESS_Y = 19.000 KST = 1.000 | |-------------------------------------------------------------------------| 3D.000 KT = 1.000 KSB = 1.000 | | KZV = 1.000 KZCP = 1.std 184 — STAAD. Canadian Codes .000 | | Tu = 0.000 | | Muz = 0.000 K_ZC = 1.Pro as …/SProV8i/STAAD/Examp/Can/canada_glulambeam.793 | | T = 0.2 Verification Problem: 2 Determine the bending capacity of a Canadian Glulam section single span floor beam.943 | | PZ = 293. The compression edge assumed fully supported.000 CHIX = 1.000 | | SLENDERNESS = 50.Wood Design Per CSA Standard CAN/CSA-086-01 | KD = 1.000 KN = 1.000 KZB = 1. This example is included in the installation of STAAD.000 K_SCP = 1.714 | | ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 413.000 KZT = 1.10. with design per Canadian wood design code (CSA:086-01).000 | | MY = 0.Pro .000 | | CV = 1.000 | | MZ = 0.000 | | KSC = 1.000 KSE = 1.000 | | V = 0.737 | | SLENDERNESS_Z = 25.000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 214.000 | | Muy = 0.000 KSV = 1.000 | | V = 0. Pro Difference 208 208.0000 |--------------------------------------------------------------------------| | LEZ = 7500.000 | | Tu = 0.Reference Example 2.000 KST = 1.000 KN = 1.000 KT = 1.008 1 0.000 | | CV = 1.000 K_SCP = 1.529 | | ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 0.932 | | SLENDERNESS_Z = 1.000 | | KSC = 1.00X646.000 | | Muy = 0.000 | | V = 101. Dry service condition. page 59.000 KSE = 1.000 K_ZC = 1.5.00 0.000 LEY = 7500.000 | | KZV = 1.5.Pro CODE CHECKING .000 mm.000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 0.000 CHIX = 1.625 | | SLENDERNESS_Y = 16. Canadian Wood Design Manual.5/6.000 KH = 1.000mm | | | | KD = 1. 1. Standard load condition.000 LUZ = 7500.FIR-L-20F-E FAIL CL.(S086) *********************** ALL UNITS ARE .5.000 LUY = 7500.00 CANADIAN GLULAM GRADE:GLT_D.500 mm.000 KSB = 1. 2001 Given Length = 7.00 0.000 KSV = 1.776 none Output for Member Design STAAD.000 KZB = 1.00 T 0. Untreated Comparison Table 3D.000 | International Design Codes Manual — 185 .000 | | Muz = 0.000 KZCP = 1.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 130. Beam Spacing = 5.323 none 101 100.3-CAN/CSA-086-01 Verification Problem 2 Criteria Design Strength in Bending (kN·m) Design Strength in Shear (kN) Reference STAAD.000 KZT = 1. 636 none Output for Member Design STAAD.Pro .4-CAN/CSA-086-01 Verification Problem 3 Criteria Design Strength in Tension (kN) Reference STAAD.000mm | | | | KD = 1.10.3 Verification Problem No.00X266.00 0. with design per the Canadian wood design code (CSA:086-01).000 41.000 | |--------------------------------------------------------------------------| 3D.Pro Difference 257 256.00 T 0.000 LUZ = 9000.Pro as …/SProV8i/STAAD/Examp/Can/canada_glulamtension.5.000 KZB = 1.776 | | | | SLENDERNESS = 50. 2001 Given Dry service condition.000 LUY = 9000. Canadian Wood Design Manual.Wood Design Per CSA Standard CAN/CSA-086-01 | | | | | | | PZ = T = MY = MZ = V = 0.000 KSB = 1.000 LEY = 4500.0000 |--------------------------------------------------------------------------| | LEZ = 4500.000 | | KSC = 1. Canadian Codes .974 1 250. page 158.00 0. This example is included in the installation of STAAD.10/6.std Reference Example 3.000 KT = 1. 3 Determine the capacity of a Canadian Glulam section in axial tension.3D.5.000 0.000 | 186 — STAAD.000 K_SCP = 1.(S086) *********************** ALL UNITS ARE .323 100.000 KSV = 1.923 208.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 80.00 CANADIAN GLULAM GRADE:GLT_SPRUCE-PINE-14T-E PASS CL.000 KST = 1.000 KH = 1.000 KSE = 1.Pro CODE CHECKING . Untreated Comparison Table 3D.5 0. (S086) *********************** ALL UNITS ARE .000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 0.Pro as …/SProV8i/STAAD/Examp/Can/canada_sawn_lumber_column. Canadian Wood Design Manual. This example is included in the installation of STAAD.000 K_ZC = 1.000 | | T = 256.000 | | Muy = 0.000 | |--------------------------------------------------------------------------| 3D.000 KN = 1.std Reference Example 2.000 | | V = 0.| KZV = 1.000 | | PZ = 0.000 | | MZ = 0.000 | | Tu = -250. Column is effectively pinned at both ends.000 | | CV = 1.Pro CODE CHECKING .000 KZCP = 1.Pro Difference 130 129.10.000 | | Muz = 0.000 | | ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 0.000 CHIX = 1.636 | | MY = 0.000 | | V = 0.5-CAN/CSA-086-01 Verification Problem 4 Criteria Design Strength (kN) Reference STAAD.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= International Design Codes Manual — 187 . 2001 Given Unbraced Length = 5. page 113.000 mm Comparison Table 3D. with design per the Canadian wood design code (CSA:086-01). 4 Determine the Canadian Sawn section column in axial compression.000 KZT = 1.223 none Output for Member Design STAAD.4 Verification Problem No. 5 Determine the bending capacity of a Canadian sawn section single span floor beam.000 | | V = 0. This example is included in the installation of STAAD.223 | | | | T = 0.std Reference Example 1.000 KH = 1.000 KSB = 1.000 KZB = 1.050 CHIX = 1.000 | | Muz = 0.000 KZCP = 1.3D.000 | | KSC = 0.5.000 KN = 1.000 K_ZC = 1.000 | | Muy = 0. page 58.000 | | CV = 1.882 1 114.000 | | SLENDERNESS = 50.0000 |--------------------------------------------------------------------------| | LEZ = 5000.000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 114.5 Verification Problem No.10/6.10.223 3D.000 KZT = 1. Canadian Codes .000 KT = 1.000 | | MY = 0.000 KSE = 1.000 | |--------------------------------------------------------------------------| PZ = 129.Pro as …/SProV8i/STAAD/Examp/Can/canada_sawn_lumber_beam1. Beam Spacing = 3000mm.000 | | Tu = 0.178 | | SLENDERNESS_Z = 26. with design per the Canadian wood design code (CSA:086-01).00 0.000 KST = 1.000 | | SLENDERNESS_Y = 26. Dry service condition.000mm | | | | KD = 1.000 | | MZ = 0.000 LEY = 5000.5.00 0.178 | | ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 129.00 C 0.000 | | KZV = 1.000 LUZ = 5000.Pro .000 | | V = 0.12 0.910 K_SCP = 1.000 LUY = 5000. Standard load condition.000 KSV = 1.5. Canadian Wood Design Manual. 2001 Given Length =6000mm. Untreated 188 — STAAD.Wood Design Per CSA Standard CAN/CSA-086-01 1 ST DFL_NO2_8X8_POST PASS CL. 1 46.900 KZT = 1.5/6.000 LUY = 3000.000 KSB = 1.000 | | KSC = 1.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST DFL_NO1_10X16_BM FAIL CL.Pro CODE CHECKING .000 KT = 1.000 | |--------------------------------------------------------------------------| International Design Codes Manual — 189 .5.170 | | SLENDERNESS = 50.8 79.800 | | MZ = 79.5.000 K_ZC = 1.050 CHIX = 1.0000 |--------------------------------------------------------------------------| | LEZ = 3000.(S086) *********************** ALL UNITS ARE .000 | | Tu = 0.000 LEY = 3000.000 | | Muz = 49.511 | | SLENDERNESS_Z = 2.000 K_SCP = 1.158 | | ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 0.000 KZB = 0.6-CAN/CSA-086-01 Verification Problem 5 Criteria Design Strength in Bending (kN·m) Design Strength in Shear (kN) Reference STAAD.066 1 0.000 KH = 1.000 | | MY = 79.000 KST = 1.000 LUZ = 3000.200 | | SLENDERNESS_Y = 4.5.00 49.170 none Output for Member Design STAAD.200 | | V = 49.Pro Difference 79.000 | | T = 0.900 | | KZV = 0.732 none 46.20 0.000 KZCP = 1.000 | | Muy = 0.000mm | | | | KD = 1.000 | | CV = 1.000 KSE = 1.732 | | V = 46.00 T 0.000 | | PZ = 0.Comparison Table 3D.000 KN = 1.6 1.000 KSV = 1.000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 0. 338 none Output for Member Design STAAD.000 KZCP = 1.12 0.000mm | | | | KD = 1.000 KSB = 1.std Reference Example 2.10/6. 2001 Given Dry service condition.Pro .Pro Difference 185 184.000 | | KZV = 1.000 KH = 1. 6 Determine the capacity of a Canadian Sawn section in axial tension.000 KN = 1.(S086) *********************** ALL UNITS ARE .3D. Canadian Wood Design Manual.000 | | CV = 1.5.000 | | KSC = 0.Wood Design Per CSA Standard CAN/CSA-086-01 3D. page 158.000 KZT = 1.781 1 144.7-CAN/CSA-086-01 Verification Problem 6 Criteria Design Strength in Tension (kN) Reference STAAD.000 | 190 — STAAD. Canadian Codes .5.100 KT = 1. with design per the Canadian wood design code (CSA:086-01).000 LEY = 5000.10.910 K_SCP = 1.050 CHIX = 1.000 | | | | ACTUAL LOADS : (KN-m) | | Pu = 0.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST DFL_NO1_6X8_BM PASS CL.000 LUZ = 5000.00 0.000 KSV = 1.0000 |--------------------------------------------------------------------------| | LEZ = 5000.00 0.000 KST = 1.00 T 0.6 Verification Problem No.000 | | Muy = 0.Pro CODE CHECKING . Untreated Comparison Table 3D.000 LUY = 5000.000 K_ZC = 1. This example is included in the installation of STAAD.5.000 | | Muz = 0.000 KZB = 1.Pro as …/SProV8i/STAAD/Examp/Can/canada_sawn_lumber_tension.000 | | Tu = -144.000 KSE = 1.000 | | V = 0. 000 | | V = 0.338 | | MY = 0.000 | |--------------------------------------------------------------------------| International Design Codes Manual — 191 .000 | | PZ = 0.| ALLOWABLE CAPACITIES OF THE SECTION: (KN-m) | | PY = 0.000 | | T = 184.000 | | MZ = 0. 192 — STAAD.Pro . Section 4 Cypriot Codes International Design Codes Manual — 193 . 194 — STAAD.Pro . 4A. Design of members per this code requires the STAAD Eurozone Design Codes SELECT Code Pack. Cypriot Codes . International Design Codes Manual — 195 .Pro is capable of performing concrete design based on the Cyrpiot code Seismic code for reinforced concrete structures in Cyprus.Concrete Design in Cyprus STAAD. Pro .196 — STAAD. This value default is as provided as YD in MEMBER PROPERTIES. Table 4B. Table 4A. 2. Depth of concrete member. International Design Codes Manual — 197 .1 contains a complete list of available parameters with their default values. Design Code to follow. See section 5.52. DEPTH YD EFACE 0.2 of the Technical Reference Manual. Face of support location at end of beam. Note: Once a parameter is specified. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. Column unbraced in either direction. Default values of commonly used parameters for conventional design practice have been chosen as the basis.0 Bracing parameter for column design: 0. in current units. Column braced in only the local Z direction. Column braced in both directions 1. its value stays at that specified number until it is specified again. CLEAR 20 mm Clearance of reinforcement measured from concrete surface to closest bar perimeter. ELY 1.4B. in current units. 3. BRACE 0. Column braced in only the local Y direction.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to the concrete code of Cyprus.0 Note: Both SFACE & EFACE must be positive numbers.1-Cypriot Concrete Design Parameters Parameter Name CODE Default Value Description Must be specified as CYPRUS.0 Member length factor about local Y direction for column design. This is the way STAAD works for all codes. in current units. 2. (Only applicable for shear . NSE CTION 12 SERV 0. Serviceability checks: 0. Applicable to shear bars in beams. No serviceability check performed. The upper limit is 23.Parameter Name ELZ Default Value 1.0 Factor by which column design moments are magnified Number of equally-spaced sections to be considered in finding critical moment for beam design. it is for reinforcement in both directions) Yield Stress for secondary reinforcement a. 1.0 ksi FYMAIN 60 ksi FYSEC 60 ksi MAX MAIN 50 mm MINMAIN 8 mm Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 16 20 25 32 40 50 MINSEC 8 mm Minimum secondary bar size a.0 Face of support location at start of beam. in current units Yield Stress for main reinforcement. in current units. Perform serviceability check for beams as if they were cantilever beams. in current units. Applicable to shear reinforcement in beams MMAG 1. in current units (For slabs. Maximum required reinforcement bar size Acceptable bars are per MINMAIN above.0 SFACE 0. Perform serviceability check for beams as if they were simply supported.0 Description Member length factor about local Z direction for column design.use MEMBER OFFSET for bending ) 198 — STAAD. Perform serviceability check for beams as if they were continuous. FC 4.Pro . Concrete Yield Stress / cube strength. 3. For columns gives a detailed table of output with additional moments calculated. TRACK 0. 2. For beam gives min/max steel % and spacing.0 Controls level of detail in output: 0. Critical Moment will not be printed with beam design report.0 Description Skew angle considered in Wood & Armer equations where A is the angle in degrees.0 = Orthogonal reinforcement layout without considering torsional moment Mxy -slabs only -500 = Orthogonal reinforcement layout with Mxy used to calculate Wood & Armer moments for design.Parameter Name SRA Default Value 0. Two special values are also considered: 0. 1. Details of reinforcement at sections defined by the NSECTION parameter. Column design gives no detailed results. Beam design only. This value default is as provided as ZD in MEMBER PROPERTIES. International Design Codes Manual — 199 . WIDTH ZD Width of concrete member. in current units. 200 — STAAD.Pro . Section 5 Danish Codes International Design Codes Manual — 201 . Pro .202 — STAAD. Design of members per DS412 1998 requires the STAAD N.Steel Design per DS412 STAAD. International Design Codes Manual — 203 .Pro is capable of performing steel design based on the Danish code DS412 1998 Code of Practice for the structural use of steel .5A. Eurozone Design Codes SELECT Code Pack. Danish Codes . Pro .204 — STAAD. Buckling curve coefficient. Beta.0 BZ 1.0 CMY 1. about local Yaxis. Beta. Table 5B. Alpha.0 1. for hydrostatic pressure calculation for pipe members. BY 1.1-Danish Steel Design DS412 Parameters Parameter Name CODE Default Value Description Must be specified as DS412 Design Code to follow. about the local Z axis. its value stays at that specified number until it is specified again. BEAM 1. Buckling length coefficient.1 Design Parameters The design parameters outlined in Table 5A. This is the way STAAD works for all codes. some or all of these parameter values may be changed to exactly model the physical structure. Buckling curve coefficient.000 mm Maximum allowable depth (Applicable for member selection) International Design Codes Manual — 205 .0 = Calculate von Mises at twelfth points along the beam. about local Zaxis.21 CZ DMAX 1. The default parameter values have been selected such that they are frequently used numbers for conventional design. Note: Once a parameter is specified. Depending on the particular design requirements.5B. Buckling length coefficient. Water depth.1 of the Technical Reference Manual. Lateral buckling coefficient. See section 5.0 CMZ CY 0. about the local Y axis. These parameters communicate design decisions from the engineer to the program and thus allow you to control the design process to suit an application's specific needs.1 may be used to control the design procedure.48.0 CB 1. in meters. AlphaT in connection with lateral buckling. Used to calculate the ideal buckling moment. Alpha. 15 1. for local Z-axis. Report only minimum design results. FYLD 235 N/mm 2 1. Valid values between 0 and 2.0 Used to specify a level of detail in output: 0. UNL Member Length Unsupported length in bending compression of the bottom flange for calculating moment resistance. Permissible ratio of actual load effect to the design strength.0 mm Description Minimum required depth (Applicable for member selection) Yield strength of steel.0 MF RATIO Ratio of material factor to resistance factor.5. 206 — STAAD. BetaM. SSY SSZ TRACK 0. Report design strengths also. Valid values between 0 and 2.5. for local Y-axis. Equivalent moment factor.Pro .Parameter Name DMIN Default Value 0. 2. BetaM. Equivalent moment factor. Provide full details of design. 1. Section 6 Dutch Codes International Design Codes Manual — 207 . Pro .208 — STAAD. Pro is capable of performing steel design based on the Dutch code NEN 6770 TGB 1990 .1-Dutch Steel Design NEN 6770 Parameters Parameter Name Default Value Description Must be specified as DUTCH CODE Design Code to follow. BEAM 3. Check at location of maximum Mz along beam. its value stays at that specified number till it is specified again. 6A. Table 6A. This is the way STAAD works for all codes. See section 5. Used to specify the number of sections to be check along the length of the beam: 0.0 check.6A. Dutch Codes . Note: Once a parameter is specified.1 Design Parameters Available design parameters to be used in conjunction with NEN 6770 are listed in table 6A.48.1 along with their default values. 3. Check sections with end forces and forces at location of BEAM = 1. International Design Codes Manual — 209 .Steel structures .1 of the Technical Reference Manual. Check sections with end forces only. Check at every 1/13th point of the beam and report the maximum.0 1.Basic requirements and basic rules for calculation of predominantly staticaly loaded structures . 2. Eurozone Design Codes SELECT Code Pack. Design of members per NEN 6770 requires the STAAD N.Steel Design per NEN 6770 STAAD. 2 1. Fix ended member with uniform loading CMM 1. 4.0) Start Joint of member End Joint of member 10. this is the minor axis. Usually.1 and F.Pro . Fix ended member with central point load.0 3.6. the other free.1. check. DFF None (Mandatory "Deflection Length" / Maximum allowable for local deflection deflection See Note 1d in Section 2B.0 cm 1. 5. Pin ended member with uniform loading 2. Used to describe the end restraints: 1.5 = Both ends fixed.0 = No fixity CMN 1.Steel Design per NEN 6770 Parameter Name Default Value Description Loading type per Tables F. denoting starting point for calculation of "Deflection Length" . TRACK 4.0 0. See Note 1 below. See Note 1 below. Pin ended member with point loads at third points. Dutch Codes . Joint No.000 cm 0.7 = One end fixed. denoting end point for calculation of "Deflection Length". DJ1 DJ2 DMAX DMIN KY 210 — STAAD.1.6A. Pin ended member with central point load. 6.0 Joint No. Maximum allowable depth Minimum allowable depth K factor value in local y . Pin ended member with varying end moments.axis. 0. 0 Description K factor value in local z .axis. Try only those sections with a similar name as original (e. even if there are HEM’s in the same table). this is the major axis.axis (current units) to calculate (KZ)(LZ)/Rzz slenderness ratio.Parameter Name KZ Default Value 1. Length in local z . Try every section of the same type as original SAME 0. 0. if the original is an HEA 100. then only HEA sections will be selected.0 0.g. Length in local y . Controls the sections to try during a SELECT process. Grade Fe 430 2.axis (current units) to calculate (KY)(LY)/Ryy slenderness ratio.0 0.0 1.0 Member Length Member Length 1.. Grade Fe 360 1. Identify Section type for section classification SBLT 0. Net section factor for tension members. Usually. Rolled Section 1.0 Set according to steel grade (SGR) 1. Built up Section Steel Grade SGR 0. Grade Fe 510 International Design Codes Manual — 211 . LY LZ NSF PY Design strength of steel RATIO Permissible ratio of the actual capacities. Output detailed results. Output summary of results with member capacities. 2. Output summary of results.0 1. Deflection Check (separate check to main select / check code) UNL Member Length Unrestrained member length in lateral torsional buckling checks. 3. TRACK 0. Dutch Codes . 212 — STAAD.Steel Design per NEN 6770 Parameter Name Default Value Description Used to control the level output detail: 0.Pro .6A. Section 7 European Codes International Design Codes Manual — 213 . Pro .214 — STAAD. The International Design Codes Manual — 215 . These operations can be repeated by the user any number of times depending on the design requirements. European Codes . 2. General rules and rules for buildings. These documents provide alternative factors for loads and may also provide supplements to the rules in EC2. allowing Geometric Nonlinearity as well as P-Delta effects to be considered.Pro is capable of performing concrete design based on the European code EC2 ENV 1992-1-1:1991 E Eurocode 2: Design of concrete structures . 7A. STAAD provides a number of methods for analysis. The current version of EC2 implemented in STAAD adheres to the factors and rules provided in EC2 and has not been modified by any National Application Documents. 7A. Design of members per EC2 ENV 1992-1-1:1991 E requires the STAAD Eurozone Design Codes SELECT Code Pack. Part 1.4 Material Properties and Load Factors Design resistances are obtained by dividing the characteristic yield strengths. The objective of this method of design is to ensure that possibility of failure is reduced to a negligible level. reinforced or prestressed concrete used in buildings and civil engineering works.3 National Application Documents Various authorities of the CEN member countries have prepared National Application Documents to be used with EC2. provides design rules applicable to plain.Concrete Design Per Eurocode EC2 STAAD. 3. Design of concrete structures. It is based on the limit state philosophy common to modern standards. This is achieved through application of factors to both the applied loads and the material properties.2 Eurocode 2 (EC2) Eurocode 2.3 of EC2. as given in table 2. Perform the design for the member as appropriate.Part 1-1: General rules and rules for buildings. Providing appropriate parameter values if different from the default values. The code also provides guidelines on the global method of analysis to be used for calculating internal member forces and moments. 7A. 7A.1 Design Operations The main steps in performing a design operation are: 1. by the material partial safety factors γc for concrete and γs for reinforcements. Selecting the applicable load cases to be considered in the design process.7A. The parameters referred to above provide the user with the ability to allocate specific design properties to individual members considered in the design operation. the partial safety factor for the action under consideration. All active load cases will be considered in the design and reinforcements are assumed symmetrically arranged in the cross section. Slender columns are also covered in the design process.6.71 KN/mm 2 Shear Modulus.3.A to depth ratio is set according to clause 2. the program will make due allowance for the additional moment that has to be considered in the design.1 Design for flexure Reinforcement for both positive and negative moments is calculated on the basis of the section properties provided by the user. ρ = 23. This effect.5 for concrete and 1. shear and torsion. the design proceeds with a warning message given to that affect.56 KN/m 3 The magnitude of design loads is dependent on γF. G = E / 2 (1 + v) Poisson's Ratio. the limit for N. however.Pro . E = 21. 7A. Material coefficients in STAAD take the following default values unless replaced by numerical values provided in the input file.2 (5) of the code. Parabolic-rectangular stress distribution for the concrete section is adopted and as moment redistribution is not available in STAAD analysis. can be accounted for by the P-DELTA analysis option. Maximum torsional moment is also identified and incorporated in the design. Note: Sway type structures are not directly covered in the current implementation of EC2. If a particular load case causes tension in the column being designed that load case is ignored.7A. 7A. 216 — STAAD.5 Columns Columns are designed for axial compressive loads and possible moments at the ends of the member.4. European Codes . The maximum reinforcement calculated after all design load cases have been considered is then reported as the critical required area of reinforcement. 7A. Modulus of Elasticity. If the required reinforcement exceeds the maximum allowable then the section size is inadequate and a massage to that effect is given in the output.6 Beams Beams are designed for flexure. v = 0. For all these actions active load cases are scanned to create appropriate envelopes for the design process. In STAAD the user is allowed total control in providing applicable values for the factors and their use in various load combinations.15 for reinforcements.5.25 Unit weight.Concrete Design Per Eurocode EC2 magnitude in STAAD is 1. if desired. The moment MY is not considered in the design at all. This may not coincide with the slab's actual top and bottom and. which coincides with the local x direction of the element. which coincides with the local y direction of the element. reference is made to 'TOP' and BOTT' reinforcement which relates to the element's 'TOP' and 'BOTTOM' as determined from the connectivity of the element.21 in Section 1.6. Refer to Figure 1.61.2. links are combined with the shear force links and printed in a tabulated manner in the output file. The design of the slab considers a fixed bar size of 16mm in both directions with the longitudinal bar being the layer closest to the slab exterior faces. 7A. Reinforcement for torsional moments consists of stirrups combined with longitudinal bars. In cases where this may not be the case users must ensure that necessary checks are carried out.6. a message to revise the section size is given in the output file. and. of the Technical Reference Manual for additional information.3 where it is assumed the notional strut inclination is constant. 7A. International Design Codes Manual — 217 . In the main the design follows the same procedure as for flexure except that shear forces are assumed to be resisted without the provision of shear reinforcements. It is important to know that beams are designed for the flexural moment MZ only. Also. The combined magnitude of shear stress arising from shear forces and torsional moments are checked in order to establish whether the section size is adequate.4. compression reinforcement will be provided in order to satisfy the above limits. The maximum shear force that can be carried without crushing the concrete is also checked and if exceeded. transverse reinforcement.If required. If this is not the case an attempt is made to identify regions where nominal reinforcement is insufficient and appropriate reinforcement is then calculated to cover the excess design shear force.3. The output for the slab design refers to longitudinal reinforcements. 7A. where necessary.2 Design for Shear Shear reinforcement design is based on the standard method mentioned in clause 4. otherwise. Depending on the shear distribution within the member it may be possible that nominal shear reinforcement will be sufficient to cater for the design shear forces. full design is carried out and both shear links and longitudinal bars required are calculated and.3 Design for Torsion Torsional moments arising as a result of equilibrium requirements need to be designed for at the ultimate limit state. you must ensure this through the numbering scheme of the elements.7 Slabs Slabs can only be designed for if finite elements are used to represent them in the model of the structure. If section size is inadequate a massage is given in the output file. ELY 1. They are set to default values to begin with and may be altered to suite the particular structure. its value stays at that specified number until it is specified again. This is the way STAAD works for all codes. Some parameters are unit dependent and when altered. Table 8A.0 Member length factor about local Y direction for column design.8 Design Parameters Design parameters communicate specific design decisions to the program. DEPTH *YD EFACE *0.0 = Column braced in both directions. 1. the user may have to change some or all of the parameter default values.1-Concrete Design EC2 Parameters Parameter Name BRACE Default Value Description 0. Note: Once a parameter is specified. Depth of concrete member.0 = Column unbraced about local Z direction only 2.1 lists all the relevant EC2 parameters together with description and default values. Table 7A.7A. 218 — STAAD.0 0.Pro .0 = Column unbraced about local Y direction only 3. Depending on the model being designed. European Codes . the new setting must be compatible with the active "unit" specification.0 Note: Both SFACE & EFACE must be positive numbers. This value default is as provided as YD in MEMBER PROPERTIES.Concrete Design Per Eurocode EC2 7A. Face of support location at end of beam.0 = Column unbraced in both Y and Z directions CLEAR * 20mm Clearance of reinforcement measured from concrete surface to closest bar perimeter. Applicable to shear bars in beams Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 16 20 25 32 40 50 Minimum secondary bar size a. 2. 1. The upper limit is 20. FC FYMAIN FYSEC *460N/mm 2 MINMAIN 8mm MINSEC 8mm MAXMAIN 50mm MMAG 1.0 NSECTION 10 SERV 0.0 = Perform serviceability check for beams as if they were continuous. Applicable to shear reinforcement in beams Maximum required reinforcement bar size Acceptable bars are per MINMAIN above.0 International Design Codes Manual — 219 . Factor by which column design moments are magnified Number of equally-spaced sections to be considered in finding critical moment for beam design.0 * 30N/mm 2 *460 N/mm 2 Member length factor about local Z direction for column design. it is for reinforcement in both directions) Yield Stress for secondary reinforcement.Parameter Name ELZ Default Value Description 1.0 = No serviceability check performed. 3.0 = Perform serviceability check for beams as if they were simply supported. 0.0 = Perform serviceability check for beams as if they were cantilever beams. Concrete Yield Stress / cube strength Yield Stress for main reinforcement (For slabs. Concrete Design Per Eurocode EC2 Parameter Name SFACE Default Value Description *0.0 TRACK 0.0 List of design sag/hog moments and corresponding required steel area at each section of member WIDTH *ZD Width of concrete member.0 0. 1.Pro . Column design gives no detailed results. * Provided in current unit system 220 — STAAD. SRA 0. 2. This value default is as provided as ZD in MEMBER PROPERTIES.0 = Output of TRACK 1.0 = Orthogonal reinforcement layout without considering torsional moment Mxy -slabs only -500 = Orthogonal reinforcement layout with Mxy used to calculate Wood & Armer moments for design. A = Skew angle considered in Wood & Armer equations where A is the angle in degrees. (Only applicable for shear use MEMBER OFFSET for bending ) 0.7A.0 Face of support location at start of beam.0 = For beam gives min/max steel % and spacing. European Codes .0 = Critical Moment will not be printed with beam design report. For columns gives a detailed table of output with additional moments calculated. It is based on the ultimate limit states philosophy that is common to modern standards.07.1 General rules and rules for buildings. 3. 7B. Design of members per EC3 DD ENV 1993-1-1:1992 requires the STAAD Euro Design Codes SELECT Code Pack.Pro is capable of performing steel design based on the European code EC3 DD ENV 1993-1-1:1992 Eurocode 3: Design of steel structures Part 1. Part 1. The SS3 build will perform member design to this code for legacy files but has this code removed from the design codes list in the GUI. Providing appropriate ‘Parameter’ values if different from the default values. These operations can be repeated by the user any number of times depending on the design requirements. The objective of this method of design is to ensure that possibility of failure is reduced to a negligible level.xx) will not support this design code. STAAD uses the elastic method of analysis which may be used in all cases.1 Eurocode 3 DD ENV 1993-1-1:1992 (EC3 DD) The DD ENV version of Eurocode 3. Users are advised to use the EN 1993-1-1:2005 version for Eurocode 3 design. Specify whether to perform code-checking and/or member selection. Design of steel structures. 2. This is achieved through application of safety factors to both the applied loads and the material properties. These are “Simple”.1.Pro subsequent to version SS3 (20. European Codes .08. 7B. “Continuous”. and “Semi-continuous” which reflect the ability of the joints to International Design Codes Manual — 221 . Hence releases of STAAD. Selecting the applicable load cases to be considered in the design process. Also there are three types of framing referred to in EC3. Note: The DD ENV 1993-1-1:1992 code has now been officially superseded by EN 1993-11:2005. The ‘Parameters’ referred to above provide the user with the ability to allocate specific design properties to individual members or member groups considered in the design operation. Hint: Design per EC3 DD ENV 1993-1-1:1992 is also available in the Steel Design mode in the Graphical User Interface. The code also provides guidelines on the global methods of analysis to be used for calculating internal member forces and moments.7B.1 General Description The main steps in performing a design operation are: 1.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] STAAD.1 General rules and rules for buildings (EC3 DD) provides design rules applicable to structural steel used in buildings and civil engineering works. but the longitudinal axis is defined in the same way. A special case where Z-Z is the minor axis and Y-Y is the major axis is available if the SET Z UP command is used and is discussed in Section 5. The longitudinal axis of the member is defined as X and joins the start joint of the member to the end with the same positive direction. defines the principal cross-section axes in reverse to that of STAAD.Steel Design to Eurocode 3 [EN 1993-1-1:2005]" on page 237 7B.Axis convention in STAAD and EC3 7B. The current version of EC3 DD implemented in STAAD adheres to the factors and rules provided in DD ENV 1993-1-1:1992 and has not been modified by any National Application Document. 222 — STAAD. Figure 7B. Both of these axes definitions follow the orthogonal right hand rule. EC3.1. See "European Codes .Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] developing moments under a specific loading condition. Bear this difference in mind when examining the code-check output from STAAD. These documents provide alternative factors for loads and may also provide supplements to the rules in EC3. See figure below.5 of the Technical Reference Manual.3 Axes convention in STAAD and EC3 By default. In STAAD only “Simple” and “Continuous” joint types can be assumed when carrying out global analysis.Pro . 7B.2 National Application Documents Various authorities of the CEN member countries have prepared National Application Documents to be used with EC3.2 Analysis Methodology Elastic analysis method is used to obtain the forces and moments for design.7B. Analysis is done for the primary and combination loading conditions provided by the user. European Codes .1.1 . however. STAAD defines the major axis of the cross-section as Z-Z and the minor axis as YY. Note: National Annex documents are available for EC3 BS EN 1993-1-1:2005. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations. 7B.4 Section Classification The occurrence of local buckling of the compression elements of a cross-section prevents the development of full section capacity. However. For each load case considered in the design process. Also built-up user sections that are class 4 sections are not dealt with in the current version of EC3 design in STAAD. G = E/2(1+ ν) Poisson’s Ratio. The magnitude of Γm in STAAD is 1. The main requirement for a beam is to have sufficient cross-section resistance to the applied International Design Codes Manual — 223 . A separate safety factor parameter named GB1 is used to check the resistance of a member to buckling and also has a default value of 1.8 KN/m3 The magnitude of design loads is dependent on Γ . Design resistances are obtained by dividing the characteristic yield strength by the material partial safety factor Γm.7B. and RECTANGULAR HOLLOW SECTIONS.3. 7B.1. The EC3 DD design module in STAAD can design members with all section profiles that are of Class 1 2 or 3 as defined in section 5.3 Material Properties and Load Factors The characteristic yield strength of steel used in EC3 DD design is based on table 3. the partial safety factor for the action f under consideration.Pro.1 of the code. Laced and battened members are not considered in the current version of EC3 DD design module in STAAD.Pro considers members that are primarily in bending and/or shear as beams and performs cross section and member capacity checks in accordance with the code.3 Unit weight. E = 205000 N/mm2 Shear Modulus.2 of the code. STAAD determines the section class and calculates the capacities accordingly. ν = 0. SINGLE ANGLE.Pro. Cross sections are classified in accordance with their geometrical properties and the stress pattern on the compression elements.5 Member Design 7B.1 Design of Beams as per DD ENV 1993-11:1992 EC3 DD design in STAAD. the design of members that have a ‘Class 4’ section profile are limited to WIDE FLANGE. Material coefficients for steel in STAAD take the following default values unless replaced by user’s numerical values provided in the input file.1 which is applicable to all section types. In STAAD the user is allowed total control in providing applicable values for the factors and their use in various load combinations. SINGLE CHANNEL. TEE. Γ = 76. Modulus of Elasticity. It is therefore imperative to establish this possibility prior to determining the section capacities.5. In such cases the web is assumed to resist the applied shear force as well as contributing towards the moment resistance of the cross-section. For members with class 1 2 or 3 section profiles. the combined bending and shear checks are done in STAAD as per clause 5.2 Design of Axially Loaded Members The design of members subject to tension loads alone are performed as per Cl 5. material factor Γm and crosssectional area of the member with possible reduction due to bolt holes. The bending capacity is primarily a function of the section type and the material yield strength and is determined according to Cl. because of interaction between shear force and bending moment. 5. the full section area is considered in calculating the section capacity. which is calculated in STAAD as per the method given in Annex F of the code.4.3 of the code. Class 4 sections do suffer from local buckling and explicit allowance must be made for the reduction in section properties before the moment capacity can be determined. The tension capacity is calculated based on yield strength. and RECTANGULAR HOLLOW SECTIONS.2 and the yield strength is replaced with the ultimate tensile strength of the material. Class 3 sections.4. When bolt holes need to be considered in the capacity calculations the value used for Γm is 1.4. the moment resistance of the cross-section may be reduced. 7B. The possibility of lateral-torsional buckling is also taken into consideration when the full length of the member has not been laterally restrained. cannot develop plastic moment capacity and the yield stress is limited to the extreme compression fibre of the section. SINGLE CHANNEL. the design of class 4 sections is limited to WIDE FLANGE. 5. In cases where the members are subject to combined bending and shear.4. Class 1 and 2 sections can both attain full capacity with the exception that the class 2 sections cannot sustain sufficient rotation required for plastic analysis of the model. due to local buckling.3.5 of the code. restraint conditions and type of applied loading. The buckling capacity is dependent on the section type as well as the unrestrained length. Hence the full plastic section modulus is used in the design calculations. The shear capacity and the corresponding shear checks are done as per section 5. European Codes . Mcr.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] bending moment and shear force.5 of the code. The elastic section modulus is used to determine the moment capacity for class 3 sections.4.6 of the code.6 of the code.5. TEE. Further. However in case of class 4 sections.2 of the code.Pro .4 of the code. however. There are four classes of cross-sections defined in EC3. The lateral torsional buckling checks involves the calculation of the ‘Elastic critical moment’. As mentioned in the previous section. In the presence of a shear force. beams are also checked for shear as per section 5.4.7B. The tension capacity is then taken as the smaller of the full section capacity and the reduced section capacity as stated above. This. Beams are also checked for lateral-torsional buckling according to section 5. The effective section properties are worked out as described in Cl.5. The design of members subject to axial compression loads alone are performed as per Cl 5.7 of the code. the ‘effective cross- 224 — STAAD. does not occur unless the value of applied shear forces exceeds 50% of the plastic shear capacity of the section. SINGLE ANGLE. The a-a and b-b axes are determined by which leg of the angle is fixed by the connection and should be specified using the LEG parameter. Also any additional moments induced in the section due to the shift of the centroidal axis of the effective section will also be taken into account as per clause 5. The effective length in the a-a axis is taken as LY · KY and the effective length in the b-b axis as LZ · KZ. if not specified. Lvv. a-a and b-b. u-u and v-v and two geometric.Axis orientation for single angles ST angle and USER table angles RA angle International Design Codes Manual — 225 .6 for more information on the LEG parameter.5 of the code. The following diagram shows the axes for angles which have been defined with either an ST or RA specification and is connected by its longer leg (i. buckling resistance will also be checked for such members.3. 5. 4. Cl.8. In addition to the cross section checks. double channels or Tee sections and does give a method to work out the slenderness of such members.5. double angles. The effective length for the v-v axis. the EC3 DD design module of STAAD. a-a axis is parallel to the longer leg). The buckling capacity is calculated as per Cl.5 of the code.Pro uses the methods specified in BS 5950-1:2000 to calculate the slenderness of these members.4. The effective section properties for class 4 sections will be worked out as given in Cl.3 of the code.2 .e. This is often the critical case as the buckling strength of the member is influenced by a number of factors including the section type and the unbraced length of the member. see section 5B. Figure 7B.10 and table 25 of BS 5950-1:2000 are used in the current version of the EC3 DD design module Single Angle Sections Angle sections are un-symmetrical and when using BS 5950:2000 table 25 you must consider four axes: two principal. DD ENV 1993-1-1:1992 does not specifically deal with single angle. is taken as the LVV parameter or LY · KY.section’ is considered to calculate the compressive strength.7.. In these cases. The presence of large shear force can also reduce the bending resistance of the section under consideration. double channels or Tee sections and does give a method to work out the slenderness of such members. Some parameters are unit dependent and when altered. there is provision to take the stabilizing effect of the tension load into consideration. axial load and bending moment then the section capacity checks will be done as per Cl. European Codes . Depending on the model being designed. EC3 requires checking cross-section resistance for local capacity and also checking the overall buckling capacity of the member. 5.4. then the reduction due to shear has to be taken into account before calculating the effect of the axial load on the bending resistance of the section. 5. the member will be checked as per the rules in section 5. This is then checked against the lateral-torsional buckling resistance of the section.4. If the member is subject to a combined shear.4.7. In these cases.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] 7B. If the shear load is large enough to cause a reduction in bending resistance. Class 1 and class 2 sections are checked as per cl.4. 5.8. Table 8B. Cl. The effective section properties for class 4 sections are worked out as given in Cl.7B.3 respectively. the new setting must be compatible with the active “unit” specification. 5.Pro.Pro uses the methods specified in BS 5950-1:2000 to calculate the slenderness of these members.3 of the code. The EC3 DD design module in STAAD takes such a scenario into account and performs the necessary checks as per Cl.4. In the case of members subject to axial tension and bending.8. the user may have to change some or all of the parameter default values.Pro .5 of the code.1 and Class 3 and Class 4 sections are checked as per clauses 5.3. 226 — STAAD.9 of the code.1 lists all the relevant EC3 parameters together with description and default values. 7B. They are set to default values to begin with and may be altered to suite the particular structure.5. the EC3 DD design module of STAAD. The checks are done as per Cl. Please note that laced or battened compression members are not dealt within the current version of EC3 DD design module in STAAD. 5.3 Design of members with combined axial load and bending The bending resistance of members could be reduced by the presence of a co-existent axial load.2 for St and RA angle specifications.8.8 of the code. As stated in the previous section. In case of a combined axial compressive load and bending moment.2 and 5. Please refer to the note in section 5B. double angles.10 of BS 5950-1:2000 is used in the current version of the EC3 DD design module. 4.6 Design Parameters Design parameters communicate specific design decisions to the program.5.5. DD ENV 1993-1-1:1992 does not specifically deal with single angle.4 of the code. Generally.5. This is achieved by modifying the extreme compression fibre stress and calculating an effective applied moment for the section. Check sections with end forces and forces at location of BEAM 1. Check at every 1/13th point along the beam and report the maximum Refer to Note 2 below. Valid values range from 1 to 6. CAN 0 Member will be considered as a cantilever type member for deflection checks.0 check. Design Code to follow. See section 5. BEAM 3 Parameter to control the number of sections to checked along the length of a beam: 0. Check at location of maximum Mz along beam 2. Default Value Description International Design Codes Manual — 227 .2 for more information on its use. 3.1-Steel Design Parameters EC3 DD Parameter Name CODE Undefined You must specify EC3 or EUROPE.48. Refer to Table 5B. Check sections with end forces only 1. 0 indicates that member will not be treated as a cantilever member 1 indicates that the member will be treated as a cantilever member CMM 1.1 of the Technical Reference Manual.0 Indicates type of loading on member.Table 7B. 1 Corresponds to the Γ ENV 1993-1-1:1992 m2 factor in DD KY KZ 1. K factor in local z axis.0 = No fixity 0.5 = Full fixity 0.1 Partial safety factor used in buckling checks for compression members GM0 1. 228 — STAAD. denoting end point for calculation of "Deflection Length".0 cm Maximum allowable depth for the member. Ultimate tensile strength of steel DJ2 End Joint of member FU GB1 1.0 K factor in local y axis.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] Parameter Name CMN Default Value Description 1. DFF None (Mandatory for deflection check) Deflection limit DJ1 Start Joint of member Joint No. denoting starting point for calculation of "Deflection Length". DMIN 0 Minimum required depth for the member. Joint No.0 Indicates the level of End-Restraint.0 1. 1. European Codes .7B.7 = One end free and other end fixed DMAX 100.Pro .1 Corresponds to the Γ ENV 1993-1-1:1992 m1 factor in DD GM2 1.1 Corresponds to the Γ ENV 1993-1-1:1992 m0 factor in DD GM1 1. 3. 6. RATIO 1 Permissible ratio of loading to capacity.0 Indicates if the section is rolled or built-up. SBLT 0.3 0.0 = Built-up International Design Codes Manual — 229 .0 Connection type Refer to Note 1 below. Include additional PN EN checks See "Clause 6.0 Net tension factor for tension capacity calculation. kyz. 0. NSF 1.0 = Rolled 1. kzy. and kzz" on page 330 PY Yield Strength The yield strength default value is set based on the default value of the "SGR" parameter. LVV Maximum of Lyy and Lzz (Lyy is a term used by BS5950) Buckling length for angle about its principle axis LY Member Length Compression length in local y axis. Ignore additional PN EN checks 1.3.Parameter Name LEG Default Value Description 0. Slenderness ratio = (KZ)*(LZ)/(Rzz) PLG 0 (Polish NA only) Perform additional checks per Cl.3(5) – Interaction factors kyy. Slenderness ratio = (KY)*(LY)/(Ryy) LZ Member Length Compression length in local z axis. 0 = minimum 1 = intermediate 2 = maximum 4 = perform a deflection check See note 3 below.3(2)] Notes: 1. 0.2).5.5(A).8 Specifies a reduction factor for vectoral effects to be used in axial tension checks [Cl 5. ZIV 0. LEG – (Ref: Table 25 BS5950) The slenderness of single and double angle.7B. To define the appropriate connection. European Codes .Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] Parameter Name SGR Default Value Description 0. channel and tee sections are specified in BS 5950 table 25 depending on the connection provided at the end of the member (Refer to section 5B. The following table indicates the value of the LEG parameter required to match the BS5950 connection definition: 230 — STAAD.0 = Fe 360 1.Pro . UNF 1.0 Steel grade as per table 3. a LEG parameter should be assigned to the member.1 in EC3.0 = Fe 510 TRACK 0 Controls the level of detail of output.0 Unsupported buckling length as a factor of the beam length UNL Member Length Unrestraint length of member used in calculating the lateral-torsional resistance moment of the member.0 = Fe 430 2. 0 4.0 4.0 5.7.0 4.2 bolts long leg short leg 1.Table 7B.2 bolts short leg long leg 3.10.10.2 or more rows of bolts (b) .0 (b) .2-LEG Parameter values Clause Bold Configuration (a) .7.0 7.2 Single Angle short leg long leg 3.0 0.0 4.0 6.1 bolts short leg long leg 2.5 Tee Sections (a) .0 (d) .2 or more rows of bolts (b) .1 row of bolts 1.0 2.10.1 row of bolts 0.0 4.0 (b) .2 bolts Leg LEG Parameter 1.1 bolts long leg short leg 0.0 1.7.1 bolts short leg long leg 0.4 Channels (a) .0 International Design Codes Manual — 231 .3 Double Angles (a) .7.10.0 (c) . slenderness is calculated for the two principal axes y-y and z-z only. by setting the LEG parameter to 10. (Refer to Section 1.3-Values for the CMM Parameter CMM Value 1 Loading and Support Conditions 2 3 4 232 — STAAD. In addition.7. if using double angles from user tables.Torsional Buckling.7B. a-a and b-b as well as the weak v-v axis. the LVV parameter is available to comply with note 5 in table 25. Table 7B. Alternatively for single angles where the connection is not known or Table 25 is not appropriate. rvv. European Codes . The effective lengths of the geometric axes are defined as: La = KY * KY Lb = KZ * LZ The slenderness calculated for the v-v axis is then used to calculate the compression strength pc for the weaker principal axis (z-z for ST angles or y-y for RA specified angles). should be supplied at the end of the ten existing values corresponding to the radius of gyration of the single angle making up the pair. For double angles. The LVV parameter is not used. BEAM Ensure that this parameter is set to either 1 or 2 while performing code checking for members susceptible to Lateral . 2.3 of the Technical Reference Manual) an eleventh value.Pro . the slenderness is calculated for the geometric axes. The maximum slenderness of the a-a and b-b axes is used to calculate the compression strength pc for the stronger principal axis.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] For single angles. Code checking is done using the forces and moments at specific sections of the members. 7B. the members included in a CHECK CODE command will be checked for the local axis deflection rather than for the stress capacity using the current LOAD LIST.CMM Value 5 Loading and Support Conditions 6 3. then 2 parameter blocks with code checks are required. International Design Codes Manual — 233 .7 Code Checking The purpose of code checking is to ascertain whether the provided section properties of the members are adequate. 1. If both stress capacity and deflection checks are required. thus: LOAD LIST 1 TO 10 PARAMETER 1 CODE EN 1993 TRACK 2 ALL CHECK CODE MEMBER 1 *************************** LOAD LIST 100 TO 110 PARAMETER 2 TRACK 4 ALL DFF 300 MEMB 1 DJ1 1 MEMB 1 DJ2 4 MEMB 1 CODE MEMB 1 Note: While both sets of code checks will be reported in the output file. only the last code check results are reported in the GUI. one with a TRACK 4 command and one with a TRACK 0. or 2. Checking beam deflection With the TRACK parameter set to 4. The adequacy is checked as per DD ENV 1993-1-1:1992. Selection of members. there will be an asterisk (*) mark on front of the member.4 or any of the user defined sections as described in Section 1.9 Tabulated Results of Steel Design For code checking or member selection. Member selection cannot be performed on members whose section properties are input as prismatic or as the limitations specified in section 5. and the location (distance from the start of the member of forces in the member where the critical condition occurs). Code checking can be done with any type of steel section listed in Section 2B. whose properties are originally input from a user created table. Member selection can also be constrained by the parameters DMAX and DMIN. the governing load case. Refer to Section 5.0 or any other specified RATIO value). CRITICAL COND refers to the clause in DD ENV 1993-1-1:1992 code which governs the design.Pro . the program calculates and prints whether the members have passed or failed the checks.7(A) Code Checking. The EC3 DD design module does not consider these sections or PRISMATIC sections in its design process.Steel Design to Eurocode 3 [DD ENV 1993-1-1:1992] When code checking is selected. 7B. will be limited to sections in the user table. TABLE refers to steel section name. The items in the output table are explained as follows: MEMBER refers to the member number for which the design is performed.8 Member Selection STAAD is capable of performing design operations on specified members. Refer to Section 2. with two exceptions.5 of the Technical Reference Manual for general information on Code Checking.48. RESULTS prints whether the member has PASSED or FAILED. GENERAL and ISECTION.3 of the Technical Reference Manual. Once an analysis has been performed. the lightest section.2 of the Technical Reference Manual for details the specification of the Code Checking command.e. the value of the ratio of the critical condition (overstressed for value more than 1.7.. the critical condition . If the RESULT is FAIL. 7B. The section selected will be of the same type section as originally designated for the member being designed.B. Member selection can be performed with all the types of steel sections with the same limitations as defined in section 5B. European Codes . which fulfills the code requirements for the specified member. which limits the maximum and minimum depth of the members. i. 234 — STAAD. the program can select the most economical section. which has been checked against the steel code or has been selected. the program produces the results in a tabulated fashion.7(A).7B. which governed the design. in most cases. section class. moment in local Y-axis and the moment in local z-axis respectively. the module will also report all the relevant clause checks that have been performed and will also indicate the critical ratio and the load case that caused the critical ratio as well as the corresponding forces that were used for the respective checks. International Design Codes Manual — 235 . MY and MZ are printed since they are the ones which are of interest. A TRACK 2 output will also include the various design data used for the calculations such as the section modulii. FX. Note: For a TRACK 2 output. LOADING provides the load case number. MY. Normally a value of 1. section capacity etc. and MZ provide the axial force. only FX.RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition.0 or less will mean the member has passed. LOCATION specifies the actual distance from the start of the member to the section where design forces govern. Although STAAD does consider all the member forces and moments (except torsion) to perform design. 236 — STAAD.Pro . The code also provides guidelines on the global methods of analysis to be used for calculating internal member forces and moments. International Design Codes Manual — 237 .1 General rules and rules for buildings (EN 1993) provides design rules applicable to structural steel used in buildings and civil engineering works. and “Semi-continuous” which reflect the ability of the joints to developing moments under a specific loading condition. 2. Providing appropriate ‘Parameter’ values if different from the default values.1 General Description The main steps in performing a design operation are: 1. 7C. The objective of this method of design is to ensure that possibility of failure is reduced to a negligible level. These operations can be repeated by the user any number of times depending on the design requirements.7C. The current version of EC3 (EN 1993)implemented in STAAD adheres to the factors and rules provided in EN 1993-1-1:2005. 7C.Steel Design to Eurocode 3 [EN 1993-1-1:2005] STAAD. 7C. STAAD uses the elastic method of analysis which may be used in all cases. The ‘Parameters’ referred to above provide the user with the ability to allocate specific design properties to individual members or member groups considered in the design operation. Design of steel structures.Pro is capable of performing steel design based on the European code EC3 BS EN 19931-1:2005 Eurocode 3: Design of steel structures Part 1.2 National Annex Documents Various authorities of the CEN member countries have prepared National Annex Documents to be used with EC3.EN 1993-1-1:2005 (EN 1993) The EN 1993 version of Eurocode 3.1. “Continuous”. 3. Selecting the applicable load cases to be considered in the design process.1 Eurocode 3 . Design of members per EC3 BS EN 1993-1-1:2005 requires the STAAD Euro Design Codes SELECT Code Pack. This is achieved through application of safety factors to both the applied loads and the material properties. Part 1. In STAAD only “Simple” and “Continuous” joint types can be assumed when carrying out global analysis.Pro includes the following National Annexes viz. Also there are three types of framing referred to in EC3. These are “Simple”.1 General rules and rules for buildings.1. It is based on the ultimate limit states philosophy that is common to modern standards. Specify whether to perform code-checking and/or member selection. These documents provide alternative factors for loads and may also provide supplements to the rules in EC3. The current version of STAAD. European Codes . Steel Design to Eurocode 3 [EN 1993-1-1:2005] a. Both of these axes definitions follow the orthogonal right hand rule. Norwegian National Annex [NS-EN 1993-1-1:2005/NA2008] d.Axis convention in STAAD and EC3 See "Example of a TRACK 2 output" on page 281 for an example of how this appears when Y is up (default). but the longitudinal axis is defined in the same way. Bear this difference in mind when examining the code-check output from STAAD.5 of the Technical Reference Manual. Polish National Annex [PN EN 1993-1-1:2005] g. The longitudinal axis of the member is defined as X and joins the start joint of the member to the end with the same positive direction. defines the principal cross-section axes in reverse to that of STAAD. European Codes . See figure below. STAAD defines the major axis of the cross-section as Z-Z and the minor axis as YY. The Dutch National Annex [NEN-EN 1993-1-1/NB] and c. 7C. however. Belgian National Annex [NBN EN 1993-1-1:2005] The choice of a particular National Annex is based on the value of a new NA parameter that is set by the user when specifying the EN 1993 version of Eurocode 3. Figure 7C.1 . 7C.2 Analysis Methodology 238 — STAAD.3 Axes convention in STAAD and EC3 By default. A special case where Z-Z is the minor axis and Y-Y is the major axis is available if the SET Z UP command is used and is discussed in Section 5. See "European Codes National Annexes to Eurocode 3 [EN 1993-1-1:2005]" on page 283 for a description of the NA parameter. French National Annex [Annexe Nationale a la NF EN 1993-1-1:2005] e. EC3.Pro . Finnish National Annex [SFS EN 1993-1-1:2005] f. Singaporean National Annex [SS EN 1993-1-1:2005] h. British National Annex [NA to BS EN 1993-1-1:2005] b.7C.1. Design resistances are obtained by dividing the characteristic value of a particular resistance by the global partial safety factor for the resistance. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations.Elastic analysis method is used to obtain the forces and moments for design. However. 6. ν = 0. It is therefore imperative to establish this possibility prior to determining the section capacities. The EC3 (EN 1993) design module in STAAD can design members with all section profiles that are of Class 1.3 Unit weight. 7C.4 Section Classification The occurrence of local buckling of the compression elements of a cross-section prevents the development of full section capacity. It is worth noting that the section class reported in the design output corresponds to the most critical loadcase among those being considered for design. the design of members that have a Class 4 section profile are limited to: l l l l l l wide flange tee single channel single angle rectangular hollow sections circular hollow sections International Design Codes Manual — 239 .8 KN/m 3 The magnitude of design loads is dependent on γ .3 Material Properties and Load Factors The characteristic yield strength of steel used in EC3 (EN 1993) design is based on table 3. or 3 as defined in section 5.1 of EN 1993-1-1:2005 and can change depending on the selected National Annex. the program determines the section class and calculates the capacities accordingly.5 of the code. the partial safety factor for the action under f consideration. Γ = 76. Analysis is done for the primary and combination loading conditions provided by the user. You are allowed total control in providing applicable values for the factors and their use in various load combinations. 7C. Cross sections are classified in accordance with their geometrical properties and the stress pattern on the compression elements. For each load case considered in the design process.1 of the code. γ . E = 205000 N/mm 2 Shear Modulus. Material coefficients for steel in STAAD take the following default values unless replaced by user’s numerical values provided in the input file. The magnitude of γ is m m based on Cl. G = E/2(1+ ν) Poisson’s Ratio. Modulus of Elasticity. 2. Pro.2. SINGLE ANGLE. The cross section capacity will be checked as given in section 6. 6. The current version also does not support the design of tapered section profiles or I-Sections with top and/or bottom plates. unless they are defined as any of the section types given above.Pro uses Non-Contradictory Complimentary Information (NCCI) documents as explained in the following corresponding sections. TEE. is used for code check or selection of all cross sections and shapes listed in Section 7C.Pro . The design philosophy and procedural logistics are based on the principles of elastic analysis and ultimate limit state design. 6. Member selection is done on the basis of selecting the most economic section on the basis of the least weight criteria. etc. STAAD. Members are proportioned to resist the design loads without exceeding the characteristic stresses or capacities.4.Pro.2.2. you should control the design and verify results through the use of the design parameters. such as the provision of stiffeners. and check the local effects like flange buckling.1 Members Subject to Axial Loads The cross section capacity of tension only members is checked for ultimate limit state as given in Cl. SINGLE CHANNEL.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Also built-up user sections that are class 4 sections are not dealt with in the current version of EC3 design in STAAD. web crippling. It is generally assumed that you (the engineer) will take care of the detailing requirements. The design of laced and battened members is not considered in the current version of EC3 (EN 1993) design module in STAAD.4. 6. 7C. The effective section properties are evaluated as described in Cl.4 of the code.3 of the code. However.2. You are allowed complete control over the design process through the use of the parameters listed in Table 7C. 7C. together with any specified National Annex. where EN 1993 or the National Annex has not specified a method or values for a specific clause or parameter. European Codes .7C. The compression member stability will be verified as: 240 — STAAD.5 Member Design EN 1993-1-1:2005. and RECTANGULAR & CIRCULAR HOLLOW SECTIONS. Note: The design of class 4 (slender) sections is limited to WIDE FLANGE. However. Two major failure modes are recognized: l l failure by overstressing failure by stability considerations The following sections describe the salient features of the design approach. Lateral stability of a pure compression member will be checked as per the method given in Cl.5.5 of the code. Default values of parameters will yield reasonable results in most circumstances.3 of the code. Compression members will be checked for axial capacity of the cross section in addition to lateral buckling/stability. is taken as the LVV parameter or LY · KY. The effective length for the v-v axis.2 will be used when selecting the buckling curve. or 3 cross-sections for Class 4 cross-sections χ A efff y γ M1 Where: χ is the reduction factor as given in section 6. The buckling curves used to evaluate the reduction factor are selected from Table 6. the effective length will be taken as the member length.Pro uses the methods specified in BS 5950-1:2000 to calculate the slenderness of these members. N . The non-dimensional slenderness ¯λ for these T members is evaluated per Cl. if not specified. Even if you have specified a custom yield strength (using the PY parameter). a-a and b-b. the choice of a buckling curve will be based on the value of SGR parameter. for such members. KY.12 of the code.Rd ≤ 1. 4. The maximum slenderness among the flexural buckling slenderness. or Tee sections and does not provide a method to evaluate the slenderness of such members.T cr. The elastic torsional buckling load. N . Single Angle Sections Angle sections are un-symmetrical and when using BS 5950:2000 table 25 you must consider four axes: two principal. are evaluated based on the cr. The a-a and b-b axes are determined by which leg of the angle is fixed by the connection and should be specified using the LEG parameter. and the elastic torsional-flexural buckling load.10 and Table 25 of BS 59501:2000 are used in the current version of the Eurocode 3 design module. the effective length will be calculated as KZ*LZ for length about the Z-Z axis and KY*LY for length about the Y-Y axis. Note: Only the five grades of steel given in table 6. torsional slenderness. χ. Cl. 2. see section 5B.3.1. Compression members that are susceptible to torsional or torsional flexural buckling are checked for these modes of failure as well. double angles. 6. The effective length for the members can be controlled using the KZ. By default. In these cases. Rd = Nb.0 Where N b. LZ and LY parameters. and torsional-flexural slenderness is used to evaluate the reduction factor. The steel grade used for this selection is based on the SGR design input parameter (See "Design Parameters" on page 264). u-u and v-v and two geometric.6 for more information on the LEG International Design Codes Manual — 241 .7. double channels.3.Rd is the design buckling resistance given by: χA f y γ M1 Nb.N Ed N b . Lvv. EN 1993-1-1:2005 does not specifically deal with single angle. the EC3 (EN 1993) design module of STAAD. If these parameters are specified.TF method given in the NCCI “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” (unless otherwise specified by a particular National Annex).2 of the code based on the cross section type and the steel grade. Rd = for Class 1.4 of the EN 1993 code. Steel Design to Eurocode 3 [EN 1993-1-1:2005] parameter.7C. Rd = M c.2 Members Subject to Bending Moments The cross section capacity of a member subject to bending is checked as per Cl . European Codes .minf y γ M0 for class 4 cross-sections Cross sectional bending capacity checks will be done for both major and minor axis bending moments. Rd = M el. Rd = W eff .2 . The condition to be satisfied is: M Ed M c .6.0 Where M c. a-a axis is parallel to the longer leg)..5 of the code. Members subject to major axis bending will also be checked for Lateral Torsional Buckling resistance as per Section 6. The following diagram shows the axes for angles which have been defined with either an ST or RA specification and is connected by its longer leg (i. Rd = M pl.Axis orientation for single angles ST angle and USER table angles RA angle 7C.Rd is the is the design resistance given by: W plf y γ M0 M c.2.3. The effective length in the a-a axis is taken as LY · KY and the effective length in the b-b axis as LZ · KZ. The design buckling resistance moment M will b.Rd ≤ 1. Rd = M c.5.m inf y γ M0 for class 1 and 2 cross-sections for class 3 cross-sections W el .Rd be calculated as: 242 — STAAD.Pro .2 of the code.e. Figure 7C. Hence.2. the program will check if the National Annex expands on Cl.2.3 to calculate χ .2. If so. Singapore & Polish NAs).3. This reduction factor is LT evaluated per Cl. If the NA method does not deal with a specific condition while working out kc.2.3 for I Sections and Cl 6.3. if a LT particular National Annex has been specified. If you want the program to calculate kc.3 of the EN 1993 code depending on the section type. For all other cases the program will use Cl.3. For I sections. 6.2 or Cl 6.3 to evalute χ and for all other sections the program will resort to Cl 6. Setting MTH to 0 (default value) will cause the program to choose Cl. The non-dimensional slenderness λ (used to evaluate χ ) for both the above cases is LT LT evaluated as: λLT = W yf y M cr Where: M is the elastic critical moment for lateral torsional buckling. 6.3.3.2.3.3 to include sections other than I Sections. Note: You have the option to choose the clause to be used to calculate χLT through the MTH design parameter. 6. Rd = χLT Wy fy γ M1 Where: χ is the reduction factor for lateral torsional buckling. the program will by default use Cl.2. International Design Codes Manual — 243 . When using Cl.3 by default. the program will consider the correction LT factor kc (Table 6. Note: If the National Annex specifies a different method to calculate kc (e.2.6.2. the program will use Cl. the program will make use cr of the method specified in Annex F of DD ENV 1993-1-1 to evaluate M by cr default. 6.2.5). As mentioned above.2. you must explicitly set the value of the KC parameter to zero.2. thus ensuring that kc is considered for the particular NA.2.3.0.2. the program will use that method by default even if the KC parameter has not been explicitly set to zero. By default the value of KC will be taken as 1. However. 6. the British. 6. 6. EN 1993-1-1 does cr not however specify a method to evaluate M .3.M b.3 (Table 6. 6.3.3 for the cross-section(s) included in Cl.2.6 of EN 1993-1-1:2006) based on the value of the KC parameter in the design input.3. the program will then fall back to table 6.2 for all other section types.5) to include sections other than I sections. if the National Annex expands on Cl.6.2. the program will use Cl.3.2.3 (or Table 6.6 of the code.3.g. 1(2) of EN 1993-1-5 as is as given as follows: 244 — STAAD. the program will use the NCCI document SN-003a-EN-EU for doubly symmetric sections and SN030a-EN-EU for mono-symmetric sections that are symmetric about their weak axis. Shear stresses induced from torsional loads are taken into account while performing torsion checks.3 Members Subject to Shear The cross section capacity of a member subject to shear is checked as per Cl. the program will perform the shear buckling checks as given in Section 5 of EN 1993-1-5.Pro .2.08) and later. the program will resort to the method as per Cl. The condition to be satisfied is: VEd Vc . (See "European Codes National Annexes to Eurocode 3 [EN 1993-1-1:2005]" on page 283 for specific details). In cases where cr Annex F does not provide an adequate method to evaluate Mcr.6 of BS 5950-1:2000 to calculate the lateral torsional buckling resistance moment (Mb. the calculation of M (and λ ) will be cr LT done based on the specific National Annex.Rd is the is the shear design resistance given by: Vc.5. The shear buckling checks will be done only for I –Sections and Channel sections. 6. Rd = Vpl.6 of the code.4. Shear Buckling For sections that are susceptible to shear buckling. The susceptibility of a section to shear buckling will be based on the criteria given in Cl 5.7C.3.Rd) for the member. such as for Channel sections.0 Where: V c. Rd = Av fy / γ M0 ( 3 ) A is the shear area and is worked out for the various section types as given in v Cl.2.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Note: The method specified in Annex F will be used only when the raw EN 1993-1-1:2005 code is used without any National Annex. If the National Annex does not specify a particular method or specify a reference document.07.6(3) of the code.Rd ≤ 1. If a National Annex has been specified. Note: Web shear buckling is checked in STAAD.Pro V8i (SELECTseries 3) (release 20. European Codes . 7C. 6. For all other sections types the program will use Annex F of DD ENV 1993-1-1 to calculate M . 4 ⋅ t ϵ w Rigid End Post η 0. The design resistance is calculated as: Vb.37/(0. For stiffened webs. the section must be checked for shear buckling.Rd utilized by bending moment.0 for other steel grades k as defined in sections below τ χ is the web contribution factor obtained from Table 5.83/η 0. if hw/t > 72ε/η.2x flange w thickness). This is calculated as: Vb. Rd ≤ Vbw . Rd = Vbw.83/λw 0.1-Evaluate of χ Slenderness Parameter λw < 0.83/λw b.2 for steel grades up to and including S 460 and = 1.1 of the EC3 code w and is evaluated per the following table: Table 7C. International Design Codes Manual — 245 . The design resistances considers tension field action of the web and flanges acting as struts in a truss model. For unstiffened webs. t = thickness of the web ε = √(235/fy ).08 λw > 1. Rd = Vbw. depth ..7 + λw) Non-rigid End Post η 0. where fy is the yield stress η = 1. the section must be checked for shear buckling.5. if hw/t > 31·E√kτ/η.08 λw = hw 86. Rd ≤ η f yw wt 3 γ M1 Where: V is the flange resistance per Cl.83/λw 1.e. Rd + Vbf .a.4 for a flange not completely bf. Rd = χ wf ywh wt 3 γ M1 η f yw wt 3 γ M1 Where: h = distance between flanges of an I Section (i.83/η ≤ λw < 1. the moment of resistance of the cross section consisting of the effective area of the flanges only.7C.Rd 2 b is the width of the flange which provides the least axial resistance. f1 f2 c = a 0. f Mf. respectively.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Vbf . this is evaluated as b·tf·hw. is present.07 or later. The equation of c is likewise used to solve for a sufficient stiffener spacing in the case of demand from loads exceeding the calculated capacity for a specified stiffener spacing.6b ft f f yf 2 2 th w f yw a = transverse stiffener spacing. Ed the value of M is reduced by multiplying by the following factor: f. N . 246 — STAAD. Note: The shear forces due to any applied torsion will not be accounted for if the TOR parameter has been specifically set to a value of 0 (i. European Codes . ignore torsion option).Rd ≤ 1.Pro .25 + 1.. For a typical I Section or PFD. t is the thickness of the flange which provides the least axial resistance.5. 7C. When an axial load. then the program assumes that the member end forms a non-rigid post (case c) and proceeds to evaluate the minimum stiffener spacing required.Rd 1− N Ed A + A f f 2 f1 yf γ M0 A and A are the areas of the top and bottom flanges.4 Members Subject to Torsion Note: This feature requires STAAD. Rd = h ft f2f yf cγ M 1 M 1 − Ed M f .0 Where: V Ed is the design shear force. If the stiffener spacing has not been provided (using the STIFF parameter).Pro V8i (SELECTseries 2) build 2007. The following equation must be satisfied for the web shear buckling check to pass: η3 = VEd Vb .e. not f to be taken greater than 15εtf on each side of the web.k /γM0 .Rd = Mf. 7(5) EC-3 -6 App A Note: STAAD. The NCCI document “SN007b-EN-EU: Torsion” will also be referenced where appropriate.7(9) Cl. Also. there is no guidance on section classification nor on how to allow for the effects of local buckling on the design resistance for combined torsional effects. Furthermore. While both elastic and plastic analyses are permitted generally.7(1) Cl. the design analysis methods for torsion discussed within EC3 are primarily based on elastic methods.Pro is therefore based on the SCI publication “P057: Design of members subject to combined bending and torsion”. The method used by STAAD. EN 1993-1-6 considers such a condition in Appendix A.1 in the code) can be used for elastic verification. this clause is used primarily for this implementation. EC3 also does not specifically deal with members subject to combined bending and torsion and loosely states that the yield criteria (Eqn 6.Pro. STAAD. 6.pro uses Appendix A of EN 1993-1-6 to check for members subject to combined torsion and LTB.2.2. SCI are in the process of updating document P057 to be in accordance with Eurocode 3. only the first yield design resistance is specifically discussed for torsion members. Though this publication is based on the British standard BS 5950-1.7) to report the output for all torsion checks. However. Therefore. Note: At the time this feature has been implemented in STAAD. 6. Code Basis Torsion design in EC3 is given in Cl.2. 6.2. The following clauses from EC3 are then considered: l l l l Cl. use this clause (6. Therefore.Pro does.7 of EN 1993-1-1:2005. the principles from this document are applied in the context of Eurocode 3. however.2. EN 1993-1-1:2005 does not deal with members subject to the combined effects of torsion and lateral torsional buckling. 6. Hence this method might be subject to modifications subject to the publication of a newer version of P057.General Eurocode 3 (EN 1993-1-1:2005) gives very limited guidance for the analysis and design of torsion members. International Design Codes Manual — 247 . Also any distortional deformations and any amplification in the torsional or shear stresses due to distortions will be neglected by the program. Pro .Rd ≤ 1. This will be facilitated by setting the value of the TORSION. the design torsional moment T at each Ed cross section should satisfy: TEd / RRd ≤ 1. 6.7(5) of EN 1993-1-1. l Cl. CHS). only deal with I/H sections. and structural hollow sections (RHS. Channel sections. STAAD. for the various cases Rd is dealt in the following sections. however. the application of Cl. The TORSION parameter set to zero by default. the program will ignore torsion checks if there is no torsional moment in the member).7(1) States that for members subject to torsion..T. Basic Stress Check: This method is intended to be a simplified stress check for torsional effects. SHS. The details of these checks are as described below. l Cl 6. for this default setting. which results in torsion checks only being performed if the member is subject to torsional moments (i.T.Steel Design to Eurocode 3 [EN 1993-1-1:2005] l Clause 6. This is the primary condition that will need to be satisfied for members subject to torsion.T. All four of the clause checks mentioned earlier will be performed.2.0 The code also gives means to evaluate V in equations 6. The detailed output (i.2.2. Detailed Checks: This method will perform a full torsional analysis of the member.7(9) States that: For combined shear force and torsional moment.7C. TRACK 2) will indicate that torsion has been ignored for that particular member.Rd VEd / Vpl. II.. The method for working out the torsional resistance T .2. 6.28. 248 — STAAD. the plastic shear resistance accounting for torsional effects should be reduced from V pl. 6.7(9) is only performed for these section profiles.0 Where: T Rd is the design torsional resistance of the cross section. 6.Rd to V and the design shear force should satisfy: pl. European Codes . These pl.2.Rd equations.7(5) States that the yield criteria given in Cl.26 to 6.1(5) of EN 1993-1-1:2005 may be used for elastic verification. The program allows for two types of checks for members subject to torsion for EC3 design: I. You have the option to choose the method to be used for a specific member or group of members.e. Therefore.Pro evaluates the stresses due to the various actions on the cross section and applies this yield criterion. Setting the value of the TORSION parameter to three (3) will cause the program to ignore all torsional moments.e. This method will produce the output corresponding to Cl.2. The stress check will be performed using equation 6.7(5). will calculate the resultant stress (Von Mieses) at various points on the cross section.Ed τ Ed + − + 3 f y / γ M0 f y / γ M 0 f y / γ M0 f y / γ M 0 f y / γ M 0 ≤ 1 Where: σ σ τ x. This method is intended to be a simplified stress check for torsional effects per Cl.Ed σ z.Ed σ z.1 of EN 1993-1-1:2005 as given below: 2 2 2 σx . The program will consider the forces (including torsion) at various sections along the length of the member and for each section. See "Design Parameters" on page 264 for additional details. Basic stress check This method is used when the TORSION parameter is specified as one (1).Ed is the longitudinal stress is the transverse stress and Ed is the resultant shear stress.The details of setting the values to one (1) or two (2) and the corresponding checks performed are as described below. the program will perform the checks with a value of zero for the torsional moment. Any warping stresses that may develop due to the end conditions will be ignored for this option. The location and number of points checked for a cross section will depend on the cross section type and will be as described below. the program will perform the appropriate checks even if the member is not subject to torsional moments.Ed σx .Ed = σx + σbz + σby = Fx /Ax + Mz/Zz + My /Zy τEd = T/J · t + Vy ·Q/(Iz·t) + Vz·Q/(Iy *t) Where: T is the torsion at the particular section along the length of the member J is the torsion constant t is the thickness of the web/flange V is the shear force Q is the statical moment about the relevant axis I is the second moment of area about the relevant axis International Design Codes Manual — 249 . Note: Since transverse stresses are very small under normal loading conditions (excluding hydrostatic forces).2. 6. Note: If the TORSION parameter is set to 1 or 2. the term will be negligible and hence is taken as zero. In such cases. σx.Ed z. Steel Design to Eurocode 3 [EN 1993-1-1:2005] The stress check as per equation 6.7C. European Codes .1 is performed at various stress points of a cross section as shown in figures below: Shape Doubly symmetric wide flange profile Section Sketch Pipe profiles α = tan1 (M /M ) z y 250 — STAAD.Pro . 6.2. This method performs a detailed torsional analysis of a member depending on the torsion loading conditions and the support conditions at the member ends. This method is based on the SCI publication P057 and includes any warping stresses (direct warping stresses and International Design Codes Manual — 251 .7(5) in the detailed design output. Detailed stress check This method is used when the TORSION parameter is specified as two (2).Shape Tube profiles Section Sketch Channel profiles The resultant ratio will be reported under Cl. P057] Where: φ’ and φ’’’ are the first and third derivates of twist (φ ).Rd = τmax · J / t 252 — STAAD. Venant’s) moment (T The warping torsional moment(T Therefore. respectively. The loading/end conditions for a member are specified by the use of the CMT design parameter (See "Design Parameters" on page 264 for parameter values and descriptions).Ed ) and ) TEd = Tt. All the equations used to evaluate the torsional moments and associated stresses are as given in Appendix B of P057. These are evaluated from the equations in Annex B of P057 and are based the specified CMT parameter. the NCCI does not give the eqn. and depend on the end conditions and loading. This implementation considers seven different cases of loading and end conditions as given in publication P057 – Section 6. allowable shear stress = (fy/√3)/ Γm0 For open sections (I & channel): Tt. the torsion at any section T Ed is resolved into two components.Steel Design to Eurocode 3 [EN 1993-1-1:2005] warping shear stresses) depending on the end conditions of the member.2.7(1) – Torsional resistance of the section.Rd For closed sections: Tt. European Codes . Note: Although the equation given the NCCI document SN007b-EN-EU can be used to evaluate T . The pure torsion resistance (T ) and the t. Therefore.Ed The pure torsional (St. In general.Rd = 2 · Ac · t · τmax Where: A is the area enclosed by the mean perimeter c t is the max thickness τ max is the max.7C. The resultant stresses are evaluated at various sections along the length of the member and the following checks will be performed: Clause 6. viz. w. Annex B wrd of P057 is used.Pro . to evaluate φ’’’.Ed + Tw.Ed = GJφ’ = EHφ’’’ [Ref SCI pub. t. The torsional resistance of the section is also considered as the sum of the pure torsion resistance and the warping torsion resistance.Rd warping torsional resistance (T ) are evaluated as: w. 25 f y / ( 3 / γ M0 ) − τ w .2.Rd pl.6.Rd = (fy / Γm0 )· t · b2 / 6 Where: b is the width of the section t is the thickness of the flange for I. the design shear resistance will be reduced to V .Ed / Tw.T.6 for EC3 and the plastic shear resistance (in the absence of torsion) is evaluated as: Vpl.25 f y / ( 3 / γ M0 ) Vpl.Pro checks for shear resistance of a section based on Cl. For Structural Hollow Sections: Vpl. Rd = 1 − τ .Rd i.Rd ≤ 1 TEd / TRd ≤ 1 Clause 6. Rd ii. T .7(9) – Plastic shear resistance due to torsion STAAD.Ed (f y / Vpl.Ed (f y / Vpl. T .T.2. T .Rd ≤ 1 Tw. For I or H Sections: Vpl. along with the shear force. Tw.Ed / Tt. For Channel Sections: Vpl. Rd = 1 − τ .Ed 1. minimum of flange or web thickness channel sections The check according to Cl 6.sections.25 f y / ( 3 / γ M0 ) − τ w .Ed 1.2.Ed 1. where V is evaluated as follows: pl. Rd 3 ) / γ M0 Where International Design Codes Manual — 253 . Rd = 1 − τ . 6.2.6 (3) for the various sections v When torsion is present.Where: J is the torsion const t is the max thickness.7(1) will then be performed to ensure that the following conditions are satisfied: Tt. Rd 3 ) / γ M0 iii. Rd = Av f y / γ M0 ( 3 ) Where: A is as pre Cl. t. Venant’s) torsion and is the shear stress due to warping torsion. A is the area delimited by the mean perimeter and t is the thickness of the cross section τ w. Channel] sections: For I and H sections.Ed The various shear stresses due to torsion τ i. For Open sections [I. European Codes . thus.Steel Design to Eurocode 3 [EN 1993-1-1:2005] τ τ t. are not subject to warping stresses: The warping shear stress is evaluated as: τw. w.Ed The stress due to pure torsion is evaluated as: τt.Ed = G·t·φ’ [Ref SCI pub. since warping is ignored ii.Pro . This will be taken from section 6 and Annex B of P057.Ed is the shear stress due to direct (St. the web will not be subject to warping stresses and therefore warping shear can be ignored (τ =0).Ed are evaluated as follows: The shear stresses due to warping can be ignored as they will be insignificant and hence: τt. For Closed sections: and τ w. in which case the flange thickness is used.Ed w. P057] Where: G is the shear modulus φ’ is a function depending on the end condition and loading(T). Note: Although the maximum stress is at the thickest section of the profile.Ed = 0.Ed = TEd /(2·Ac·t) [Ref NCCI Sn007b-EN-EU] Where: T Ed c is the applied torsion. For channel sections that are free to warp at the supports and.Ed = E·Sw·φ’’’ / t [Ref SCI pub. H.7C. P057] 254 — STAAD. the program uses the web thickness for this clause (since the shear capacity is based on the web area) unless the load is parallel to the flanges. 7(9). S is the warping statistical moment and w φ’ is a function depending on the end condition and loading(T). Check for yield (capacity checks) is then done according to Eqn 6.Pro uses the yield criterion given in EC-3.2. Myt = φ·Mz (see Appendix B of P057 to evaluate φ) Shear stresses due to torsion and/or warping is evaluated as described above for Clause 6.Ed σx .7(5) – Check for elastic verification of yield Eurocode 3 gives yield criterion as per eqn.Ed σ z. Clause 6. the stresses are evaluated as follows: Direct bending stress (major axis): σbz = Mz / Zz Direct bending stress (minor axis): σby = My / Zy Direct stress due to warping: σw = E·W ns· φ’’ Direct stress due to twist (min.2.1 and STAAD. The angle of twist caused by torsion is amplified by the bending moments and will induce additional warping moments and torsional shears.Ed τ Ed + − + 3 f y / γ M0 f y / γ M 0 f y / γ M0 f y / γ M 0 f y / γ M 0 ≤ 1 International Design Codes Manual — 255 . Account must also be taken of the additional minor axis moments produced by the major axis moments acting through the torsional deformations. This will be taken from section 6 and Annex B of P057.Ed σ z. For members subject to bending and torsion. t is the thickness of the element. axis): σbyt = Myt / Zy Direct stress due to axial load (if any): σc = P/ A Where: M is the major axis moment & My is the minor axis moment. & Table 6) W ns is the normalized warping function. some degree of interaction occurs between the two effects. z φ’’ is the differential function based on twist (ref P057 Annex B. including the amplifications mentioned earlier.Where: E is the elastic modulus. 6.1 of EN 1993-1-1:2005. When a member is subject to combined bending and torsion. as described for the Basic Stress Check (TORSION = 1): 2 2 2 σx . Rk / γ M1 ≤1 Where: C is the equivalent uniform moment factor for bending about the z-z axis.ED χ LTM y .2 of EN LT 1993-1-1.Ed T w . Note: For all of the above checks the effective length of the member to be used for torsion can be set by using the EFT design parameter.Rk / γ M1 1 1 − M y .Ed and z-z axis. 7C. from EN 1993-1-1.Rk cross-section about it y-y and z-z axis.Rk z.Ed w.Rk / γ M 1 M z.7C. respectively.Rk χ is the reduction factor for lateral torsional buckling according to 6. k w = 0.Ed z. M T T y.cr M and M are the design values of the maximum moment about the y-y y. Members subject to combined bending and torsion will be checked to satisfy: M y .RK / γ M1 + k wk zwk αT w . mz according to EN 1993-1-1 Table B. Table 6.5 Members Subject to Combined Forces 256 — STAAD. w. Note that this interaction equation does not include the effects of any axial load.3. is the characteristic value of the warping torsional resistance moment. Warning: At present.2T w .Ed T w . So at present is advisable not to allow for torsion in a member with large axial load.7 − k zw = 1 − kα = 0. M and M are the characteristic values of the resistance moment of the y.Ed M z. respectively.cr is the elastic critical lateral-torsional buckling moment about the y-y axis.5. SCI advises that no significant work has been published for this case and work is still ongoing.Ed / M y . European Codes .Ed M z.RK / γ M1 + C MZM z.3. is the design value of the warping torsional moment.7.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Clause EC-3:6 App A – Check for combined Torsion and Lateral Torsional buckling The interaction check due to the combined effects of bending (including lateral torsional buckling) and torsion will be checked using Annex A of EN 1993-6: 2007.Pro . When specfied as 1.61 and 6.2.10 (3) of the code. EC3 requires checking cross-section resistance for local capacity and also checking the overall buckling capacity of the member.2. The program checks to ensure that both the interaction equations 6.2.1 of the code. the program evaluates the reduced yield strength as given in Cl 6.9 of the code. shear force.9. For class 4 sections. In case of a combined axial compressive load and bending moment. and a bending moment. The choice between using Annex A and Annex B will be based on the choice specified by a particular National Annex.44 are checked.9 checks for combined axial load and bending case. the interaction equation given by equation 6. 6. The EN 1993 design module in STAAD takes such a scenario into account and performs the necessary checks as per Cl. Shear.Rd moment capacity of the section. the program evaluates the reduced moment from the equations given in Cl.2. This is achieved by modifying the extreme compression fibre stress and calculating an effective applied moment for the section.62 of the code are satisfied. This reduced yield strength is then used to evaluate the reduced pl.Members subject to Bending and Axial Force When a member is subject to a combined axial load and a bending moment.3 of the code. kzy & kyz will be evaluated using Annex B of EN 1993-1-1 by default. The interaction factors kzz.2 of EN 1993-1-1.2. kyy. 6. The checks are done as per Cl. instead.9 of the code. In the case of members subject to axial load and biaxial bending. 2. 6. Members subject to Bending and Axial Compression The bending resistance of members could be reduced by the presence of a co-existent axial load.Pro (without National Annexes). you can override these values using the ALPHA and BETA design parameters (See "Design Parameters" on page 264). the program uses the more general equation 6.3 of the code. the program will use the values of the constants ‘α’ and ‘β’ as given in the code for the different sections types. uses Annex B. This is then checked against the lateral-torsional buckling resistance of the section. and 3 sections. However. if International Design Codes Manual — 257 . Hence for the EN 1993-1-1 code in STAAD. The reduction in the yield strength is done only when the applied shear force exceeds 50% of the design shear resistance V . the program evaluates a reduced moment capacity based on Cl. In the case of members subject to axial tension and bending.3. and Axial Force When a member is subject to a combined axial load. Generally. the member is checked per the rules in section 6. the program will consider the interaction equation 6. Members subject to Bending.6. Note: By default. 6. Note: The program uses the parameter ELB (See "Design Parameters" on page 264) to override the Cl. there is provision to take the stabilizing effect of the tension load into consideration.3.41 of the code. For Class 1. bending.7. Note: Laced or battened compression members are not dealt within the current version of EC3 (EN 1993) design module in STAAD. The stress design approach takes into account three categories of stresses: l Primary stresses: Stresses that are generated for the member to be in equilibrium with the direct imposed loads. 7C.5. settlement etc. & GM2 design parameters.10 of BS 5950-1:2000 is used in the current version of the EC3 design module. Cl.Pro: l LS1 – Plastic limit state: Deals with the condition when the capacity of the structure is exhausted by yielding of the material. Therefore. Secondary stresses: Those that are generated for internal compatibility or for compatibility at supports due to imposed loads or displacements (e. The following are considered by STAAD. GM1. the Eurocode 3 (EN 1993-1-1) design module of STAAD. shear and /or a combination of these conditions. European Codes . caused by loss of stability under compressive and/or shear membrane stresses. In these cases. Note: EN 1993-1-1:2005 does not specifically deal with single angle. and fatigue.Pro . The primary stresses considered are those generated due to axial loads.7C. EC3-6 deals with four types of ultimate limits states: plastic limit state. temperature.6 Design of Slender pipe sections to EN 1993-16 The design of Slender CHS sections is performed per EN 1993-1-6:2007 (hereafter. l The limit state verification is made based on the “Stress design” method described in EC3-6. See "Single Angel Sections" for ST and RA angle specifications. buckling limit state. LS3 – Buckling Limit state: Deals with the condition in which the structure (or shell) develops large displacements normal to the shell surface. the program uses Annex B to evaluate the interaction factors. EC3-6). double channels or Tee sections and does give a method to evaluate the slenderness of such members.. 4. the program uses the default safety factors from EN 1993-1-1. double angles. 258 — STAAD.g. l l Only the primary stresses are considered the program. cyclic capacity limit state.) Local stresses: Local stresses generated due to cyclic loading (or fatigue).Pro.Steel Design to Eurocode 3 [EN 1993-1-1:2005] used. If the National Annex itself gives a choice between Annex A and Annex B. EC3-6 does not specify additional or modified safety factors.Pro uses the methods specified in BS 5950-1:2000 to calculate the slenderness of these members. Note: You can change these values through the GM0. This section deals with the buckling strength of the member (LS3). i. The principle is to evaluate the membrane stresses due to the applied loads and then compare that to the buckling strength.Note: In the context of slender pipe section design for the Eurocode 3 module. the secondary and local stresses can be neglected since the loads and corresponding stresses dealt with in the design engine are largely direct and shear stresses.5 of the code. The local axis coordinate system for a CHS is defined as: circumferential around the circumference of the circular cross section (θ) meridional along the length of the member (x) normal perpendicular to the tangential plane formed by the circumferential and meridional directions (n) and the corresponding membrane stresses will follow the convention given below: Figure 7C. The pipe section is considered as an unstiffened cylindrical shell. which is evaluated giving due consideration for local buckling effects. Meridional Stresses: 1. Axial stress from bending International Design Codes Manual — 259 .Nomenclature for membrane and transverse stresses in Slender CHS sections Membrane stresses Transverse stresses Stress Design Stress checks are made based on the “Stress design” method as per Section 8. The membrane stresses are evaluated as given in Annex A of the code. Axial load Fx = 2·π·r·Px σx = -Fx /(2·π·r·t) 2.3 . t is the wall thickness of the cylinder Calculation of Axial Buckling Stress The buckling strength of A slender pipe section is evaluated using the method given in section 8. Shear Stress: 1. circumferential.4 . V V = π·r·Pθ.5.Pro .Steel Design to Eurocode 3 [EN 1993-1-1:2005] M = π·r2 ·Px. M Mt = 2π·r2 ·Pθ τ = Mt/(2π2 ·r2 ·t) Where: r is the radius of the middle surface of the shell wall.7C.max σx = ±M/(π2 ·r·t) ii. European Codes . and shear.Naming convention and coordinate system used for the buckling stress of a slender CSH section The axial buckling resistance is given by: σx. Transverse force. The design buckling stresses (buckling resistance) are calculated separately for axial. Shear from torsional moment. The circumferential stresses are ignored in STAAD.Rd = σx.Rk /γM1 260 — STAAD.2 ofEC3-6.Pro.max τmax = ±V/(π·r·t) 2. The naming convention and the coordinate axis used will be as given in the following diagram: Figure 7C. Once the relative slenderness is evaluated. See "Design Parameters" on page 264 The elastic critical buckling stress.2 of EC3-6.5· r/t International Design Codes Manual — 261 .5.Rk is the characteristic buckling strength given by: σx. χ is evaluated per Section x x 8.0 as in EN 1993-1-1.cr Where: σ x.2 of the code.7 1. the reduction factor is calculated as follows: χ = 1 when λ ≤ λ η 0 λ −λ0 χ = 1 − β λ −λ P 0 when λ < λ < λ 0 P χ= Where: α/λ2 when λ ≤ λ P λ is the plastic limit for slenderness given by: p λP = α 1−β The meridional buckling parameters the factors α and β are evaluated per section D.2(4) of EC3-6 and is determined as a function of the relative shell slenderness given by: λx = f yk σx .5· r/t ω > 0.Note: ΓM1 will have the same default value of 1. The details are as given below: The CHS section is classified based on the following criteria: CHS Length Classification Short Medium Long Criteria ω ≤ 1.1. Note: A ‘Normal’ fabrication quality will be assumed when evaluating the fabrication quality parameter as given in table D.2.cr is the elastic buckling critical stress. σ x.cr EC3-6. unless the fabrication quality is set using the FAB design parameter.7 < ω ≤ 0.Rk = Χx · fyk Where: χ is the meridional buckling reduction factor. σ and the factors α and β are evaluated per Annex D of x. 11. Calculation of Shear Buckling Stress The shear buckling resistance is given by: τxθ.Rd = τxθ. the program will also work out Cx based on equation D.1. p The CHS section is classified based on the following criteria: 262 — STAAD.Pro .Steel Design to Eurocode 3 [EN 1993-1-1:2005] Where: ω= l rt The elastic critical buckling critical stress is evaluated as: σx. and β parameters given in Annex D of EC3-6. there are two separate methods that can be used to evaluate the C factor: Eqns D. The reduction factor. European Codes . Initially the x program evaluates C based on the maximum from equations D.12 and D.5. However.Rk = Χθ· fyk Where: χ is the shear buckling reduction factor.cr Where: τ xθ. for long cylinders that satisfy the conditions in equation D.9/10 and Eqn D.2.605·E·Cx ·(t/r) Where: C is a factor dependant upon the CHS length classification as described in x section D.9/10.Rk /γM1 Note: γM1 will have the same default value of 1.9 x and D.7C.1 of EC-3-6.10.12 and then choose the minimum obtained from D.12. χ will be worked out as given in θ θ section 8.0 as in EN 1993-1-1.Rk is the characteristic buckling shear strength given by: τxθ.2(4) of En 1993-1-6 and is determined as a function of the relative shell slenderness given by: λθ = f yk τ xθ . is then evaluated as described for the axial buckling stress. based on θ the same λ . α. Note: For a long cylinder.Rk is the elastic buckling critical stress. χ .Rcr = 0. τ xθ. Rd kτ ≤1 Where: k and k are the interaction factors as given in section D.75ECτ 1 ω r Where: C is a factor dependant upon whether the CHS length classification as described τ in section D. Rcr = 0. an interaction check will be done according to equation 8.Ed ≤ τxθ.19 of the code as below: σx .Rd For a combined case of axial and shear stresses acting together.75 · χx kτ = 1.Ed τ xθ .1.4.7· r/t ω > 8.75 + 0.Ed σ x .25 · χτ International Design Codes Manual — 263 .CHS Length Classification Short Medium Long Where: ω= l rt Criteria ω ≤ 10 10 < ω ≤ 8.1. unless the fabrication quality is set using the FAB design parameter.Rd For shear stresses: τxθ.6 of EN 1993-1-6: x τ kx = 1. Note: A ‘Normal’ fabrication quality will be assumed when working out the fabrication quality parameter as given in table D.6 of the code.Ed ≤ σx. Buckling Strength Verification The buckling strength verification will be performed so as to satisfy the following conditions: For axial stresses: σx.Rd kx τ + xθ .1 of EC-3-6.25 + 0.7· r/t The elastic critical buckling critical stress is evaluated as: τxθ. 5 represents torque acting at the midspan of a symmetrically loaded member. Description 264 — STAAD.2-Steel Design Parameters EC3 EN Parameter Name CODE Default Value Must be specified as EN 1993-11:2005 to invoke design per Eurocode 3:2005 (EN 1993).7C. ALPHA 1.5 The ratio of the distance of the point torque (from the start of the member) to the length of the member. The default value of 0. the n setting must be compatible with the active “unit” specification. Some parameters are unit dependent and when altered. ALH 0. They are set to default values to begin with and may be altered to suite the particular structure. Values can range from 0 to 1.41 for combined bending and axial force checks. European Codes . Table 7C.1 of the Technical Reference Manual. Table 7C. you may have to change some or all of the parameter default values. Depending on the model being designed.48.0 Used to input a user defined value for the α factor in equation 6.6 Design Parameters Design parameters communicate specific design decisions to the program.4 lists all the relevant EC3 parameters together with description and default values.Steel Design to Eurocode 3 [EN 1993-1-1:2005] 7C. See section 5.Pro . Design Code to follow. C1 1. Check at location of maximum Mz along beam 2.0 check.3.3.2.2.Parameter Name BEAM Default Value 3 Description Parameter to control the number of sections to checked along the length of a beam: 1.2. 3.0 Used to input a user defined value for the β factor in equation 6.2 cr International Design Codes Manual — 265 .3.459 Corresponds to the C2 factor to be used to calculate Elastic critical moment M as per Clause 6. Check at every 1/13th point along the beam and report the maximum BETA 1.2 cr C2 0.2 cr C3 0 Corresponds to the C3 factor to be used to calculate Elastic critical moment M as per Clause 6.132 Corresponds to the C1 factor to be used to calculate Elastic critical moment M as per Clause 6. Check sections with end forces and forces at location of BEAM 1.41 for combined bending and axial force checks. 0 Indicates the level of End-Restraint. C2. cr Can take a value from 1 to 8. CMN 1.7 = One end free and other end fixed CMT 1 Used to indicate the loading and support condition for torsion (ref.5 for more information on its use. B of SCI-P-057. Refer to Table 7C.Pro .7C. Used to calculate the C1.0 = No fixity 0. Refer to Table 7C. 0 indicates that member will not be treated as a cantilever member 1 indicates that the member will be treated as a cantilever member CMM 1. Can take a value of 1-7.6 for more information 266 — STAAD.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Parameter Name CAN Default Value 0 Description Member will be considered as a cantilever type member for deflection checks. and C3 factors to be used in the M calculations. European Codes .0 Indicates type of loading and support conditions on member. 1.5 = Full fixity 0. SCI publication P-057). The values correspond to the various cases defined in section 6 and App. 0) Description "Deflection Length" / Max. See Note 1 below. denoting end point for calculation of "Deflection Length". 6.2. DJ1 Start Joint of member Joint No. TRACK 4. Uses Cl.Eqn.9 of EN 1993-11:2005 1..Parameter Name DFF Default Value 0 (Mandatory for deflection check.0 cm Maximum allowable depth for the member.1(7) . A value of 0 defaults to the member length. 6. DJ2 End Joint of member Joint No. 6.2. denoting starting point for calculation of "Deflection Length" .2 of EN 1993-1-1:2005 ELB 0 International Design Codes Manual — 267 . allowable local deflection See Note 1d below. DMIN 0 Minimum required depth for the member. Used to specify the method for combined axial load + bending checks 0. Uses Cl. See Note 1 below. EFT Member Length Effective length for torsion. DMAX 100. 3.3.25 Corresponds to the γ 1993-1-1:2005 m2 factor in EN 268 — STAAD.7C. FAB 3 Used to specify the fabrication class to be used to check for slender (Class 4) CHS/pipe sections (EN 1993-16:2007) 1.3 (NEN 6770): Rotation/bending capacity" on page 295 for additional description on this parameter.Pro .3 of NEN 6770: Section 1 1. Checks per Cl 12. Corresponds to the γ 1993-1-1:2005 m0 factor in EN GM1 1.2.1.2.3. Class A – Excellent 2.3 of NEN 6770: Section 2 See "Clause 12.0 Ultimate tensile strength of steel.2. European Codes .Steel Design to Eurocode 3 [EN 1993-1-1:2005] Parameter Name ESTIFF Default Value 0 Description (For use with the Dutch NA only) Method for checking columns forming part of (non)/buttressed framework: 0.1. Class C – Normal FU GM0 0 1. Checks per Cl 12.0 Corresponds to the γ 1993-1-1:2005 m1 factor in EN GM2 1. Class B – High 3.1. 0 Corresponds to the correction factor as per Table 6. Singapore. Circular Hollow Section 4. Single Channel 2. Program will calculate kc automatically if this parameter is set to 0. & Polish NAs. Note: For the British. Angle Section 5. International Design Codes Manual — 269 .Parameter Name GST Default Value 0 Description Used to specify the section type to be used for designing a “General Section” from the user table. I-Section 1. The available options and corresponding values are as below: 0. Rectangular Hollow Section 3.6 of EN 1993-1-1:2005. Tee Section Note: This parameter will be ignored if it has been assigned to any section other than a General Section. kc will be calculated as given in the NA by default. The member will be considered as the specified type with the user defined properties. KC 1. Used to calculate the effective length for slenderness and buckling calculations. as per Lyy.7C.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Parameter Name KY Default Value 1.Pro . Used for slenderness calculations.0 Description K factor in local y axis. European Codes . value of Lyy Leg length for Lvv (length about v-vaxis of single angle section). KZ 1. Slenderness ratio = (KZ)*(LZ)/(Rzz) LZ Member Length 270 — STAAD. See "Design Parameters" on page 74 LVV Max.0 K factor in local z axis. Used to calculate the effective length for slenderness and buckling calculations. LEG 0 Slenderness values for angles as determined from BS 5950-2000 Table 25. Slenderness ratio = (KY)*(LY)/(Ryy) Compression length in local z axis. LY Member Length Compression length in local y axis. See "European Codes . NA 0 Choice of National Annex to be used for EC3 design. MU 0 To be used with CMM values of 7 and 8. See Table 7C.National Annexes to Eurocode 3 [EN 1993-1-1:2005]" on page 283 for values allowed for this parameter.3. The available options and corresponding values are as below: 0.3 for rolled & built-up I-sections and Cl. Use default method based on section type (default) 1.2.g.2 2.. Use Cl.3 By default.3. the program will use Cl 6.2.2. (See "National Annex Documents" on page 237 for more information) International Design Codes Manual — 271 .3 to include other section types (e. 6.6. χ LT .3 by default for that particular section type.2.3.3. If. 6. See "European Codes .2 for all other sections. 6. the program will use Cl.3.6.3. the specified National Annex expands on Cl.Parameter Name MTH Default Value 0 Description Used to select the clause to be used to calculate the LTB reduction factor. Note: Currently valid only with the French & Belgian NAs.2.National Annexes to Eurocode 3 [EN 1993-11:2005]" on page 283 for additional details on NA documents. the UK NA). however.4. Use Cl.2. European Codes .0 = Rolled 1.Pro . RATIO 1 Permissible ratio of loading to capacity. NA.0 = Built-up 272 — STAAD.0 Description Net tension factor for tension capacity calculation.Steel Design to Eurocode 3 [EN 1993-1-1:2005] Parameter Name NSF Default Value 1. PLG 0 To be used to determine whether to include the additional interaction checks as per CL.0 Indicates if the section is rolled or built-up.7C. SBLT 0.20(2) and NA.20(3) of the Polish National Annex. Note: This parameter will be applicable only to the Polish NA PY Yield Strength The yield strength default value is set based on the default value of the SGR parameter. 0. Parameter Name SGR Default Value 0 Description Steel grade as in table 3.1 of EN 19931-1:2005 0.0 - indicates S 235 grade steel 1.0 - indicates S 275 grade steel 2.0 - indicates S 355 grade steel 3.0 - indicates S 420 grade steel 4.0 - indicates S 460 grade steel Note: As EN 1993-1-1:2005 does not provide a buckling curve in table 6.2 for grade S 450 steel (in Table 3.1 of EN 1993-1-1:2005), the program will use the same buckling curves as for grade S 460 when calculating the buckling resistance as per clause 6.3. STIFF Member Length or depth of beam, whichever is lesser TOM 0 Total torsion for design used for torsion checks. Can be used to override the total torsional moment to be used for member design. Distance between transverse stiffener plates, used to prevent web shear buckling. If not specified or if a value of 0 is provided, the program will assume the web is unstiffened. International Design Codes Manual — 273 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] Parameter Name TORSION Default Value 0 Description Method to be used for a specific member or group of members: 0. Perform basic torsion checks if member is subject to torsion. 1. Perform basic stress check (Ignore warping effects). 2. Perform detailed checks (including warping effects). 3. Ignore all torsion checks Note: For options 1 or 2, the program will perform the torsion related checked even if torsional moment is absent and will use a value of zero for the torsional moment. TRACK 0 Specify level of detail in output. 0. Summary of results only. 1. Summary with member capacities. 2. Detailed results. 4. Deflection check results only. UNF 1 Unsupported length as a fraction of the actual member length. UNL Member Length Unrestrained length of member used in calculating the lateral-torsional resistance moment of the member. 274 — STAAD.Pro Parameter Name ZG Default Value +Section Depth/2 Description Distance of transverse load from shear center. Used to calculate M . cr Note: For Tee sections, ZG will have a default value of (+Flange thickness/2) Notes: 1. CAN, DJ1, and DJ2 – Deflection a. When performing the deflection check, you can choose between two methods. The first method, defined by a value 0 for the CAN parameter, is based on the local displacement. Local displacement is described in Section 5.44 of the Technical Reference Manual. If the CAN parameter is set to 1, the check will be based on cantilever style deflection. Let (DX1, DY1, DZ1) represent the nodal displacements (in global axes) at the node defined by DJ1 (or in the absence of DJ1, the start node of the member). Similarly, (DX2, DY2, DZ2) represent the deflection values at DJ2 or the end node of the member. Compute Delta = SQRT((DX2 - DX1)2 + (DY2 - DY1)2 + (DZ2 - DZ1)2) Compute Length = distance between DJ1 & DJ2 or, between start node and end node, as the case may be. Then, if CAN is specified a value 1, dff = L/Delta Ratio due to deflection = DFF/dff b. If CAN = 0, deflection length is defined as the length that is used for calculation of local deflections within a member. It may be noted that for most cases the “Deflection Length” will be equal to the length of the member. However, in some situations, the “Deflection Length” may be different. A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. For example, refer to the figure below where a beam has been modeled using four joints and three members. The “Deflection Length” for all three members will be equal to the total length of the beam in this case. The parameters DJ1 and DJ2 should be used to model this situation. Thus, for all three members here, DJ1 should be 1 and DJ2 should be 4. International Design Codes Manual — 275 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] D = Maximum local deflection for members 1, 2, and 3. PARAMETERS DFF 300. ALL DJ1 1 ALL DJ2 4 ALL c. If DJ1 and DJ2 are not used, "Deflection Length" will default to the member length and local deflections will be measured from original member line. d. It is important to note that unless a DFF value is specified, STAAD will not perform a deflection check. This is in accordance with the fact that there is no default value for DFF (see Table 2B.1). e. The above parameters may be used in conjunction with other available parameters for steel design. 2. CMM Parameter The values of CMM for various loading and support conditions are as given below: Table 7C.3-Values for the CMM Parameter CMM Value 1 Loading and Support Conditions 2 3 4 276 — STAAD.Pro CMM Value 5 Loading and Support Conditions 6 7 varying end moments and uniform loading 8 varying end moments and central point load 3. Checking beam deflection With the TRACK parameter set to 4, the members included in a BEAM CHECK command will be checked for the local axis deflection rather than for the stress capacity using the current LOAD LIST. If both stress capacity and deflection checks are required, then 2 parameter blocks with code checks are required, one with a TRACK 4 command and one with a TRACK 0, 1 or 2, thus: LOAD LIST 1 TO 10 PARAMETER 1 CODE EN 1993 TRACK 2 ALL CODE CHECK MEMBER 1 *************************** LOAD LIST 100 TO 110 PARAMETER 2 TRACK 4 ALL DFF 300 MEMB 1 DJ1 1 MEMB 1 DJ2 4 MEMB 1 International Design Codes Manual — 277 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] CHECK CODE MEMB 1 Note: While both sets of code checks will be reported in the output file, only the last code check results are reported in the STAAD.Pro graphical interface. 4. CMT Parameter The values of CMM for various loading and support conditions are as given below: Table 7C.4-Loading and Support Conditions represented by CMT Parameter Values CMT Value 1 Description Diagram (Default) : Concentrated Torque at Ends. Ends Torsion fixed and Warping fixed Concentrated Torque along length of member. Ends Torsion fixed and Warping free Concentrated Torque along length of member. Ends Torsion fixed and Warping fixed Uniform Torque in member. Ends Torsion fixed and Warping free 2 3 4 5 Uniform Torque in member. Ends Torsion fixed and Warping fixed 6 Concentrated Torque in cantilever. End Torsion fixed and Warping fixed 278 — STAAD.Pro CMT Value 7 Description Diagram Uniform Torque in cantilever. End Torsion fixed and Warping fixed Note: For CMT = 2 and CMT = 3, you have the option of specifying the distance at which the concentrated torque acts, measured from the start of the member. This can be done by using the ALH design parameter. The ALH parameter indicates the ratio of the distance of the point torque (from the start of the member) to the length of the member. This parameter will have a default value of 0.5 (i.e., the torque acts at the center of the span) and will accept values ranging from 0 to 1. Note: The GB1 parameter that is being used for compression checks in builds preceding this release (STAAD.Pro 2007 build 06) has been removed as this parameter is no longer required in EN 1993-1-1:2005. Hence any legacy files that use GB1 parameter will indicate an error message and you will be required to substitute GB1 with GM1, in accordance with EN 1993-1-1:2005. 7C.7 Code Checking The purpose of code checking is to ascertain whether the provided section properties of the members are adequate. The adequacy is checked as per EN 1993-1-1:2005 and a corresponding National Annex (if specified). Code checking is done using the forces and moments at specific sections of the members. When code checking is selected, the program calculates and prints whether the members have passed or failed the checks; the critical condition; the value of the ratio of the critical condition (overstressed for value more than 1.0 or any other specified RATIO value); the governing load case, and the location (distance from the start of the member of forces in the member where the critical condition occurs). Code checking can be done with any type of steel section listed in Section 2B.4 or any of the user defined sections as described in Section 1.7.3 of the Technical Reference Manual, with the exception of ISECTION. ISECTION has been currently excluded since the option of Tapered section design is currently not supported in the EC3 module. The EC3 (EN 1993) design module does not consider these sections or PRISMATIC sections in its design process. Note: Checks for slender sections to EN 1993-1-1 are limited to I-SECTIONS, TEE, SINGLE CHANNEL, SINGLE ANGLE and CIRCULAR & RECTANGULAR HOLLOW SECTIONS. International Design Codes Manual — 279 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] Code checking for GENERAL sections can be also done using the EN1993 module. The program will design GENERAL sections as I sections by default. However, you are given the option to choose a ‘section type’ to be considered while designing the member. Refer to the description of the GST design parameter in Section 7C.6 for details. 7C.8 Member Selection STAAD is capable of performing design operations on specified members. Once an analysis has been performed, the program can select the most economical section, i.e., the lightest section, which fulfills the code requirements for the specified member. The section selected will be of the same type section as originally designated for the member being designed. Member selection can also be constrained by the parameters DMAX and DMIN, which limits the maximum and minimum depth of the members. Member selection can be performed with all the types of steel sections with the same limitations as defined in Section 7C.7. Selection of members, whose properties are originally input from a user created table, will be limited to sections in the user table. Member selection cannot be performed on members whose section properties are input as prismatic or as the limitations specified in Section 7C.7. 7C.9 Tabulated Results of Steel Design For code checking or member selection, the program produces the results in a tabulated fashion. The items in the output table are explained as follows: MEMBER refers to the member number for which the design is performed. TABLE refers to steel section name, which has been checked against the steel code or has been selected. RESULTS prints whether the member has PASSED or FAILED. If the RESULT is FAIL, there will be an asterisk (*) mark on front of the member. CRITICAL COND refers to the clause in EN 1993-1-1:2005 code which governs the design. RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition. Normally a value of 1.0 or less will mean the member has passed. LOADING provides the load case number, which governed the design. FX, MY, and MZ provide the axial force, moment in local Y-axis and the moment in local z-axis respectively. Although STAAD does consider all the member forces and moments (except torsion) to perform design, only FX, MY and MZ are printed since they are the ones which are of interest, in most cases. 280 — STAAD.Pro LOCATION specifies the actual distance from the start of the member to the section where design forces govern. Note: For a TRACK 2 output, the module will also report all the relevant clause checks that have been performed and will also indicate the critical ratio and the load case that caused the critical ratio as well as the corresponding forces that were used for the respective checks. A TRACK 2 output will also include the various design data used for the calculations such as the section modulii, section class, section capacity etc. If an NA parameter (other than 0) has been specified and if the particular National Annex requires additional checks outside those specified in EN 1993-1-1:2005 (e.g., The Dutch National Annex), the respective NA clauses and any associated code clauses will be listed along with the critical ratios and the forces that were used for these clause checks. 7C.9.1 Example of a TRACK 2 output Documentation notes appear in red. Note: The results and output follow the axis convention as described in Section 7C.1.3 STAAD.PRO CODE CHECKING - BS EN 1993- Code title & version 1-1:2005 ******************************************** NATIONAL ANNEX - NA to BS EN National Annex used, if any 1993-1-1:2005 PROGRAM CODE REVISION V1.9 BS_EC3_2005/1 ALL UNITS ARE - KN MEMBER TABLE Design engine version METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST 6.3.3-662 HD320X127 0.045 (EUROPEAN SECTIONS) Member number, section profile & table PASS EC- Design status, critical code clause, & critical ratio 1 25.00 C 5.00 Section forces & critical section location -10.00 0.00 ======================================================================= MATERIAL DATA Grade of steel = USER Modulus of elasticity = 205 kN/mm2 Design Strength (py) = 275 N/mm2 SECTION PROPERTIES (units - cm) Member Length = 500.00 Gross Area = 161.30 Net Area = 161.30 "z-axis" here refers to bending about Z-Z (when Y is Up), where as EC3 uses the Y-Y axis convention. z-axis 30820.004 y-axis 9239.001 Moment of inertia : International Design Codes Manual — 281 7C. European Codes - Steel Design to Eurocode 3 [EN 1993-1-1:2005] Plastic modulus Elastic modulus Shear Area Radius of gyration Effective Length DESIGN DATA (units - kN,m) Section Class : 2149.000 : 1926.250 : 81.998 : 13.823 : 500.000 EUROCODE NO.3 /2005 : CLASS 1 4435.75 0.006 1.00 z-axis 36.2 4078.2 4435.8 591.0 591.0 1301.9 MB = 939.100 615.933 51.728 7.568 500.000 Section class as per Table 5.2 y Squash Load : Axial force/Squash load : GM0 : 1.00 GM1 : 1.10 Slenderness ratio (KL/r) Compression Capacity Tension Capacity Moment Capacity Reduced Moment Capacity Shear Capacity : : : : : : Max. cross section capacity (A · f /GM0 GM2 : Partial safety factors used y-axis 66.1 3045.5 4435.8 258.3 258.3 821.3 BUCKLING CALCULATIONS (units - kN,m) Lateral Torsional Buckling Moment co- 591.0 Factor C1 used in M calculations and End restraint factor (corresponds to the CMN design cr parameters efficients C1 & K : C1 =2.578 K =1.0, Effective Length= 5.000 Elastic Critical Moment for LTB, Mcr = 1541.5 Critical Load For Torsional Buckling, NcrT = 13898.0 Critical Load For Torsional-Flexural Buckling, NcrTF = 13898.0 ALL UNITS ARE - KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= CRITICAL LOADS FOR EACH CLAUSE CHECK (units- kN,m): CLAUSE RATIO LOAD Max. ratio, loadcase, & section forces for each clause check FX VY VZ MZ MY EC-6.3.1.1 0.008 1 25.0 0.0 0.0 -10.0 5.0 EC-6.2.9.1 0.020 1 25.0 0.0 0.0 -10.0 5.0 EC-6.3.3-661 0.035 1 25.0 0.0 0.0 -10.0 5.0 EC-6.3.3-662 0.045 1 25.0 0.0 0.0 -10.0 5.0 EC-6.3.2 LTB 0.017 1 25.0 0.0 0.0 -10.0 5.0 Torsion and deflections have not been considered in the design. _________________________ ************** END OF TABULATED RESULT OF DESIGN ************** 282 — STAAD.Pro 7D. European Codes - National Annexes to Eurocode 3 [EN 1993-1-1:2005] A number of countries that have signed up to the replace their current steel design standards with the Eurocode, EN 1993-1-1:2005, known commonly as Eurocode 3, have published their National Annex documents. These documents make small changes to the base document and STAAD.Pro has been updated to incorporate some of these National Annex documents. The parameter NA sets the default material gamma factors and any additional changes outlined in the country specific National Annex such as specific equations or methods. These are described for each National Annex document in the following sections. The output file printout has been updated to indicate which National Annex (if any) has been used in a code check / select process (For all TRACK settings). Design of members per EC3 National Annexes requires the STAAD Euro Design Codes SELECT Code Pack. 7D.1 General Format The format of the EN 1993-1-1:2005 National Annex is as follows: CODE EN 1993 NA f1 {Code parameters: See "Design Parameters" on page 264 } Where: f1 represents the number designation for a specific country's National Annex: Table 7D.1-Table 5B1.2(B) - Numerical Code for Eurocode National Annex NA Value 0 Country None — Uses the base EN 1993-1-1:2005 code, with no national annex changes or additions. The default values specified in En 1993-1-1:2005 will be used for the partial safety factors and various parameter values where applicable (default). United Kingdom (British NA) — Uses the BS EN 19931-1:2005 version of Eurocode 3 along with the UK National Annex. Netherlands (Dutch NA) — Uses the NEN EN 1993-11:2005 version of the code. The Dutch National Annex [NEN-EN 1993-1-1/NB] has been added in this module. Please note that the Dutch National requires additional checks as per NEN 6770 and NEN 6771 which will also be performed during design checks with this parameter value 1 2 International Design Codes Manual — 283 7D. European Codes - National Annexes to Eurocode 3 [EN 1993-1-1:2005] NA Value 3 Country Norway (Norwegian NA) — Uses the NS-EN 1993-11:2005 version of the code. The Norwegian National Annexe [ NS-EN 1993-1-1:2005/Na 2008] has been added to this implementation. France (French NA) — Uses the Annexe Nationale a la NF EN 1993-1-1:2005 version of the code along with the French National Annex.. Finland (Finnish NA) - Uses the SFS EN 1993-1-1:2005 version of Eurocode 3 along with the Finnish National Annex. Poland (Polish NA) - Uses the PN EN 1993-1-1:2005 version of Eurocode 3 along with the Polish National Annex. Singapore (Singaporean NA) - Uses the SS EN 1993-11:2005 version of Eurocode 3 along with the Singaporean National Annex. Belgium (Belgian NA) - Uses the NBN EN 1993-1-1:2005 version of Eurocode 3 along with the Belgian National Annex. 4 5 6 7 8 7D.2 Specifying the design engine to use a national annex Use the following procedure to include additional check specified by a National Annex: 1. In the Modeling mode, select the Design | Steel tab. The Steel Design - Whole Structure dialog box opens. 2. In the Current Code drop-down menu, select EN 1993-1-1:2005. 3. Click Define Parameters…. The Design Parameters dialog box opens. 284 — STAAD.Pro 4. Select the NA parameter in the list box. 5. Select the option corresponding to the National Annex document you want to use . 6. Click Add. This will insert the following commands into the STAAD input file: CODE EN 1993-1-1:2005 NA 8 Refer to EC3 steel design for additional information on steel design per EC3. A design performed to the new Eurocode 3 National Annex is displayed in the output file (*.ANL) with the following header, in addition to the base EC3 output. International Design Codes Manual — 285 7D.1 Dutch National Annex to EC3 Adds values from the Dutch National Annex—titled NEN-EN 1993-1-1/NB—for use with Eurocode 3, or EN 1993-1-1:2005. The NA document makes small changes to the base document. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that require additional clauses from the Dutch National Annex (hereafter referred to as D-NA) are described in the following sections. Refer to the basic code (EC3) for a description of these clauses. The sections below refer to the corresponding clauses in the D-NA. Note: Clause 6.3.2.4 deals with a simplified assessment method for beams. STAAD.Pro only uses the more accurate method (6.3.2.2 and 6.3.2.3 in EC-3) and therefore this section is ignored. 7D.1.1 Axis Convention The local axis convention in the Dutch codes is: Y – major axis & Z – minor axis (as opposed to the convention followed in STAAD.Pro). Figure 7D.1 - Local axis convention used in the Dutch NA to EC-3 7D.1.2 Clause 6.1 – General The partial safety factors will use the following values: l l Resistance of cross-sections, γ M0 = 1.0 M1 Resistance of members to instability, γ = 1.0 International Design Codes Manual — 286 l Resistance of cross sections to tension, γ M2 = 1.25 The design function in STAAD.Pro sets these values as the default values for the D-NA (NA 3 is specified).. Note: You can change these values through the GM0, GM1, & GM2 design parameters. See "Design Parameters" on page 264 7D.1.3 Clause 6.2.8 – Bending and shear The D-NA requires the implementation of causes 11.3.1.1 and 11.3.1.3 of NEN 6770. Clause 11.3.1.1 (NEN 6770): Class 1 and Class 2 I-section profiles Class 1 and class 2 I section profiles must satisfy the interaction formulae given in tables 10 & 11 of NEN 6770. Table 10 Provides interaction checks for bending about the major axis (All necessary terms and formulae are described below): 1. If Vz;s;d ≤ 0.5·Vz;pl;d and Ns;d ≤ 0.5 · a1 · Npl;d , check equation 11.3.1 2. If Vz;s;d ≤ 0.5·Vz;pl;d and Ns;d > 0.5 · a1 · Npl;d , check equation 11.3.2 3. If Vz;s;d > 0.5·Vz;pl;d and Ns;d ≤ 0.5 · a2 · Nv;u;d , check equation 11.3-3 4. If Vz;s;d > 0.5·Vz;pl;d and Ns;d > 0.5 · a2 · Nv;u;d , check equation 11.3-4 Where: V V z;s;d = Actual Shear force in the section along Z- axis = Shear capacity of section along Z - axis y;d z;pl;d w =A ·f f y;d / √3 = yield stress 287 — STAAD.Pro Figure 7D.2 - Definition of A w Aw = A - 2 (bf - tw - 2r) tf N N s;d = Axial force in the section = Axial capacity of section = A · f y;d pl;d M M y;s;d = Bending moment about major axis = Plastic moment capacity of section = f y;d y;pl;d y;pl ·W y;pl W 1 = Plastic section modulus a = min( A-2bfx tf)/A , 0.5)- used in tables 10 & 11 a = see eqn 11.3-10- used in tables 10 & 11 2 M N v;y;ud = see eqn 11.3.12 ;v;u;d = see eqn 11.3-13 Table 11: Provides interaction formulae for bending about the minor axis 1. If Vy;s;d ≤ 0.25 · Vy;pl;d and Ns;d ≤ 1.0 · a1 · Npl;d check equation 11.3-5 2. If Vy;s;d ≤ 0.25 · Vy;pl;d and Ns;d > 1.0 · a1 · Npl;d check equation 11.3-6 3. IfVy;s;d > 0.25 · Vy;pl;d and Ns;d ≤ 1.0 · a1 · Nv;u;d check equation 11.3-7 4. If Vy;s;d > 0.25 · Vy;pl;d and Ns;d > 1.0 · a1 · Nv;u;d check equation 11.3-8 Where: V V y;s;d = Actual Shear force in the section along Y-axis = Shear capacity of section along Y-axis f y ;d 3 y;pl;d Vy ; pl ; d = 2btf International Design Codes Manual — 288 Mv;z;u;d = q · Mz;pld = q · fy;d · W pl;z;d W pl;z;d = plastic section modulus about minor axis) & q as per eqn 11.3-14 Nv;u;d = Npl;d – 2·(1 - q)·bf · tf · fy;d Clause 11.3.1.3 ( NEN 6770) : Class 1 and Class 2 Square and rectangular hollow sections This clause requires class 1 and class 2 square and rectangular tube profiles to satisfy the interaction equations in Table 13. 1. If Vz;s;d ≤ 0.25 · Vz;pl;d and Ns;d ≤ 0.5 · a3 · Npl;d check equation 11.3.22 2. If Vz;s;d ≤ 0.25 · Vz;pl;d and Ns;d > 0.5 · a3 · Npl;d check equation 11.3.23 3. If Vz;s;d > 0.25 · Vz;pl;d and Ns;d ≤ 0.5 · a4 · Nv;u;d check equation 11.3-24 4. If Vz;s;d > 0.25 · Vz;pl;d and Ns;d > 0.5 · a4 · Nv;u;d check equation 11.3-25 Where V V z;s;d = Actual Shear force in the section along Z-axis = Shear capacity of section along Z-axis z;pl;d b = breadth of section h = height of section A = area of section Vz ; pl ; d = Vz ; cl ; d = 3 f y ;d h A b +h 3 a = min{ (A - 2 · b · t)/A or 0.5} a = from equation 11.3.27 4 7D.1.4 Clause 6.2.10 – Bending shear and axial force Requires the implementation of clauses 11.3.1.1 to 11.3.1.3 and 11.3.2.1 to 11.3.2.3 of NEN 6770 and clause 11.3 of NEN 6771 Clause 11.3.1.1 (NEN 6770) and Clause 11.3.1.3 ( NEN 6770) See "Clause 6.2.8 – Bending and shear" on page 287 289 — STAAD.Pro Clause 11.3.1.2 (NEN 6770): Class 1 and class 2 circular hollow (CHS) profiles Class 1 and class 2 sections with circular hollow profiles should satisfy the interaction equations given in table 12. l l Check #1 – If Vz;s;d ≤ 0.25 Vz;pl;d check equation 11.3.17 Check #2 – If Vz;s;d > 0.25 Vz;pl;d check equation 11.3.18. See "Clause 6.2.8 – Bending and shear" on page 287 of this document for equations to derive Vz;s;d Vz;pl;d = Shear capacity of CHS sections Vpl ; d = 2 A f y ;d π 3 See equations 11.3-19 and 11.3-20 to evaluate Mv;y;u;d and N;v;u;d. To check for these conditions about the y axis, substitute the index ‘z’ in the above equations with ‘y’ (should be the same of CHS sections). Clause 11.3.2 ( NEN 6770) Section 11.3.2 in general deals with Biaxial bending with axial force and shear. The general condition to be satisfied in this case is given by equation 11.3-31 of NEN 6770 M y ;s ;d β 0 M N ;V ;y ;u ;d a1 M z;s ;d + β1 M N ;V ;z;u ;d a2 ≤1 Clause 11.3.2.1 : Class 1 and class2 I-sections with biaxial bending + shear + axial force The formula to evaluate M;N;v;y;u;d and M;N;v;z;u;d are to be taken from tables 14 and 15 of NEN 6770 respectively. Checks for table 14: 1. Check #1 – If Vz;s;d ≤ 0.5 Vz;pl;d and Ns;d ≤ 0.5 x a1 x Npl;d use equation 11.3.32 2. Check #2 – If Vz;s;d ≤ 0.5 Vz;pl;d and Ns;d > 0.5 x a1 x Npl;d use equation 11.3.33 3. Check #3 – If Vz;s;d > 0.5 Vz;pl;d and Ns;d ≤ 0.5 x a2 x Nv;u;d use equation 11.3-34 4. Check #4 – If Vz;s;d > 0.5 Vz;pl;d and Ns;d > 0.5 x a2 x Nv;u;d use equation 11.3-35 See "Clause 6.2.8 – Bending and shear" on page 287 for equations to evaluate Vz;s;d, My;pl;d, Npl;d, Mv;y;ud, N;v;u;d, a1 ,a2 and Vz;pl;d. Checks for table 15: International Design Codes Manual — 290 ud.pl.d.44 & 11.d use equation 11. See table 16 for α1.3.d.3 : Class 1 and class2 Rectangular and square hollow tubes The formula to evaluate M.pl.25 Vy.pl.3.3-50 4.z. β0 and β1 use in tables 14 and 15.pl.s.3 ( NEN 6771) In general.d and Ns.d use equation 11.pl.d > 0.d and M.2. 1.u.d ≤ 1.2 above) are to be taken from table 19 of NEN 6770. Clause 11.0 x a1 x Npl.pl.d use in equations 11.3.N.N.5 x a3 x Npl.d. a1 .u.pl. My.3.s.1.3.y.36 2. Check #1 – If Vz.d ≤ 1.2 above) are to be taken from table 17 of NEN 6770.25 Vy.0 x a1 x Nv.z.d.d (to be used in equation 11-3-31. 1.3.d and Ns.2.2. β1 and β2 in this case refer to table 18 of NEN 6770. this section deals with Biaxial bending with axial force and shear for class 3 and class 4 sections.d and Ns.s.s.pl. 291 — STAAD.s.5 x a3 x Npl.3. Mv. Check #3 – If Vy.2.d and Ns.ud. See "Clause 6. α2.pl.25 Vz. Check #1 – If Vz. β1 and β2 in this case refer to table 20 of NEN 6770.37 3.d.pl.3.d.2 : Class 1 and Class 2 Circular hollow tubes The formula to evaluate M.pl.v.u. Npl.v.y.d > 1.d.45.u.0 x a1 x Npl.8 – Bending and shear" on page 287 for equations to evaluate Vy.u.d use equation 11.s.d (to be used in equation 11-3-31.0 x a1 x Nv.5 x a4 x Nv. Check #1 – If Vy. Check #2 – If Vz. Check #2 – If Vy.25 Vz.49 3.8 – Bending and shear" on page 287 for equations to evaluate Vz.d > 0. My.d use equation 11.d > 0.2. Mz.s.d use equation 11. Npl.d ≤ 0.u.d. α2. Check #4 – If Vy.s.d ≤ 0.25 Vy.25 Vz.3.v.y. α1.3-39 See "Clause 6.u. see description of clause 11.d ≤ 0.d and Ns.pl.d ≤ 0.d check equation 11. Check #2 – If Vz.d and Ns. Check #4 – If Vz. To check for these conditions about the y axis.d.pl. For values to be used for α1.N. Clause 11.u.25 Vz.3. a3.pl.d use equation 11.v.45.d and Ns.s.d > 0.v.25 Vy.3-51 See "Clause 6.d and Ns. Check #3 – If Vz. N.s.Pro . N.d ≤ 0. a4 and Vz.pl.d > 1.d to be used in the above equations.v.d > 0.d.pl.d use equation 11.d.d ≤ 0.pl. Clause 11. For values to be used for α1.s.8 – Bending and shear" on page 287 for equations to evaluate Vz.d check equation 11.25 Vz.d check equation 11. see description of clause 11.u.d ≤ 0.3-48 2. substitute the index ‘z’ in the above equations with ‘y’.a2 and Vy. Mv.z.d > 0.d and M.3-38 4.3.d > 0.5 x a4 x Nv.N.u.44 2.25 Vz. and Npl. 2 of NEN 6771 to be applied.d is the moment capacity about the Y axis for the effective section.u. the following cases are checked: 1.d FE .Check for class 3 sections: For class 3 sections use the method in section 11.u .s.3.u .3 of NEN 6771.s. u .d ≤ 1 check equation 11.y.d1 − − 1 Vz.f.s .2. Working out the effective section properties for slender sections has already been done in STAAD.2-13 (given below): M y .d > 1 and M.d International Design Codes Manual — 292 . If M.s .d = A·fy.d − M N .θ Where: Nc. For an I section.13.2.u . which in turns requires the checks as per clauses 12.y.eff) 2.2.d / MN. et 2 3 f y .section profiles and tubular sections.u .d ≤1 check equation 11.4. For class 3 sections the methods and equations discussed above can be used with the ‘plastic section modulus’ being substituted with the ‘elastic modulus’.s.u.y.d M N .f. MN.1.y.d 2 2Vz.y.0.3 NEN 6770.s. 12. Vz .2.1.u.2.u.u.3 – Buckling resistance of members The D-NA introduces a new clause 6. = ( fy·W.f.1.y .5 Clause 6.d ≤ 1 Where V V z.d ≤1 7D.d + M N .3.2. Check for class 4 sections: Class 4 sections can be treated as class 3 sections if the effective section properties are used as given in clause 10.ef = effective web area as given in section 10.Pro.d /Vz. If M.u.2-7 ( given below) Vz.1.s.y.4. Clause 12.f .y . re = N c .d / M.d z.2.u .2 (NEN 6771) This clause in NEN 6771 determines the relative torsional slenderness and is given as: λ θ.y. For I.4.y . d = A w.d 3 Where Aw.u.d / MN.d is the shear for in the Z direction is the shear capacity in the Z direction for ultimate limit state.f .2 and 12.f. tk Clause 12. Note: STAAD.3.1.3 and 12.2 of NEN 6770 and clause 12.tk Where Nc. The effective length factors may be used to accommodate this requirement.5.d A = area of section f y. STAAD.3 – Slenderness for flexural buckling The Dutch NA requires the implementation of clause 12.3 (NEN 6770) This clause gives the equations to evaluate the effective lengths for various support conditions.6 Clause 6. specifically.d = A·fy.2 (NEN 6771) This clause works out the relative torsional-flexural buckling slenderness for compression members.2 (NEN 6771) Buckling lengths of rotationally restrained bars with intermediate spring supports. The relative torsional-flexural buckling slenderness is given as: λ tk .1.d FE .Pro .3.1.u .1. 7D.1.d = yield stress is the Euler torsional buckling strength F E. re = N c .1.1.θ = the yield stress is the Euler-torsion formula F This value of slenderness is to be used to calculate the modification factors used in section 6.Pro does not allow for these end conditions.A = area of section f y.u.1. Clause 12.1. 293 — STAAD.d E.3.4. Clause 12.1.3 of EC-3.1.Pro uses the effective length factor ‘K’ which allows the user to set/modify the effective lengths for a member.3 of NEN 6771. 2 and 12. Clause 12.1.1.2 (NEN 6770) This clause gives methods to evaluate the buckling length of lattice sections.1.3.1. HEB & HEM sections and pipe sections do not need to be checked for torsional instability.1. 7D.5.7 Clause 6.3 of NEN 6770 Clause 12.1. Clause 12.1.Clause 12.3 of NEN 6771.1. We do not deal with latticed section in the current version of STAAD. HEA.d C.4 – Slenderness for torsional and torsional-flexural buckling The D-NA requires the implementation of clauses 12.1.u .2 (NEN 6771) This clause gives the condition to check for torsion instability. for I sections that have rigid supports that is not along the axis of the section and any other sections will need to be checked as per clause 12.u. The condition being: N c .1.Pro is adequate to cater for adjusting the effective lengths as necessary.1.2 of NEN 6771.d ≤1 Where: N N c.d ω θN c .s. they should be done according to 12.d fu . However.3. y σ θ . If torsional checks need to be performed.3 (NEN 6770): Torsional flexural stability Doubly symmetric sections need not be checked for torsional flexural instability.3 (NEN 6771) This clause gives the condition to check for torsional flexural instability.1.2 (NEN 6770): Torsional stability IPE. Clause 12.3 (NEN 6771) This clause again deals with working out the effective lengths of prismatic and non-prismatic rods.Pro.d ωθ = Clause 12. Again.s . In any case the buckling length can be adjusted using the ‘K’ factor. The condition being: International Design Codes Manual — 294 .d = the applied axial load = the axial capacity = A · f .1. the ‘K’ factor in the current implementation of STAAD. 5.u.2 and 6.3.kc)[1 .3.d ωt .2 – Lateral torsional buckling curves general The D-NA states that the values for the imperfection factor.3 ( EC-3) checks. is given by F = 1 – 0.2 above. f. 3.3.57 of EC-3) Β = 0.2.d and N c. 7D.Pro conservatively uses a value of f = 1.Pro.3 of NEN 6770.2.2.2.d ≤1 Where: N c.57 of EC-3) These are the default values used by the program. 295 — STAAD. See "Design Parameters" on page 264 The current implementation of STAAD.9 Clause 6.2.Pro uses the method in Annex B.2.3.s.3.1. The reduction factor.3.3 (NEN 6770): Rotation/bending capacity The Dutch NA also requires additional checks as per clause 12.56 of EC-3 are to be obtained from sTable 6. kyz.Pro .0. αLT.d as in clause 12.6. The buckling curves shall be selected as per Table 6.2x (λLT -0. Clause 12.8)2 ].4 (used in equation 6.1.1.33 – Uniform members in bending and axial compression The D-NA recommends the use of the method in Annex B of EC-3 to determine the values of kyy. 2.3 – Lateral torsional buckling curves for rolled sections or equivalent welded sections The D-NA states that: 1.k N c .3 – Lateral torsional buckling curves Clause 6.1. to be used in equation 6.s .1. kc is a correction factor for moment distribution determined from Table 6.u .75 (used in equation 6. Clause 6.5(1 . This value can be specified or calculated by the program using the KC parameter. kzy and kzz to be used in 6. The values for the: l l Imperfection factor αLT0 = 0.8 Clauses 6.3.3 of EC-3. These are the values used by STAAD. 7D. STAAD.N c . Selecting this value will internally perform the checks as per section 1 of clause 12.3 Column is not part of a buttressed framework.3.d pl.s.15 and the steel grade is S235 or S 275 then N c .1-Framework parameter ESTIFF values for the Dutch NA ESTIFF value Description (default) Column part of a buttressed framework.d N p .d ≥ 0.3.2.2.s.d < 0.d/ Npl.d N p .s .s.d + λy 100 ≤1 Where: N c.s .s.s.1.d/ Npl.d = the axial load in the section International Design Codes Manual — 296 .3 0 1 These checks are described below: 1.d ≥ 0. Selecting this value will internally perform the checks as per section 2 of clause 12.d + λy 120 ≤1 Where: N N c.d is the axial load in the section = Axial capacity of section = A·f y.1.d/ Npl.The checks given in this clause deals with additional checks for columns that form part of a buttressed or non-butressed framework. The program uses the ESTIFF parameter with two different values to identify the framework type: Table 7D.15 and the steel grade is S355 then N c . no additional checks are required If Nc.15. For columns in buttressed frameworks the buckling length is to be taken based on either l l the system length or the distance between adjacent lateral supports The following conditions should also be satisfied: If Nc.d λ = Slenderness of the section about the major axis ( Y-axis) y If Nc. d ≥ 0.15 and the steel grade is S355 then N c .d N p .d/ Npl.d pl.d + λy 80 ≤1 297 — STAAD.s .N pl.15. For columns that are not part of buttressed frameworks the following additional checks need to be done: If Nc.d λ = Slenderness of the section about the major axis ( Y-axis) y If Nc.s.d < 0.s.s. no additional checks are required If Nc.s.15 and the steel grade is S235 or S 275 then N c .d = the axial load in the section and = Axial capacity of section = A·f y.d λ = Slenderness of the section about the major axis ( Y-axis) y 2.d/ Npl.d = Axial capacity of section = A·f y.s .Pro .d + λy 100 ≤1 Where: N N c.d/ Npl.d ≥ 0.d N p . e.γ M0 = 1.25 Resistance of cross sections to tension .γ M2 The design function in STAAD. EN 1993 provides default values for M0 M1 M2 these factors. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that require additional clauses from the Norwegian National Annex are: 7D. The partial safety factors will use the following values: l l l Resistance of cross-sections .1 of the code.05 M1 Resistance of members to instability .. The sections below refer to the corresponding clauses in the Norwegian -NA. International Design Codes Manual — 298 . These factors are γ .1 Clause 6. Refer to the basic code (EC3) for a description of these clauses. See "Design Parameters" on page 264 Note: If any of these parameters are specified as 0.Pro sets these values as the default values for the NorwegianNA (NA 3 is specified).Pro will ignore the user specified value (i. and γ .γ = 1. However. 0) and use the default values as given above. any National Annex is allowed to override these default values. & GM2 design parameters.1. or EN 1993-1-1:2005.7D. γ .1(1) – General: Partial Safety Factors for buildings EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl. GM1.05 = 1.1 Norwegian National Annex to EC3 Adds values from the Norwegian National Annex—titled NA to BS EN 1993-1-1:2005—for use with Eurocode 3. STAAD. The NA document makes small changes to the base document. 6. Note: You can change these values through the GM0. However.0 M1 Resistance of members to instability.59 of BS EN 1993-1-1:2005 as 0.Pro does not use this clause for design per EC-3. or EN 1993-1-1:2005. STAAD. GM1.4(2)B – Modification factor ‘kfl’ The value of the modification factor kfl to be used in equation 6. Note: Refer to the basic code (EC3) for a description of these clauses.Pro will ignore the user specified value (i.1 of the code. 6. However. γ = 1. However.1 Resistance of cross sections to tension. γ ..1(1) – General: Partial Safety Factors for buildings EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl.60 of BS EN 1993-11.7D.4.for use with Eurocode 3. this clause is ignored for the UK National Annex.e. The sections below refer to the corresponding clauses in the UK-NA. Note: You can change these values through the GM0. See "Design Parameters" on page 264 Note: If any of these parameters are specified as 0. 0) and use the default values as given above. The following clauses are not implemented in STAAD. and γ .4(1) B – Slenderness for flexural buckling The UK NA specifies the value of λc0 for I.Pro does not use this clause for design per EC-3. γ M0 = 1.2.0 = 1.1. These factors are γ . STAAD. The NA document makes small changes to the base document.1 UK National Annex to EC3 Adds values from the UK National Annex . γ M2 The design function in STAAD.2.titled NA to BS EN 1993-1-1:2005 .Pro: Clause 6. STAAD.Pro sets these values as the default values for the UK-NA (NA 1 is specified). International Design Codes Manual — 299 . any National Annex is allowed to override these default values.1 Clause 6. & GM2 design parameters. The clauses/sections in EN 1993-1-1:2005 that have been dealt with in the UK National Annex (hereafter referred to as the UK-NA) are: 7D. H channel or box section to be used in equation 6.3. The partial safety factors will use the following values for the UK National Annex: l l l Resistance of cross-sections. Therefore. EN 1993 provides default values for M0 M1 M2 these factors. Clause 6.3. Therefore. this clause is ignored for the UK National Annex. 2 –Elastic critical moment and imperfection factors for LTB checks The UK-NA recommends the use of Table 6. The UK National Annex does not specify a particular method to calculate M .2 Clause 6. The NCCI provides values for C and C for the different cases as given in the tables 1 2 below: 300 — STAAD.Pro 2007 build 06) has been removed as this parameter is no longer required in EN 1993-1-1:2005.3. The calculation of the LTB reduction factor χ . Hence the calculation of M has been based on the following NCCI cr cr documents: SN003a-EN-EU – Elastic critical moment for Lateral torsional Buckling: This document provides a method to calculate ‘Mcr’ specifically for doubly symmetric sections only. Hence only doubly symmetric sections will be considered for this method in the proposed implementation.2. any legacy files that use GB1 parameter will indicate an error message and the user will need to substitute GB1 with GM1 in line with EN 1993-1-1:2005. 7D.Pro .4 of BS EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks. requires the calculation of the ‘Elastic LT Critical Buckling Moment’. Mcr.3 and 6. The equation to evaluate M is given in the NCCI as: cr M cr = C1 π EI s 2 k Iw + (kL ) 2 k w I s 2 (kL ) GI t π 2EI s 2 + (C2z s)2 − C2z s C and C are factors that depend on the end conditions and the loading conditions of the 1 2 member. Hence.1.Warning: The GB1 parameter that is being used for compression checks in builds preceding this release (STAAD. This NCCI considers three separate loading conditions: l l l Members with end moments Members with transverse loading Members with end moments and transverse loading. International Design Codes Manual — 301 . It does not however. Hence this implementation will use this method only for Tee-Sections. The first two loading conditions mentioned above and its variants can be dealt with by using the existing values of the CMM parameter (i. the NCCI provides graphs to evaluate the C1 and C2 coefficients. CMM 8: Member with varying end moments and central point load. In any case. the UK National Annex (nor the NCCI) does not provide equations to evaluate C1 and C2.Pro the user will have to use the new ‘C1’ & ‘C2’ parameters to input the required values for C1 & C2 to be used in calculating Mcr.Pro .. For values of 7 or 8 for the CMM parameter. Note: If the NA parameter has not been specified. Hence the appropriate values from this NCCI will be used for ‘C1’ and ‘C2’ coefficients depending on the value of CMM specified. provide a set of equations for these graphs. The default value of CMM is 1.The implementation of EC3 in STAAD. STAAD. the program will issue a warning if C1 and C2 have not been specified.Pro currently does not have a means to specify/identify a mono-symmetric built-up section. the actual LTB capacity will still be worked out as per BS 5950-1 as in the current EC3 implementation. Hence this implementation will introduce two new values for the CMM parameter viz. See "Design Parameters" on page 264 However. However the “end moments and transverse loading” condition cannot be currently specified in the design input. Hence for this implementation the elastic critical moment for ‘Tee-Sections’ will be worked out using the method in this NCCI. For these two conditions. CMM 7:Member with varying end moments and uniform loading. The user will also have the option to specify specific values for C and C using the C1 and C2 parameters in the 1 2 design input mode. Hence in STAAD.Pro accounts for the loading condition and the bending moment diagram through the CMM parameter. Note: Though this method could also be applicable to mono-symmetric built-up sections. which considers the member as a pin ended member with UDL along its span. 1 to 6). SN030a-EN-EU – Mono-symmetrical uniform members under bending and axial compression: This document provides a method to evaluate the elastic critical moment (Mcr) for uniform mono symmetric sections that are symmetric about the weak axis.e. the program obtains the values of C1 and C2 from Annex F of DD ENV version of 1993-1-1:1992. for cases with end moments and transverse loading. The equation to evaluate M for mono symmetric sections is given as : cr M cr = C1 π EI s (k x L )2 2 kx k w 2 Iw Is + (k x L )2GI T π 2EI x 2 + (C 2z e − C3z 1) − C2z e − C 3z 1 302 — STAAD. e. C2 and C3 parameters along with CMM values of 7 and 8. which considers the member as a pin ended member with UDL along its span. As described in section (i) above. the proposed implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992 – Annex F. The user however can use the new C1. Both the NCCI documents mentioned above assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member ( k = kw = 1. C . i. CMN = 1. C .0.5 or CMN = 0. A value of K = kw =1 is indicated by a value of CMN = 1. International Design Codes Manual — 303 . The default value of CMM is 1. The current implementation of EC3 in STAAD takes into account of the end conditions using the CMN parameter. CMN = 0. For all cases that are not dealt with by the National Annex (or the NCCI documents) the proposed implementation will use the method as per the DD ENV 1993-1-1:1992 code. and C are dependent on the end conditions and loading criteria. Hence the above methods will be used only for members which are free to rotate on plan and which have no warping restraints. and C as given in the tables below: 1 2 3 The CMM parameter (see section (i) above) specified during design input will determine the values of C1.0). C2 and C3. This 1 2 3 implementation will consider C . For members with partial or end fixities (ie. the user must use C1.7).0 in the design input. C2 and C3 parameters to input the required values for C1..The factors C . C2 and C3 to be used in calculating Mcr. This NCCI does not however consider the “end moments and transverse loading” condition. 0 and β. 7D.Pro .1 c d Rolled doubly symmetric I and H sections and hot-finished hollow sections h/b ≤ 2 2.5 of BS EN 1993-1-1:2005.0 < h/b ≤ 3.75 l For welded sections: λLT.3(1) – LTB for rolled sections or equivalent welded section The UK-NA specifies different values for the λ and β factors to be used in equation 6. By default. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center.3.1 h/b > 3.3 Clause 6. The current implementation in STAAD.Pro uses the buckling curves based on Table 6.0 < h/b ≤ 3.1 Angles (for moments in the major principle plane) All other hot-rolled sections Welded.1. Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero.2 β = 1. The values specified in the UK-NA are: l For rolled sections and hot-rolled & cold formed hollow sections: λLT.00 The current implementation of STAAD.4 β = 0.1-Buckling curves to use with BS EN 1993-1-1:2005 Cross Section Limits Buckling Curve b c d d d h/b ≤ 2 2. The value of ‘zg’ is considered positive if the load acts towards the shear center and is negative if it acts away from the shear center. The user will be allowed to modify this value by using the new ‘ZG’ parameter.0 = 0. doubly symmetric sections and cold-formed hollow sections 304 — STAAD.pro does not differentiate between rolled and welded sections and uses the default values in BS EN 1993-1-1 for λLT.0 BS EN 1993-1-1 for rolled and equivalent welded sections.57 of LT.2. The UK-NA specifies different limits and buckling curves to be used in this clause as given below: Table 7D.0 = 0.The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section. 3. both give equations to evaluate the LTB reduction factor χ to be used in eqn.3 (EN 1993-1-1:2005).3. LT Cl.2.5 in BS EN 1993-1-1:2005 should be replaced with the table given in the NA (See section 4.3.Pro.3.3.3. the program will use the method given in Cl.3.3 of BS EN 1993-1-1:2005 to evaluate χLT l Welded I & H Sections with h/b ≥ 3.3. 7D.2 to evaluate χLT .2 uses tables 6. Table 6.1.. Table 6.2.3 in the UK National Annex states that Table 6.55 of BS EN 1993-1-1:2005. 6.2 to evaluate χ . LT Cl.2.4 to choose the buckling curve and the imperfection factors to be used for calculating χ .. 6. see 6.3 of this document).3 — Calculation of LTB Reduction factor.2.2. “Welded I Sections” and “Any other sections”.2.2.3. 6. In any case the Elastic critical moment “Mcr” (used to evaluate the non dimensional slenderness) will be worked out as given in section 4.2. For any other type of cross section that is not dealt with by the National Annex or Cl. Cl.2 states “Unless otherwise specified.3 to evaluate χ .3.1.3 to choose the buckling curves and imperfection factors.3. Hence for all cases dealt with by the table in the UK NA.3.2(2). Hence for these cases the new implementation will still use the method specified in the base code as per clause 6. 6.3 on the other hand uses tables 6. 6. 6.2. For any case that is not dealt with by Cl. for bending members of constant cross section the value of χ should be determined from.5 and 6. Hence for the following cross sections the program will use the Table in the UK NA for choosing a buckling curve for LTB checks (when the UK NA has been specified): l l l l l Rolled doubly symmetric I & H Sections Rolled doubly symmetric hollow sections (SHS.2.3.3.2.3. Hence in the implementation of EC3 LT (and the UK Annex) in STAAD. this implementation will choose the buckling curves from the UK National Annex.2.3.2.4 Clauses 6.2. 6.2 of BS EN 1993-1-1:2005.2 of this document.2 and 6.5 however only deals with “Rolled I Sections” and “Welded I Sections”.6. χ as per UK NA LT Clauses 6. by default the program will consider clause Cl. Since the UK National Annex uses the NCCIs mentioned in the sections above.3. the program will consider Cl. LT 6. the program will use Cl.1 and welded non-doubly symmetric sections. 6.1 For the following cross sections. CHS) Angle Sections Any other rolled section Welded doubly symmetric sections with h/b < 3.”.This table again does not specify which buckling curve is to be used in case of welded doubly symmetric sections with h/b ≥ 3.3.2 and 6. RHS.2.2. Cl 6.3.3 and 6. For any case that is not dealt with by the table in the UK NA.2. the program will use Cl.3. this implementation will International Design Codes Manual — 305 .4 specifies the choice of buckling curves for “Rolled I LT Sections”. 6. 2 above).. To evaluate the modification factor BS EN 1993-1LT 1:2005 uses a correction factor ‘kc’ given by Table 6. where C1 is to be obtained from the NCCI documents given in section 4. f.58 of BS EN 1993-1-1:2005 to evaluate the modification factor ‘f’ for the LTB reduction factor χ . For all other cases..2 of BS EN 1993-1-1:2005. This proposed implementation will allow for the reduction factor based on the UK-NA.2. Also. the program will use Cl.2.0 in design input).5 Clause 6.3. SBLT parameter = 1.3(2) – Modification factor.e. Note: If a National Annex has not been specified (i.6 in the code.e. 7D. NA parameter in the design input = 0).3. The NCCI document SN003a-EN-EU specifies the values of C1 to be used in table 3.3. specifies that the correction factor ‘kc’ is to be obtained as below: Kc = 1 / √C1.1. this implementation will use the method specified in Annex F of DD ENV 1993-1-1:1992. 6. the program will use Cl. For all other cases of the CMN parameter values.0 (See section 4.only consider end restraint conditions corresponding to the CMN parameter=1. 6. for LTB checks The UK NA specifies the use of eqn.Pro .2. 6. The UK-NA however.1 as shown below.3 only in the case of Rolled or welded I & H Sections. I sections with plates will be treated as built-up sections only if the section has been explicitly specified as a built-up section (i.2 of this document. 306 — STAAD. The user can also get International Design Codes Manual — 307 .7 or 0.0).0 for ‘kc’. However the user can also input a custom value of ‘kc’ by setting the design parameter ‘KC’ to the desired value. The program will use a default value of 1.5) this implementation will use the values of C1 from DD ENV 1993-1-1:1992 Annex F. Hence for all other values of CMN (ie 0.These values are for an end restraint factor of k=1 (ie CMN=1. As per the UK NA.N crTF ). NA-3.3. To evaluate C1. This will cause the program to evaluate a value of C1 corresponding to the end conditions and the Bending moment of the member and in turn calculate ‘kc’ as given in the NA.9 below for details. Hence for non-doubly symmetric sections the program will calculate the critical non-dimensional slenderness as: λ = the maximum of either λ from Cl.3. The proposed implementation will hence use equations in Annex B of BS EN 1993-1-1:2005 to calculate these interaction factors for doubly symmetric sections. In the current implementation this is done as per cl 4.61 and 6. Hence this implementation will use the method specified in the NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” to calculate these.3 and 6.3 or λ from Cl.3. the UK NA gives the option of using Annex B with some modifications as given in the NA.4 y T λT = A fy N cr Where: N = min (N cr CrT . the program will use the NCCI documents mentioned in section 4. (Cl.62 of BS EN 1993-1-1:2005. kyz.10 of BS 5950. 6.1. 308 — STAAD.3(5) – Interaction factors kyy. This proposed implementation will still use the same method for single and double angle sections to evaluate the slenderness. torsional slenderness (λ ) and torsional-flexural slenderness (λ ) as given in Clauses 6.1. 6.7. the slenderness about the weak axis (λy in STAAD) and the corresponding reduction factor χy should be taken as the values from the highest values of slenderness (λ) among the flexural buckling slenderness (λy).pro uses the method in Annex B. The current implementation of EC3 BS in STAAD.3.Pro .1.3. Note: The UK National Annex or EC3 does not deal with angle sections in specific and hence this implementation will use the method used in the current EC3 implementation to deal with slenderness of angle sections. 7D.the program to calculate the value of ‘kc’ automatically by setting the value of the ‘KC’ parameter in the design input to 0.3. The UK NA or EC3 does not however specify a method to evaluate NCrT or NcrTF.4 T TF of BS EN 1993-1-1:2005. However for non-doubly symmetric sections. for non-doubly symmetric sections.6 Clause 6. and kzz The UK-NA recommends that the method in Annex A or Annex B of BS EN 1993-1-1:2005 can be used to calculate the interaction factors for Cl.1.1. The UK NA requires additional checks to be done to check for the maximum allowable values of λ and X to be used in equations 6. kzy. 6.2 of this document.2 of the UK NA). See section 4.3 checks in the case of doubly symmetric sections. Therefore. T 2 iy + i z2 2 io For details on these equations.titled Annexe Nationale a la NF EN 1993-11:2005 . International Design Codes Manual — 309 . Hence for all Class 1 or Class 2 cross sections that are NOT I.3. T = 1 2 io GI t + π EI w I T2 2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively.TF cr.4 .1.4(2)B – Modification factor ‘kfl’ STAAD.T these methods are used to evaluate the elastic critical loads for the UK NA. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr.Clause NA 3. T) 2 − 4Ncr.3. this clause is ignored for the French National Annex. the elastic properties will be used for the purposes of 6. 7D.Pro does not use this clause for design per EC-3. refer to the NCCI document SN001a-EN-EU. y + Ncr. it will be treated as a class 3 section for the purposes of this clause”. Clause 6.2 of the UK NA also requires that “Where the section is not an I Section or a hollow section and is a class1 or class 2 section. The NA document makes small changes to the base document.3 checks. this clause is ignored for the French National Annex.F cr.Slenderness for torsional and torsional-flexural buckling Equations 6.2. yN cr. T − (Ncr.Pro: Clause 6. The NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and therefore cr.2. or EN 1993-1-1:2005.53 of BS EN 1993-1-1:2005 are to be used to calculate the non-dimensional slenderness λ .T 6. 7D.52 and 6. The following clauses are not implemented in STAAD.3. RHS or CHS sections. SHS. H.1.4(1) B – Slenderness for flexural buckling STAAD. to be used for torsional and torsional-flexural buckling checks. Therefore.for use with Eurocode 3.2 French National Annex to EC3 Adds values from the French National Annex . y + Ncr.14 of BS EN 1993-1-1:2005). BS EN 1993-1T 1:2005 does not provide equations to calculate the elastic critical loads N and N (refer cr.Pro does not use this clause for design per EC-3.7 Clause 6.3.T. TF = 2 io 2 2 2 iy +iz ( ) Ncr. The critical axial load for Torsional buckling is evaluated as: Ncr.3. 1 Clause 3. The sections below refer to the corresponding clauses in the French-NA.1 in EC3. Table 3.Pro .2. Table 3.1 in NF EN 1993-1-1:2005.1 NF).e. apart from the f values for S 355 and u S355 W grade steel..Pro uses the steel grades and values from the table given in the National Annex (i.2-Material strengths specified for use with the NF-NA Nominal thickness.1 NF) for the yield and tensile strengths of steel grades. t.e..steel grade strengths) to be used with NF EN 1993-1-1 are given in Table 3. specifies a separate table (Table 3. STAAD.1 NF is similar to table 3. . Table 7D.1 NF excludes steel grades from standards EN 10210-1 and EN 10219-1 that are given in EC-3. of the element (mm) Standard and grade of steel t 40 mm f y (N/mm 2) S 235 EN 100252 S 275 S 355 S 450 S 275 N/NL EN 100253 S 355 N/NL S 420 N/NL S 460 N/NL 235 275 355 440 275 355 420 460 f u (N/mm 2) 360 430 490 550 390 490 520 540 40 mm < t <= 80 mm f y (N/mm 2) 215 255 335 410 255 335 390 430 f u (N/mm 2) 360 410 470 550 370 470 520 540 310 — STAAD. The French National Annex however. Table 3.1(1) . This new table replaces Table 3.1 of the code. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that have been dealt with in the French National Annex (hereafter referred to as FR-NA) and that are relevant to the proposed implementation are: 7D.Note: Refer to the basic code (EC3) for a description of these clauses.2.Material Properties The material strengths (i. 1 of EN 1993-1-1:2005.1 (NF) but is present in Table 3. 6. GM1.0 M1 Resistance of members to instability.2. and γ . The partial safety factors will use the following values for the French National Annex: l l l Resistance of cross-sections. y 7D.Nominal thickness.0 = 1. γ M2 The design function in STAAD. of the element (mm) Standard and grade of steel t 40 mm f y (N/mm 2) S 275 M/ML EN 100254 S 355 M/ML S 420 M/ML S 460 M/ML EN 100255 EN 100256 S 235 W S 355 W S 460 Q/QL/QL 1 275 355 420 460 235 355 460 f u (N/mm 2) 370 470 520 540 360 490 570 40 mm < t <= 80 mm f y (N/mm 2) 255 335 390 430 215 335 440 f u (N/mm 2) 360 450 500 530 340 490 550 If you specify a steel grade that is not given in the Annex Table 3. EN 1993 provides default values for M0 M1 M2 these factors. See "Design Parameters" on page 264 International Design Codes Manual — 311 . γ = 1.2 Clause 6.25 Resistance of cross sections to tension.Pro sets these values as the default values for the NF-NA (NA 4 is specified). Note: You can change these values through the GM0.1 of the code. t. & GM2 design parameters. the program uses the values from Table 3. γ . any National Annex is allowed to override these default values.1(1) – General EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl. These factors are γ . The appropriate yield strength (f ) used is shown in the design output file.1 of EN 1993-1-1:2005. γ M0 = 1. However. For mono symmetric sections that are symmetric about the minor axis (i. Annex MCR however deals with the calculation of Mcr for doubly symmetric sections. The equation to evaluate M is given as: cr M cr = C1 π EI s (kL ) 2 2 k k w 2 Iw Is + (kL ) GI t π EI s 2 2 + (C2z s)2 − C2z s C and C are factors that depend on the end conditions and the loading conditions. this implementation will use the method and tables given in Annex F of DD ENV 1993-1-1:1992. 7D. 0) and use the default values as given above. The calculation of the LTB reduction factor χ . The French NA gives a method to evaluate M in its “Annex cr cr MCR”. Warning: The GB1 parameter that is being used for compression checks in builds preceding this release (STAAD.3 Clause 6.2. This implementation will make use of this method to evaluate Mcr.Pro .Pro will ignore the user specified value (i. requires the calculation of the “Elastic LT Critical Buckling Moment”. Annex MCR This document provides a method to calculate M specifically for doubly symmetric sections cr only.Pro 2007 build 06) has been removed as this parameter is no longer required in EN 1993-1-1:2005.2 –Elastic critical moment and imperfection factors for LTB checks The French NA recommends the use of Table 6. 1 Clause 3.3 and 6.3. Hence. Table 1 deals with the condition of a simply supported member with end moments and the value of C is determined by the end moment ratio (Refer to the NA for details).2 of the National Annex however gives a formula to evaluate C as: 1 C1 = 1 0.. Hence this implementation will use this method only for doubly symmetric sections.252ψ 2 312 — STAAD.325 + 0.4 of NF EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks. Hence only doubly symmetric sections will be considered for this method in this implementation. M . For any other type of section that is not dealt with by the Annex. STAAD. any legacy files that use GB1 parameter will indicate an error message and the user will need to substitute GB1 with GM1 in line with EN 1993-1-1:2005.e Tee sections) this implementation will use the method from the NCCI document SN030a-EN-EU as given in the section below.423ψ + 0.e. The 1 2 NCCI provides values for C and C for the different cases as given in Table1 and Table 2 of the 1 2 Annex.Note: If any of these parameters are specified as 0.2. The load to moment ratio (μ) to be used in the calculations is to be input using the new ‘MU’ parameter. Note: The new parameter MU will currently be applicable only in the context of the French NA. Hence this implementation will introduce two new values for CMM viz. For all other cases this implementation will calculate the value of C1 from equation (6) in the Annex. International Design Codes Manual — 313 . The load to moment ratio (μ) will then be used in the calculations will then be used to calculate C1 and C2 as given in section 3. This implementation will require that for the French National Annex if CMM = 7 or 8 has been specified. The value of C2 will be determined from Table 2 of the Annex based on the loading and end conditions (i. Hence for this implementation the elastic critical moment for ‘Tee-Sections’ will be worked out using the method in this NCCI. the user should also either specify a value for ‘MU’ or input the values for C1 and C2 using the ‘C1’ and/or ‘C2’ parameters directly.e the CMM parameter in STAAD).5 of Annex MCR (See Annex MCR in the NA for details). Hence this implementation will use the values of C1 from Table 1 if the end moment ration (ψ) is exactly equal to the values of ψ in the table. SN030a-EN-EU – Mono-symmetrical uniform members under bending and axial compression: This document provides a method to evaluate the elastic critical moment (Mcr) for uniform mono symmetric sections that are symmetric about the weak axis. This implementation will also introduce a new parameter ‘MU’ to be specified when using CMM = 7 or 8. The first two cases and its variants can be defined using with the existing CMM parameter values in STAAD. CMM 7:Member with varying end moments and uniform loading.This formula however does not match the values given in Table 1 of the NA. The user will also have the option to specify specific values for C and C using the C1 and C2 1 2 parameters in the design input mode. However the third condition cannot be currently specified in the design input. See "Design Parameters" on page 264 The French NA considers three separate loading conditions: l l l Members with end moments Members with transverse loading Members with end moments and transverse loading. CMM 8: Member with varying end moments and central point load.Pro. Hence this implementation will use this method only for Tee-Sections. The default value of CMM is 0. 314 — STAAD. The equation to evaluate M for mono symmetric sections is given as: cr M cr = C1 π EI s (k x L )2 2 kx k w 2 Iw Is + (k x L )2GI T π 2EI x 2 + (C 2z e − C3z 1) − C2z e − C 3z 1 The factors C .Pro . The user however can use the new ‘C1’. ‘C2’ and ‘C3’ parameters to input the required values for C1. and C are dependent on the end conditions and loading criteria. STAAD.Note: Though this method could also be applicable to mono-symmetric built-up sections. C . This NCCI does not however consider the “end moments and transverse loading” condition. which considers the member as a pin ended member with UDL along its span. C . and C as given in the tables below: 1 2 3 The CMM parameter specified during design input will determine the values of C1. This 1 2 3 implementation will consider C . C2 and C3.Pro currently does not have a means to specify/identify a monosymmetric built-up section. C2 and C3 to be used in calculating Mcr. C2 and C3 have been specified. Again this document does not give any specific formulae to evaluate the coefficients. STAAD.2. C2 and C3. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center.0 to 0.4 − 0. The use will be allowed to modify this value by using the ZG parameter.3 b h International Design Codes Manual — 315 . For welded doubly symmetric sections use: λLT .. CMN parameter =1.3 αLT = 0.Pro limits λLT.4.Pro obtains these values from Annex F of DD ENV version of 1993-1-1:1992. CMN = 0. Hence the above methods will be used only for members which are free to rotate on plan and which have no warping restraints.Note: If ‘MU’ as well as C1. the NCCI document and Annex MCR of the FR-NA assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member( k = kw=1 .1 b h LT. 0 = 0.0).Pro. Note: There is a separate method specified in the NCCI document “SN006a-EN-EU” to calculate Mcr for cantilever beams. Hence.2.i.4 Clause 6. 0 = 0. the program will ignore MU and use the user input values of C1. if the load acts towards the shear center and is negative if it acts away from the shear center.0 and α LT factors given in clause 6. this has not been implemented in STAAD.3(1) – LTB for rolled sections or equivalent welded section The FR-NA provides equations to evaluate the λ For rolled doubly symmetric sections use: λLT . 7D. For members with partial or end fixities (ie.5 or CMN = 0.e.0 to a maximum value of 0. Also. For all cases that are not dealt with by the National Annex (or the NCCI documents) this implementation will use the method as per the DD ENV 1993-1-1:1992 code. this implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992. The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section. The current implementation of EC3 in STAAD.2 + 0.4. The value of ‘zg’ is considered positive.3.2.7). Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero. By default.2 λLT ≥ 0 b 2 h Note: Since EN 1993-1-1:2005 limits the value of λLT.3. 0 These equations and factors are then applied to equation 6.5 Clause 6.e. f.mod LT 7D. An additional check will also be performed as given below: χLT .αLT = 0.. This will correspond to the end conditions and the bending moment of the member (i.2 αLT = 0.3.82 based on the end moment ratio.Pro . this implementation will ignore ‘f’ and hence will use χ = χ .e.57 of NF EN 1993-1-1 to evaluate the Lateral Torsional Buckling reduction factor χ . LT 7D.3(5) – Interaction factors kyy.6 Clause 6.91 based on the end moment ratio.2. Hence this implementation will use the existing functionality to evaluate the correction factor kc to be used in the modification factor f. the program will choose the value of kc to be either 0. for LTB checks The French NA specifies that the modification factor is to be obtained as per the default method given in EC-3.0 = 0.25 λLT ≥ 0 b 2 h For other sections: λLT. mod ≤ 1 λ LT 2 The French Annex specifies that the modification factor is applicable only to members that are free to rotate on plan (i. LT. Hence for all other values of CMN. Therefore. CMN 1. 316 — STAAD. kzy.6 of NF EN 1993-11:2005.pro uses the method in Annex B for design per EC3 (without National Annex).3(2) – Modification factor.0 for kc. However the user can also input a custom value of kc by setting the design parameter KC to the desired value. For CMM = 8..0). You may instruct the program to calculate the value of kc automatically by setting the value of the KC parameter in the design input to 0.5 − 0. the program will choose the value of kc to be either 0. β = 1. STAAD.2.76 And for all sections. and kzz The French NA recommends the use of equations in Annex A of NF EN 1993-1-1:2005 to calculate these interaction factors.3.2. This will cause the program to evaluate kc from Table 6. the value of CMM parameter specified). The program uses a default value of 1. kyz. the method in Annex A has been added into the program.77 or 0.90 or 0. For CMM = 7. F cr.53 of NF EN 1993-1-1:2005 are to be used to calculate the non-dimensional slenderness λ .i 7D.52 and 6. 0 ≥ 1 − N Ed N cr . The critical axial load for Torsional buckling is evaluated as: Ncr.T. TF = 2 io 2 2 2 iy +iz ( ) Ncr.Slenderness for torsional and torsional-flexural buckling" on page 317 The NA also recommends a lower limit as given below for the term C in Table A.7 Clause 6. This is taken into account based on the method given in the NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes”. refer to the NCCI document SN001a-EN-EU.14 of NF EN 1993-1-1:2005). T) 2 − 4Ncr.3.1.3. T 2 iy + i z2 2 io For details on these equations. yN cr.T 6.4 .TF cr. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr.0 Annex A: Cmi. since STAAD does not have a provision to specify such sections. International Design Codes Manual — 317 . However.Note: The NA mentions that this method can be extended to singly symmetric I-Sections (symmetric about the minor axis) if the elastic properties are used instead of the plastic properties.Slenderness for torsional and torsional-flexural buckling Equations 6. The NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and therefore cr.T these methods are used to evaluate the elastic critical loads for the French NA. See "Clause 6. NF EN 1993-1T 1:2005 does not provide equations to calculate the elastic critical loads N and N (refer cr. T = 1 2 io GI t + π EI w 2 I T2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively. T − (Ncr. this case will not be considered for this implementation.1.2. y + Ncr. The NA also mentions that torsional flexural buckling needs to be taken into account in case of mono symmetric sections.3. y + Ncr.2 of mi.4 . to be used for torsional and torsional-flexural buckling checks. S315NC.2.Pro does not use this clause for design per EC-3. These factors are γ . The following clauses are not implemented in STAAD.1(2) that.4(1) B – Slenderness for flexural buckling STAAD. any National Annex is allowed to override these default values.2. γ .3 Finnish National Annex to EC3 Adds values from the Finnish National Annex . Clause 6. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that have been dealt with in the Finnish National Annex (hereafter referred to as SFS-NA) and that are relevant to the proposed implementation are: 7D. The partial safety factors will use the following values for the Finnish National Annex: 318 — STAAD. The sections below refer to the corresponding clauses in the Finnish-NA. S355NC and S420NC according to SFS-EN 10149-3 These grades of steel can be specified by using the PY (Yield Strength) and FU (Ultimate Strength) parameters in STAAD. this clause is ignored for the Finnish National Annex.1 of the code.1 of SFS EN 1993-1-1.1(1) – General EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl. 6.Material Properties The material strengths (i. steel grade strengths) to be used with SFS-EN 1993-1-1 are given in Table 3.1 of the code.Pro .Pro: Clause 6. apart from the steel grades specified in Table 3. and γ .for use with Eurocode 3. 7D.3. The choice of the buckling curve to be used is based on the value of the SGR parameter specified.titled National Annex to Standard SFS-EN 1993-1-1 . Set these parameters to the respective values as given in SFS-EN 10149-2/3 for the steel grades specified above. The output will include the appropriate yield strength used for design.Pro. Therefore. The NA document makes small changes to the base document. S355MC.3.Pro does not use this clause for design per EC-3. The Finnish National Annex states in Cl.e.1 Clause 3. this clause is ignored for the Finnish National Annex. EN 1993 provides default values for M0 M1 M2 these factors.2.3.2 Clause 6. S420MC and S460MC according to SFS-EN 10149-2 Steel grades S260NC. Therefore.7D. or EN 1993-1-1:2005.4(2)B – Modification factor ‘kfl’ STAAD.3. These steel grade values are specified using the SGR parameter (See "Design Parameters" on page 264).. Note: Refer to the basic code (EC3) for a description of these clauses. the following steel grades can also be used: l l Steel grades S315MC. However. 3.1(1) . 2. 0) and use the default values as given above. Hence the calculation of M has been based on the following NCCI documents: cr cr 1. GM1.e. The NCCI provides values for C and C for the different cases as given in 1 2 the tables below: International Design Codes Manual — 319 .Pro will ignore the user specified value (i. γ M2 The design function in STAAD.25 Resistance of cross sections to tension. γ M0 = 1. Note: You can change these values through the GM0. 7D.Pro 2007 build 06) has been removed as this parameter is no longer required in EN 1993-1-1:2005. Hence.l l l Resistance of cross-sections. M .Pro sets these values as the default values for the SFS-NA (NA 5 is specified).2 –Elastic critical moment and imperfection factors for LTB checks The Finnish NA recommends the use of Table 6.3 Clause 6. STAAD.3 and 6. any legacy files that use GB1 parameter will indicate an error message and the user will need to substitute GB1 with GM1 in line with EN 1993-1-1:2005. SN003a-EN-EU – Elastic critical moment for Lateral torsional Buckling: This document provides a method to calculate M specifically for doubly symmetric cr sections only. See "Design Parameters" on page 264 Note: If any of these parameters are specified as 0.3. The Finnish National Annex does not specify a particular method to cr calculate M . γ = 1.. The calculation of the LTB reduction factor χ . Hence only doubly symmetric sections will be considered for this method. The equation to evaluate M is given in the NCCI as: cr M cr = C1 π EI s (kL ) 2 2 2 k Iw k I + w s (kL ) GI t π EI s 2 2 + (C2z s)2 − C2z s C and C are factors that depend on the end conditions and the loading conditions of 1 2 the member.4 of SFS EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks.0 M1 Resistance of members to instability. requires the calculation of the ‘Elastic Critical LT Buckling Moment’. Warning: The GB1 parameter that is being used for compression checks in builds preceding this release (STAAD.3. & GM2 design parameters.0 = 1. 25 -0. the elastic critical moment for ‘Tee-Sections’ will be worked out using the method in this NCCI.Pro .05 2. The equation to evaluate M for mono symmetric sections is given as : cr 320 — STAAD. 2. STAAD.77 2.52 1.00 +0.50 +0. Hence. STAAD.3-Values of C for end 1 moment loading (for k=1) ψ +1.Pro accounts for the loading condition and the bending moment diagram through the CMM parameter. Hence this implementation will use this method only for Tee-Sections.Pro currently does not have a means to specify/identify a mono-symmetric built-up section.75 C 1 1.25 0.57 This NCCI considers three separate loading conditions: l l l Members with end moments Members with transverse loading Members with end moments and transverse loading.50 -0. Note: Though this method could also be applicable to mono-symmetric built-up sections.00 1.31 1.Table 7D.00 -0.33 2. SN030a-EN-EU – Mono-symmetrical uniform members under bending and axial compression: This document provides a method to evaluate the elastic critical moment (M ) for cr uniform mono symmetric sections that are symmetric about the weak axis.75 +0.14 1. and C to be used in calculating M . C2. Both the NCCI documents mentioned above assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member ( k = kw = 1. A value of K = kw =1 is indicated by a value of CMN = 1. C2. STAAD. Hence the above methods will be used only for members which are free to rotate on plan and which have no International Design Codes Manual — 321 . and C3. and C3 parameters to input the required values for C . and C3 have been specified.Pro takes into account of the end conditions using the CMN parameter for EC3. and C as given in the tables below: 1 2 3 The CMM parameter specified during design input will determine the values of C . C . and C are dependent on the end conditions and loading criteria. This NCCI does not however consider the “end moments and transverse loading” condition.M cr = C1 π EI s (k x L )2 2 kx k w 2 Iw Is + (k x L )2GI T π EI x 2 2 + (C 2z e − C3z 1) − C2z e − C 3z 1 The factors C . STAAD. The default value of CMM is 0. the program will ignore MU and use the user input values of C1.0 in the design input.0). 1 2 3 This implementation will consider C . C . 1 2 3 cr Note: If MU as well as C1. C . which considers the member as a pin ended 3 member with UDL along its span. C . 1 2 and C . C2. You can use the C1.Pro obtains these values from Annex F of DD ENV version of 1993-1-1:1992. if the load acts towards the shear center and is negative if it acts away from the shear center.4 and β = 0. The value of ‘zg’ is considered positive.2.3.0 =0.7). CMN = 0.0 as follows: For rolled doubly symmetric sections and hollow sections. this has not been implemented in STAAD.e. Again this document does not give any specific formulae to evaluate the coefficients.57) Cross-section (constant cross-section) Rolled double symmetric I. Note: There is a separate method specified in the NCCI document “SN006a-EN-EU” to calculate Mcr for cantilever beams.0). this implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992 – Annex F. 7D.4 Clause 6.warping restraints (i. CMN = 1. By default..e. Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero.sections and hot finished hollow sections.2 and β = 1.5 or CMN = 0.and H. For all cases that are not dealt with by the National Annex (or the NCCI documents) this implementation will use the method as per the DD ENV 1993-1-1:1992 code.0 The Finnish NA specifies the following limits for choosing the buckling curves: Table 7D.1 b c 322 — STAAD.75 For welded doubly symmetric sections and hollow sections use: λ LT. The use will be allowed to modify this value by using the ZG parameter.3(1) LT.3(1) – LTB for rolled sections or equivalent welded section The Finnish-NA provides the values for the terms λ and β factors given in clause 6.4-Selection of lateral torsional buckling curve for cross sections using equation (6. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center.Pro.0 = 0.2. Limits Buckling Curve h/b ≤ 2 2< h/b <3. The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section. For members with partial or end fixities (i. Hence.3.3..Pro . use: λ LT. 2.2. the program will consider Cl.2.2 states “Unless otherwise specified. (used to evaluate the non dimensional slenderness) will be evaluated as previously given.3 in the Finnish National Annex gives equations to evaluate the imperfection factors to be used for various section types (See "Clause 6. LT 6.3. 6.3 to evaluate χ . Cl.2.2.3 (EN 1993-1-1:2005).2. this implementation will use the method specified in Annex F of DD ENV 1993-1-1:1992.3. the program will use Cl.Cross-section (constant cross-section) Welded double symmetric I.3. for bending members of constant cross section the value of χ should be determined from. LT Cl.section and H.3.2.2 should be used.sections and cold-formed hollow sections Limits Buckling Curve h/b ≤ 2 2< h/b < 3. the elastic critical moment.3.2.3 — Calculation of LTB Reduction factor.3. LT For any other type of cross section that is not dealt with by the National Annex or Cl.2.3.1 c d The NA says that for all other cases the rules given in Cl 6. 6.2.2.3.2 to evaluate χ . χ as per Finnish NA LT Clauses 6.5 Clauses 6.55 of SFS EN 1993-1-1:2005.3. International Design Codes Manual — 323 .. Cl 6.2. LT Cl.”.3.. 6. “Welded I Sections” and “Any other sections”.1.2. Mcr.2 and 6.3 to evaluate χ .2.57 of SFS-EN 1993-1-1 to evaluate the Lateral Torsional Buckling reduction factor χ .6. For any case that is not dealt with by Cl.3. Table 6.3 on the other hand uses tables 6.2.3.3. 6. LT In any case. both give equations to evaluate the LTB reduction factor χ to be used in eqn.3.3.3.2.2. Hence even for rolled or welded doubly symmetric sections with h/b ratio ≥ 3.4 specifies the choice of buckling curves for “Rolled I LT Sections”. 6.2.2 to evaluate χ .2.3.2.3 to choose the buckling curves and imperfection factors.3. this implementation will resort to checks as per clause 6.2 and 6. Since this implementation uses the NCCIs mentioned in the sections above.3.2 –Elastic critical moment and imperfection factors for LTB checks" on page 319 ). For all other cases of the CMN parameter values. 6.3 and 6.2 uses tables 6. 6.3.5 and 6.3. Table 6.2 –Elastic critical moment and imperfection factors for LTB checks" on page 319 ) will be considered. These equations and factors are then applied to equation 6. Hence in the implementation of EC3 LT (and the Finnish Annex) in STAAD. LT 7D.3. see 6. only end restraint conditions corresponding to the CMN parameter=1.Pro: by default the program will consider clause Cl.3. Hence for all cases dealt with by the equations in the Finnish NA.5 however only deals with “Rolled I Sections” and “Welded I Sections”. this implementation will use Cl 6.4 to choose the buckling curve and the imperfection factors to be used for calculating χ .0 (See "Clause 6. 3(2) – Modification factor. cr.T these methods are used to evaluate the elastic critical loads for the Finnish NA.3.3.3. kzy. For all other cases. TF = 2 io 2 2 2 iy +iz ( ) Ncr.TF cr. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr. the program will use Cl.3(5) – Interaction factors kyy.3. SBLT parameter = 1.T The NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and therefore cr.Note: If a National Annex has not been specified (i. I sections with plates will be treated as built-up sections only if the section has been explicitly specified as a built-up section (i.T. STAAD. 7D.2. The critical axial load for Torsional buckling is evaluated as: Ncr. T = 1 2 io GI t + π EI w 2 I T2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively. T SFS EN 1993-1-1:2005 does not provide equations to calculate the elastic critical loads N cr..0 in design input). 7D.e. Also.Pro uses the method in Annex B by default. T − (Ncr.4 . y + Ncr.2 of BS EN 1993-1-1:2005. to be used for torsional and torsional-flexural buckling checks.0 as given in the Finnish NA.14 of SFS EN 1993-1-1:2005). f. for LTB checks STAAD.2. NA parameter in the design input = 0).Slenderness for torsional and torsional-flexural buckling Equations 6.3. yN cr.F and N (refer 6.3.3 checks.6 Clause 6..52 and 6.Pro .2.e. y + Ncr.3.1.3.6. T 2 iy + i z2 2 io 324 — STAAD.3. and kzz The Finnish NA recommends the use of equations in Annex A or Annex B of SFS-EN 1993-1-1 to calculate these interaction factors.3 only in the case of Rolled or welded I & H Sections.Pro uses the value of the modification factor f = 1. T) 2 − 4Ncr.3. 7D.8 Clause 6. This implementation of the Finnish NA will also use Annex B for Cl. kyz.7 Clause 6. the program will use Cl.53 of SFS EN 1993-1-1:2005 are to be used to calculate the nondimensional slenderness λ . 6. 6. 1 Clause 3. Therefore.3. γ = 1. this clause is ignored for the Polish National Annex.4.2.2. Note: Refer to the basic code (EC3) for a description of these clauses. γ .1(2) that the steel grades to be used will be based on Table 3. and γ . Therefore. These steel grade values are specified using the SGR parameter (See "Design Parameters" on page 264). this clause is ignored for the Polish National Annex.1 of PN EN 1993-1-1.2.4(1) B – Slenderness for flexural buckling STAAD. 7D.1(1) – General EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that have been dealt with in the Polish National Annex (hereafter referred to as PN-NA) and that are relevant to the proposed implementation are: 7D. The Polish National Annex states in Cl.1 or 0..2 Clause 6. or EN 1993-1-1:2005.e.0 = minimum of 1.Pro: Clause 6.0 M1 Resistance of members to instability.3. However.Pro does not use this clause for design per EC-3.4(2)B – Modification factor ‘kfl’ STAAD.titled National Annex to Standard PN-EN 19931-1 . EN 1993 provides default values for M0 M1 M2 these factors. These factors are γ . γ M0 = 1. The partial safety factors will use the following values for the Polish National Annex: l l l Resistance of cross-sections. The following clauses are not implemented in STAAD.4 Polish National Annex to EC3 Adds values from the Polish National Annex . 7D. γ M2 Where: f is the ultimate steel strength u y f is the yield strength of steel International Design Codes Manual — 325 . refer to the NCCI document SN001a-EN-EU.for use with Eurocode 3.Pro does not use this clause for design per EC-3.1(1) .For details on these equations. The sections below refer to the corresponding clauses in the Polish-NA. steel grade strengths) to be used with PN-EN 1993-1-1 are given in Table 3.Material Properties The material strengths (i. 3.9 x f /f u y Resistance of cross sections to tension. The NA document makes small changes to the base document.1 of the code.4. Clause 6. 6. any National Annex is allowed to override these default values.1 of the code. Hence only doubly symmetric sections will be considered for this method.2 –Elastic critical moment and imperfection factors for LTB checks The Polish NA recommends the use of Table 6.4 of PN EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks.3. 0) and use the default values as given above. any legacy files that use GB1 parameter will indicate an error message and the user will need to substitute GB1 with GM1 in line with EN 1993-1-1:2005.The design function in STAAD. 7D.Pro . & GM2 design parameters.e.Pro will ignore the user specified value (i. The equation to evaluate M is given in the NCCI as: cr M cr = C1 π EI s 2 k Iw + (kL ) 2 k w I s 2 (kL ) GI t π 2EI s 2 + (C2z s)2 − C2z s C and C are factors that depend on the end conditions and the loading conditions of 1 2 the member. GM1. M . The NCCI provides values for C and C for the different cases as given in 1 2 the tables below: 326 — STAAD. STAAD. Note: You can change these values through the GM0. The Polish National Annex does not specify a particular cr method to calculate M . Warning: The GB1 parameter that is being used for compression checks in builds preceding this release (STAAD. The calculation of the LTB reduction factor χ . Hence.2.Pro sets these values as the default values for the PN-NA (NA 6 is specified).4.. SN003a-EN-EU – Elastic critical moment for Lateral torsional Buckling: This document provides a method to calculate M specifically for doubly symmetric cr sections only.3 Clause 6. requires the calculation of the ‘Elastic LT Critical Buckling Moment’. Hence the calculation of M has been based on the following NCCI cr cr documents: 1.Pro 2007 build 06) has been removed as this parameter is no longer required in EN 1993-1-1:2005. See "Design Parameters" on page 264 Note: If any of these parameters are specified as 0.3 and 6. 52 1. Note: Though this method could also be applicable to mono-symmetric built-up sections.31 1.50 -0. the elastic critical moment for ‘Tee-Sections’ will be worked out using the method in this NCCI.75 +0.Pro accounts for the loading condition and the bending moment diagram through the CMM parameter. STAAD.75 C 1 1.14 1.25 0.00 +0. Hence. SN030a-EN-EU – Mono-symmetrical uniform members under bending and axial compression: This document provides a method to evaluate the elastic critical moment (M ) for cr uniform mono symmetric sections that are symmetric about the weak axis.05 2.Table 7D.Pro currently does not have a means to specify/identify a mono-symmetric built-up section. 2. Hence this implementation will use this method only for Tee-Sections.50 +0.25 -0. The equation to evaluate M for mono symmetric sections is given as : cr M cr = C1 π EI s (k x L )2 2 kx k w 2 Iw Is + (k x L )2GI T π EI x 2 2 + (C 2z e − C3z 1) − C2z e − C 3z 1 International Design Codes Manual — 327 .00 -0.33 2.00 1.5-Values of C for end 1 moment loading (for k=1) ψ +1.77 2. STAAD.57 This NCCI considers three separate loading conditions: l l l Members with end moments Members with transverse loading Members with end moments and transverse loading. Both the NCCI documents mentioned above assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member ( k = kw = 1. You can use the C1. and C as given in the tables below: 1 2 3 The CMM parameter specified during design input will determine the values of C . The default value of CMM is 0.The factors C . For members with partial or end fixities (i. CMN = 1. STAAD. C .e. which considers the member as a pin ended 3 member with UDL along its span.0). C . and C to be used in calculating 1 2 3 M .Pro . Hence the above methods will be used only for members which are free to rotate on plan and which have no warping restraints (i.0). the program will ignore MU and use the user input values of C1. and C3 have been specified. C2. STAAD.. and C3. 1 2 3 This implementation will consider C .0 in the design input. 1 2 and C .5 328 — STAAD. A value of K = kw =1 is indicated by a value of CMN = 1. C .Pro takes into account of the end conditions using the CMN parameter for EC3. CMN = 0.e.Pro obtains these values from Annex F of DD ENV version of 1993-1-1:1992. cr Note: If MU as well as C1. C2. C2. C . and C3 parameters to input the required values for C . and C are dependent on the end conditions and loading criteria.. This NCCI does not however consider the “end moments and transverse loading” condition. χ as per Finnish NA LT Clauses 6. Hence.4.7). Cl 6.3. For all cases that are not dealt with by the National Annex (or the NCCI documents) this implementation will use the method as per the DD ENV 1993-1-1:1992 code.3. 6.3. LT Cl. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center. LT 7D. if the load acts towards the shear center and is negative if it acts away from the shear center.4.3 on the other hand uses tables 6. Table 6.3 to choose the buckling curves and imperfection factors.75 The Polish NA specifies the use of uses table 6.3. By default.2. These equations and factors are then applied to equation 6.5 in PN-EN 1993-1-1 will be used for this. Table 6.3. this has not been implemented in STAAD.3 and 6.2. International Design Codes Manual — 329 .3.5 to work out the buckling curves for use in Cl.3.4 specifies the choice of buckling curves for “Rolled I LT Sections”.4 to choose the buckling curve and the imperfection factors to be used for calculating χ .3. both give equations to evaluate the LTB reduction factor χ to be used in eqn.3(1) as LT.2.2.2 and 6.5 and 6.3(1) – LTB for rolled sections or equivalent welded section The Polish-NA provides the values for the terms λ and β factors given in clause 6. The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section.Pro.3.2.3 (EN 1993-1-1:2005).57 of PN-EN 1993-1-1 to evaluate the Lateral Torsional Buckling reduction factor χ . The use will be allowed to modify this value by using the ZG parameter.3.4 Clause 6.2 uses tables 6.2 and 6.0 follows: For all sections. Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero. The value of ‘zg’ is considered positive. 7D. Hence table 6.4 and β = 0.or CMN = 0.55 of PN EN 1993-1-1:2005. Again this document does not give any specific formulae to evaluate the coefficients.3 — Calculation of LTB Reduction factor.2. Note: There is a separate method specified in the NCCI document “SN006a-EN-EU” to calculate Mcr for cantilever beams.2.5 Clauses 6. 6.5 however only deals with “Rolled I Sections” and “Welded I Sections”. “Welded I Sections” and “Any other sections”. 6.0 =0. use: λ LT.2. this implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992 – Annex F.2. 3..3.6 Clause 6. LT In any case.Pro uses the value of the modification factor f as per eqn 6.2. Hence for all cases dealt with by the equations in the Finnish NA. kzy.3 of PN-EN 1993-1mLT 1. NA parameter in the design input = 0). Hence in the implementation of EC3 LT (and the Finnish Annex) in STAAD.3 to evaluate χ . 6.e. for bending members of constant cross section the value of χ should be determined from.2.2 states “Unless otherwise specified. For any case that is not dealt with by Cl. M . 7D. Also. Note: If a National Annex has not been specified (i. Since this implementation uses the NCCIs mentioned in the sections above.2.”. and kzz The Polish NA recommends the equations in Annex B of PN-EN 1993-1-1 to calculate these 330 — STAAD.3 in the Finnish National Annex gives equations to evaluate the imperfection factors to be used for various section types (See "Clause 6.2.2 to evaluate χ .2.3. 6.3.2.2. C is evaluated based on the end conditions of the member and the shape mLT of the bending moment diagram.. then the program will use the specified value.2 of BS EN 1993-1-1:2005.3 to evaluate χ . for LTB checks STAAD.3. if the KC parameter has been used. I sections with plates will be treated as built-up sections only if the section has been explicitly specified as a built-up section (i.3.2 –Elastic critical moment and imperfection factors for LTB checks" on page 319 ).3.3. 6.6. this implementation will use the method specified in Annex F of DD ENV 1993-1-1:1992. LT For any other type of cross section that is not dealt with by the National Annex or Cl. SBLT parameter = 1.3.3(2) – Modification factor. 6.3. the program will consider Cl.Pro: by default the program will consider clause Cl.3.2. For all other cases of the CMN parameter values.3. f.3 only in the case of Rolled or welded I & H Sections. The correction factor ‘kc’ will be evaluated as: kc = √(CmLT) Where: C is the equivalent uniform moment factor from table B. kyz.3.e. 7D.2. the program will use Cl. only end restraint conditions corresponding to the CMN parameter=1.3.3.2 –Elastic critical moment and imperfection factors for LTB checks" on page 319 ) will be considered. 6.2.0 (See "Clause 6. (used to evaluate the non dimensional cr slenderness) will be evaluated as previously given.Pro .Cl. 6. the elastic critical moment..2.2.3. 6. the program will use Cl. However.7 Clause 6. For all other cases. this implementation will use Cl 6. LT 6. LT Cl. the program will use Cl.2.2.3(5) – Interaction factors kyy.2 to evaluate χ .0 in design input).3.. see 6.4.58 of PN-EN 1993-1-1.4.3. interaction factors. the user can invoke these checks by using the PLG parameter.3: Eqn6.2 (w – 1).i . by default. However as they are intended as optional checks.3: Eqn6. n/χ + [(k m )2 + (C i ii i mj m )2] 1/2 ≤ 1 (i. Rd .the interaction factor from table B.LTB factor C . m. Cmj are as above. or Δ = 0.20(3) respectively: l Cl.Ed my m /χ y LT + C mz m with ≤ 1. the following two checks will be performed as per Cl.(3): This condition will only be checked for circular hollow sections. See "Design Parameters" on page 264 If the value of the PLG parameter is set to 1.3.z) j Where: k .62 NA.1 of PN-EN 1993-1-1 and n.3. However.moment factor from table B 3 of PN EN 1993-1-1.20. If the PLG parameter has been set to 1. The current implementation of EC3 BS in STAAD. χ and –buckling factor.j =y.3.Z Ed (+ Δ M .20(3) International Design Codes Manual — 331 . the maximum among the following ratios will be taken as being critical for Cl 6. The proposed implementation of the Polish NA will also use Annex B for Cl. l Cl.6.3.20. the program will not perform these checks. m = max M z . NA.Δ (I = y or z) 0 m = max M (+ Δ M y.61 6.20(2) and NA.20.(2): The following condition will be checked n/ χ and + C Where: n = N /N Ed y Rd y.3: 6.(2) and NA.i /W el. Ed )/M Z Rd. This implementation will provide for these additional checks as well. NA.pro uses the method in Annex B by default.1 – in case of class 3 and 4 sections. NA. χ LT m . przy czym w = W 0 0 i i pl. Ed )/M y.3 checks.1 + 0. The Polish NA also gives two additional simplified checks. Δ -correction factor (estimation of maximum reduction) and will be 0 worked out as: Δ = 0. 3.14 of PN EN 1993-1-1:2005). T PN EN 1993-1-1:2005 does not provide equations to calculate the elastic critical loads N cr.titled National Annex to Standard SS-EN 1993-1-1 . T − (Ncr.for use with Eurocode 3.53 of PN EN 1993-1-1:2005 are to be used to calculate the nondimensional slenderness λ .5 Singaporean National Annex to EC3 Adds values from the Singaporean National Annex . cr.4 .T these methods are used to evaluate the elastic critical loads for the Polish NA. TF = 2 io 2 2 2 iy +iz ( ) Ncr.52 and 6. The critical axial load for Torsional buckling is evaluated as: Ncr.Pro . 7D. Note: Refer to the basic code (EC3) for a description of these clauses. T = 2 GI t + io 1 π EI w I T2 2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively.4.4. However.Slenderness for torsional and torsional-flexural buckling Equations 6.If however PLG has been set to 0 (or not specified at all). The sections below refer to the corresponding clauses in the Singaporean-NA.1.59 of SS EN 1993-1-1:2005 as 0.F and N (refer 6. the program will ignore the last two checks in the list above. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr. H channel or box section to be used in equation 6.8 Clause 6. refer to the NCCI document SN001a-EN-EU. T 2 iy + i z2 2 io For details on these equations.T The NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and therefore cr.T. The NA document makes small changes to the base document. The following clauses are not implemented in STAAD.3.4(1) B – Slenderness for flexural buckling The SINGAPORE NA specifies the value of λc0 for I. STAAD. or EN 1993-1-1:2005. y + Ncr.TF cr. 7D. y + Ncr. to be used for torsional and torsional-flexural buckling checks. yN cr.2.3.Pro: Clause 6. T) 2 − 4Ncr.Pro does not 332 — STAAD. γ M0 = 1. this clause is ignored for the Singaporean National Annex. this clause is ignored for the Singaporean National Annex.3 and 6. Hence only doubly symmetric sections will be considered for this method..60 of SS EN 1993-11. Mcr. 7D. STAAD.Pro sets these values as the default values for the SS-NA (NA 7 is specified). & GM2 design parameters.5.Pro does not use this clause for design per EC-3. Clause 6. STAAD.1 Clause 6. GM1. Therefore.0 = 1. Note: You can change these values through the GM0. The Singaporean National Annex does not specify a particular method to calculate Mcr.0 M1 Resistance of members to instability. requires the calculation of the ‘Elastic Critical LT Buckling Moment’. γ M2 The design function in STAAD.2 –Elastic critical moment and imperfection factors for LTB checks The Singaporean NA recommends the use of Table 6.use this clause for design per EC-3.5.3.4 of NF EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks.4(2)B – Modification factor ‘kfl’ The value of the modification factor kfl to be used in equation 6.2 Clause 6.2. γ = 1. However. Hence the calculation of Mcr has been based on the following NCCI documents: SN003a-EN-EU – Elastic critical moment for Lateral torsional Buckling This document provides a method to calculate ‘Mcr’ specifically for doubly symmetric sections only. See "Design Parameters" on page 264 Note: If any of these parameters have been specified by the user as ‘0’.1 Resistance of cross sections to tension.Pro will ignore the specified value and use the default values as given above.2.1 – General The partial safety factors will use the following values: l l l Resistance of cross-sections. Therefore. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that have been dealt with in the Singaporean National Annex (hereafter referred to as SS-NA) and that are relevant to the proposed implementation are: 7D. The equation to evaluate Mcr is given in the NCCI as: International Design Codes Manual — 333 .3. The calculation of the LTB reduction factor X . 75 This NCCI considers three separate loading conditions: l l l C 1 1.57 Members with end moments Members with transverse loading Members with end moments and transverse loading.31 1.50 +0.05 2.25 -0.00 1. SN030a-EN-EU – Mono-symmetrical uniform members under bending and axial compression: This document provides a method to evaluate the elastic critical moment (Mcr) for uniform mono symmetric sections that are symmetric about the weak axis.Pro accounts for the loading condition and the bending moment diagram through the CMM parameter.6-Values of C for end 1 moment loading (for k=1) ψ +1.50 -0.00 +0. the elastic critical moment for ‘Tee-Sections’ will be evaluated using the method in this NCCI.77 2. The NCCI provides values for C1 and C2 for the different cases as given in the tables below: Table 7D.Pro .52 1.00 -0.14 1. 334 — STAAD.25 0.33 2. STAAD.M cr = C1 π EI (kL ) 2 2 k 2 I w k I + w (kL ) GI t π 2EI 2 2 + (C 2Zg) − C 2Zg C1 and C2 are factors that depend on the end conditions and the loading conditions of the member.75 +0. Hence. International Design Codes Manual — 335 . Hence this implementation will use this method only for TeeSections. The equation to evaluate M for mono symmetric sections is given as : cr M cr = C1 π EI z (k x L )2 2 kx k w 2 Iw I + (k x L )2GI T π 2EI z 2 + (C2zg − C 3z 1) − C2zg − C 3z 1 The factors C1. The user however can use the new ‘C1’. The default value of CMM is 0. C2 and C3 are dependent on the end conditions and loading criteria. STAAD. This NCCI does not however consider the “end moments and transverse loading” condition. ‘C2’ and ‘C3’ parameters to input the required values for C1. This implementation will consider C1. C2 and C3.Pro currently does not have a means to specify/identify a mono-symmetric built-up section. C2 and C3 to be used in calculating Mcr.Note: Though this method could also be applicable to mono-symmetric built-up sections. which considers the member as a pin ended member with UDL along its span. C2 and C3 as given in the tables below: The CMM parameter specified during design input will determine the values of C1. 0 l For rolled sections and hot-rolled & cold formed hollow sections: λLT. 7D. The use will be allowed to modify this value by using the ZG parameter.0 equation 6. The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section. CMN = 0.Pro obtains these values from Annex F of DD ENV version of 1993-1-1:1992.0)..Pro .5 or CMN = 0.Pro. Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero. STAAD. For members with partial or end fixities (i. Note: There is a separate method specified in the NCCI document “SN006a-EN-EU” to calculate Mcr for cantilever beams.Pro does not differentiate between rolled and welded sections and uses the default values in SS EN 1993-1-1 for λ and β.0 in the design input. For all cases that are not dealt with by the National Annex (or the NCCI documents) this implementation will use the method as per the DD ENV 1993-1-1:1992 code.4 β = 0.3 Clause 6. The values specified in the Singapore NA are: LT.75 l For welded sections: 336 — STAAD. Hence the above methods will be used only for members which are free to rotate on plan and which have no warping restraints (i. CMN = 1. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center.Note: If ‘MU’ as well as C1. A value of K = kw =1 is indicated by a value of CMN = 1.57 of SS EN 1993-1-1 for rolled and equivalent welded sections.e. C2 and C3.0). the program will ignore MU and use the user input values of C1. STAAD. STAAD. Again this document does not give any specific formulae to evaluate the coefficients. Hence.5.e. this implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992 – Annex F. By default.. if the load acts towards the shear center and is negative if it acts away from the shear center. this has not been implemented in STAAD. Both the NCCI documents mentioned above assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member ( k = kw = 1.Pro takes into account of the end conditions using the CMN parameter for EC3. C2 and C3 have been specified.7).3(1) – LTB for rolled sections or equivalent welded section The Singaporean NA specifies different values for the λ and β factors to be used in LT.2. The value of ‘zg’ is considered positive.3.0 = 0. 1 Angles (for moments in the major principle plane) All other hot-rolled sections Welded.2 β = 1.2.3.3(1) LT0 as follows: Table 7D. Table 6.3 to evaluate χ .2 and 6.3.3 — Calculation of LTB Reduction factor.3 on the other hand uses tables 6.3 to choose the buckling curves and imperfection factors. see 6.4 Clauses 6. 6.2.7-Buckling curves to use with SS-EN 1993-1-1:2005 Cross Section Limits Buckling Curve b c d d d h/b ≤ 2 2. 6.5 and 6.2. the program will LT consider Cl.3.”. LT Cl. Hence for these cases the new implementation will still use the method specified in the base code as per clause 6.3.3 (EN 1993-1-1:2005) both give equations to evaluate the LTB reduction factor χ to be used in eqn.1 and welded non-doubly symmetric sections.3 and 6.2..00 STAAD.2.2 to evaluate χ .Pro uses the buckling curves based on Table 6.3.5 of SS EN 1993-1-1:2005.4 to choose the buckling curve and the imperfection factors to be used for calculating χ .3.55 of SS EN 1993-1-1:2005. 6.0 < h/b ≤ 3. Cl 6. 6.2 and 6.1 c d Rolled doubly symmetric I and H sections and hot-finished hollow sections h/b ≤ 2 2.2.2. doubly symmetric sections and cold-formed hollow sections Note: This table does not specify which buckling curve is to be used in case of welded doubly symmetric sections with h/b ≥ 3.3.3.5.5 however only deals with “Rolled I Sections” and “Welded I Sections”.3.2.2..2.3. LT International Design Codes Manual — 337 . 6. For any case that is not dealt with by Cl. Cl.1 h/b > 3.2. χ as per Singaporean NA LT Clauses 6. for bending members of constant cross section the value of χ should be determined from. The Singaporean-NA provides the values for the terms λ and β factors given in clause 6. “Welded I Sections” and “Any other sections”. Hence in the implementation of EC3 LT (and the Singaporean Annex) in STAAD.0 < h/b ≤ 3.3.3. 6.4 specifies the choice of buckling curves for “Rolled I LT Sections”.2(2).Pro: by default the program will consider clause Cl.2 states “Unless otherwise specified.3.3. 7D.2 uses tables 6.2.λLT.0 = 0.2.3. Table 6. .2.2. 7D. The Singaporean-NA however. the program will use Cl.1. 6.e.2.3(2) – Modification factor. I sections with plates will be treated as built-up sections only if the section has been explicitly specified as a built-up section (i.0 in design input). the program will use the Table in the Singaporean NA for choosing a buckling curve for LTB checks (when the SS EN has been specified): l l l l l Rolled doubly symmetric I & H Sections Rolled doubly symmetric hollow sections (SHS.2 to evaluate χ . the program will use Cl. To evaluate the modification factor SS LT EN 1993-1-1:2005 uses a correction factor ‘kc’ given by Table 6.3. this implementation will choose the buckling curves from the Singaporean National Annex.3.Cl.3. 6. specifies that the correction factor ‘kc’ is to be obtained as below: 338 — STAAD. M .5 in SS EN 1993-1-1:2005 should be replaced with the table given in the NA (See section 4.0 (See section above) will be considered. Hence for all cases dealt with by the table in the Singaporean NA.3.3. CHS) Angle Sections Any other rolled section Welded doubly symmetric sections with h/b < 3.2 of BS EN 1993-1-1:2005.2 of SS EN 1993-1-1:2005. the program will use Cl.1 For the following cross sections. For all other cases of the CMN parameter values. 6.3 in the Singaporean National Annex states that Table 6. LT In any case. 6. RHS. (used to evaluate the non dimensional cr slenderness) will be evaluated as given above.5. only end restraint conditions corresponding to the CMN parameter=1. f. this implementation will use the method specified in Annex F of DD ENV 1993-1-1:1992. For all other cases.2. 6..3.e. NA parameter in the design input = 0). the elastic critical moment.2.2. Note: If a National Annex has not been specified (i. 6. Also.58 of SS EN 1993-1-1:2005 to evaluate the modification factor ‘f’ for the LTB reduction factor χ .3.3 of this document). SBLT parameter = 1. Since this implementation uses the NCCIs mentioned in the sections above. For any case that is not dealt with by the table in the Singaporean NA.6.Pro . For the following cross sections.6 in the code. for LTB checks The Singaporean NA specifies the use of Equation 6.5 Clause 6. the program will use the method given in Cl.3 of SS EN 1993-1-1:2005 to evaluate χ LT l Welded I & H Sections with h/b ≥ 3. the program will use Cl.2.3 only in the case of Rolled or welded I & H Sections.2.3.3. For any other type of cross section that is not dealt with by the National Annex or Cl. 1. (Cl. torsional slenderness (λT) and torsional-flexural slenderness (λTF) as given in Clauses 6.3 or λ from Cl 6. you can also input a custom value c of K by setting the design parameter KC to the desired value.0 for K .e..3 and 6.6 Clause 6. The proposed implementation of the Singaporean NA will also use Annex B for Cl. The current implementation does not account for the K factor and conservatively uses a reduction factor equal to 1. then the program will automatically calculate its value. design parameter CMN = 1.0).3. Hence for non-doubly symmetric sections the program will calculate the critical non-dimensional slenderness as: λ = the maximum of either λ from Cl 6. 7D. the slenderness about the weak axis (λy in STAAD) and the corresponding reduction factor χy should be taken as the values from the highest values of slenderness (λ) among the flexural buckling slenderness (λy). the c 1 program will use the NCCI documents as previously described. 0. kzy.4 of SS EN 1993-1-1:2005.3.7 or 0..3 checks. for non-doubly symmetric sections.2.2 of the Singaporean NA).61 and 6. As per the Singaporean NA. To evaluate C . However. If the KC parameter in the design c input is set to 0. International Design Codes Manual — 339 .6.62 of SS EN 1993-1-1:2005.3(5) – Interaction factors kyy.3. The NCCI document SN003a-EN-EU specifies the values of C1 to be used in table 3. These values are for an end restraint factor of k = 1 (i. This will cause the program to evaluate a value of C corresponding to the end conditions and the Bending 1 moment of the member and in turn calculate K as given in the NA. the Singaporean NA gives the option of using Annex B with some modifications as given in the NA. The program will use a default value of 1. Hence for all other values of CMN (i.e.3.3. NA-3.3. The Singaporean NA requires additional checks to be done to check for the maximum allowable values of λ and X to be used in equations 6. NcrTF).1 as shown below. The c program allows for the reduction factor based on the Singaporean-NA.1.5) this implementation will use the values of C from DD 1 ENV 1993-1-1:1992 Annex F.Kc = 1 / √C1 Where: C is to be obtained from the NCCI documents as previously described (See 1 "Clause 6.1.3. kyz.2 –Elastic critical moment and imperfection factors for LTB checks" on page 333). The current implementation of EC3 BS in STAAD.4 y T Where: λT = A ⋅f y N cr Ncr = min (NCrT.pro uses the method in Annex B by default. However for non-doubly symmetric sections.1.5. and kzz The Singaporean NA recommends the methods in either Annex A or Annex B of SS-EN 1993-11 to calculate these interaction factors. T 2 iy + i z2 2 io For details on these equations.T.3 checks.5.Slenderness for torsional and torsional-flexural buckling" on page 340. T = 2 GI t + io 1 π EI w I T2 2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively. to be used for torsional and torsional-flexural T buckling checks. Therefore. H. however. 7D.7. TF = 2 io 2 2 2 iy +iz ( ) Ncr.3. refer to the NCCI document SN001a-EN-EU.3. RHS or CHS sections.14 of SS EN 1993-1-1:2005).52 and 6. T − (Ncr. y + Ncr.7 Clause 6.F cr.1. The program will only consider Channel Sections and Tee.sections while working out the critical torsional and Flexural Torsional buckling loads as per Cl 6. the program uses the method specified in the NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” to calculate these.4 . Clause NA 3.1. the elastic properties will be used for the purposes of 6. Hence.4. In the current implementation this is done as per cl 4. CrT crTF Therefore. yN cr.3.T.F cr.Pro . y + Ncr.T included in this implementation of the Singaporean NA. it will be treated as a class 3 section for the purposes of this clause”. λ .2 of the Singaporean NA also requires that “Where the section is not an I Section or a hollow section and is a class1 or class 2 section. the NCCI cr. SHS. The SS EN 1993-1-1:2005 does not provide equations to calculate the elastic critical loads N and N (refer 6.The Singaporean NA or EC3 does not.4 . This proposed implementation will still use the same method for single and double angle sections to evaluate the slenderness.T document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and hence will to be cr.1.3. specify a method to evaluate N or N . Note: The Singaporean National Annex or EC3 does not deal with angle sections in specific and hence this implementation will use the method used in the current EC3 implementation to deal with slenderness of angle sections. See "Clause 6.Slenderness for torsional and torsional-flexural buckling Equations 6. 340 — STAAD. T) 2 − 4Ncr. The critical axial load for Torsional buckling is evaluated as: Ncr.10 of BS 5950. for all Class 1 or Class 2 cross sections that are not I.53 of SS EN 1993-1-1:2005 are to be used to calculate the nondimensional slenderness parameter. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr.3. Pro does not use this clause for design per EC-3.7D.2. The clauses/sections in EN 1993-1-1:2005 (hereafter referred to as EC-3) that have been dealt with in the Belgian National Annex (hereafter referred to as NBN-NA) and that are relevant to the proposed implementation are: 7D. However. Therefore. this clause is ignored for the Belgian National Annex. Note: You can change these values through the GM0. any National Annex is allowed to override these default values. 6. Clause 6.. See "Design Parameters" on page 264 Note: If any of these parameters are specified as 0.Pro sets these values as the default values for the PN-NA (NA 8 is specified). γ = 1. Note: Refer to the basic code (EC3) for a description of these clauses. & GM2 design parameters.6 Belgian National Annex to EC3 Adds values from the Belgian National Annex—titled National Annex to Standard NBN-EN 1993-1-1—for use with Eurocode 3. this clause is ignored for the Belgian National Annex.0 = 1. γ M2 The design function in STAAD.4(1) B – Slenderness for flexural buckling STAAD.25 Resistance of cross sections to tension. International Design Codes Manual — 341 . 0) and use the default values as given above.Pro does not use this clause for design per EC-3.Pro will ignore the user specified value (i.3. and γ . The sections below refer to the corresponding clauses in the NBN-NA. These factors are γ .6.e. STAAD.2. GM1. The following clauses are not implemented in STAAD.3. The NA document makes small changes to the base document. γ M0 = 1. or EN 1993-1-1:2005. Therefore.1 Clause 6. γ . EN 1993 provides default values for M0 M1 M2 these factors. The partial safety factors will use the following values for the Belgian National Annex: l l l Resistance of cross-sections.1(1) – General EN 1993-1-1:2005 specifies the use of the partial safety factors to be used in for design as given in Cl.0 M1 Resistance of members to instability.1 of the code.4(2)B – Modification factor ‘kfl’ STAAD.Pro: Clause 6. Pro accounts for the loading condition and the bending moment diagram through the CMM parameter.77 . Clause 3. This NBN-NA considers three separate loading conditions: l l l Members with end moments Members with transverse loading Members with end moments and transverse loading.Pro. For any other type of section that is not dealt with by Annex D.Pro .3 and 6.e. requires the calculation of the Elastic Critical LT Buckling Moment.2 Clause 6.1. 1 2 Table 1 deals with the condition of a simply supported member with end moments and the value of C is determined by the end moment ratio (Refer to the NA for details). The NBN-NA gives a method to calculate M in Annex D. for cr uniform mono symmetric sections that are symmetric about the weak axis.60 The value of C2 is determined based on the Table 2 of the Annex. The Annex 1 2 provides values for C & C for the different cases as given in Table1 and Table 2 of the Annex. M . however. Hence for this 342 — STAAD. Mono-symmetric sections with symmetry about their weak axis Annex D of NBN-NA also provides a method to evaluate the elastic critical moment.6.04ψ + 0. only deals with the calculation of M for doubly cr symmetric sections and mono symmetric sections that are symmetric about the minor axis (i. The calculation of the LTB reduction factor χ . Annex D. which is cr cr used by STAAD.27ψ2 ≤ 2. STAAD.4 of EN 1993-1-1:2005 to calculate the imperfection factors for Lateral Torsional Buckling (LTB) checks.2 –Elastic critical moment and imperfection factors for LTB checks The NBN-NA recommends the use of Table 6. M .2. Tee sections).Pro uses the method and tables given in Annex F of DD ENV 1993-1-1:1992: Doubly symmetric sections Annex D of NBN-NA provides equation used to calculate M specifically for doubly cr symmetric sections: M cr = C1 π EI (kL ) 2 2 k 2 I w k I + w (kL ) GI t π 2EI 2 2 + (C 2Zg) − C 2Zg C & C are factors that depend on the end conditions and the loading conditions.3.7D.2 of 1 the National Annex however gives a formula to calculate C as: 1 C1 = 1. based on the loading and end conditions as specified using the CMM parameter. STAAD. and C are dependent on the end conditions and loading criteria.Pro currently does not have a means to specify/identify a mono-symmetric built-up section. The equation to evaluate M for mono symmetric sections is given as: cr M cr = C1 π EI z (k x L )2 2 kx k w 2 Iw I + (k x L )2GI T π EI z 2 2 + (C2zg − C 3z 1) − C2zg − C 3z 1 The factors C . C . C2 and C3 as given in the tables below: International Design Codes Manual — 343 . This 1 2 3 implementation will consider C1.implementation the elastic critical moment for Tee-Sections is evaluated using the method in this Annex. Hence this implementation will use this method only for TeeSections. STAAD. Note: Though this method could also be applicable to mono-symmetric built-up sections. 000 0.5 ψ = -1/2 1.0 2.0 0.Pro .37 1.0 0.06 2.000 1.000 1.55 -ψ 0.5 ψ = +1/2 1.125 f 0.Table 7D.0 0.35 1.5 2.8-Critical moment coefficients for singly symmetric sections with end moments End Moments and Support Conditions Bending moment diagram k z Value of coefficients C 1 C ψ ≤ f 0 3 ψ > f 0 ψ = +1 1.5 ψ = -1/4 1.31 1.000 1.05 1.42 0.650 1.77 1.000 0.125 0.000 1.5 ψ = +1/4 1.5 2.00 1.850 1.850 f ψ = -1 1.7ψ f 344 — STAAD.017 1.7ψ 0.0 0.950 f ψ = -3/4 1.0 0.000 1.45 0.35 -ψ -ψ f ψ = +3/4 1.2ψ 0.60 1.15 2.5 ψ=0 1.0 0.0 2.000 1.5 1.019 1.77 -ψ 0.000 1.5 2.3 1.60 -ψ f 0.60 1.45 0.0 f 0.000 1.000 1.14 1.19 1.000 f 0.52 1.86 2. 5 1.338 0..31 0.0 0. STAAD.539 0.e.5 0.e. For all cases that are not dealt with by the National Annex (or the NCCI documents) this implementation will use the method as per the DD ENV 1993-1-1:1992 code.0 1.5 or CMN = 0.562 0. STAAD. the program will ignore MU and use the user input values of C1.Note: According to Section 3(1): C2 zg = 0 Table 7D.0 1. C2 and C3 have been specified. By default. the program will assume that the load acts towards the shear center at a distance equal to (Depth of section/2) from the shear center.5 0. this implementation will fall back on to the method and coefficients in DD ENV 1993-1-1:1992 – Annex F. which considers the member as a pin ended member with uniformly distributed load (UDL) along its span.35 1. C2 and C3. The user however can use the new ‘C1’.95 The CMM parameter specified during design input will determine the values of C1.97 0.48 0.0).04 0.. The International Design Codes Manual — 345 .Pro obtains these values from Annex F of DD ENV version of 1993-1-1:1992.478 0.9-Value of coefficients Load and support conditions Bending moment diagram k z Value of coefficients C 1 C 2 C 3 1. A value of K = kw =1 is indicated by a value of CMN = 1.525 0.0). Note: If ‘MU’ as well as C1. The term ‘zg’ in the equation to calculate Mcr refers to the distance between the point of application of load on the cross section in relation to the shear center of the cross section.59 0. The value of ‘zg’ is considered positive. C2 and C3 to be used in calculating Mcr.Pro takes into account of the end conditions using the CMN parameter for EC3. For members with partial or end fixities (i. Hence the above methods will be used only for members which are free to rotate on plan and which have no warping restraints (i.7).0 in the design input. This NCCI does not however consider the “end moments and transverse loading” condition.45 0. Both the NCCI documents mentioned above assume that the member under consideration is free to rotate on plan and that there are no warping restraints for the member ( k = kw = 1.12 0.411 0.05 1. and C3. C2. CMN = 0. CMN = 1. ‘C2’ and ‘C3’ parameters to input the required values for C1.42 0.36 1. The default value of CMM is 0. if the load acts towards the shear center and is negative if it acts away from the shear center. 6.75 The program evaluates which factors to use based on the CMN parameter.5. χ as per Belgium NA LT Clauses 6.3.3.3 to evaluate χ .2. then the first set of λ and β values is used.use will be allowed to modify this value by using the ZG parameter.3. “Welded I Sections” and “Any other sections”.3.3(1) – LTB for rolled sections or equivalent welded section The NBN-NA recommends the use of the values specified in EN 1993-1-1 for the LTB factors λ and β.3 — Calculation of LTB Reduction factor.3 to choose the buckling curves and imperfection factors. If M is determined by ignoring the lateral restraints.55 of NBN-EN 1993-1-1:2005.5 however only deals with “Rolled I Sections” and “Welded I Sections”. For any case that is not dealt with by Cl.6. 7D.2.3. LT 7D.2.2.2. LT0 LT0 These factors are then applied to equation 6.2 states “Unless otherwise specified.0 2. Cl.3.4 and β = 0. see 6.4 to choose the buckling curve and the imperfection factors to be used for calculating χ . If CMN = 1.2. Specifying a value of ZG = 0 in the design input would indicate that the load acts exactly at the shear center of the section so that the term ‘zg’ in the equation will have a value of zero. Table 6.3.2 to evaluate χ . Note: The program does not consider the case of cantilevers. If CMN = 0.2. Hence in the implementation of EC3 LT (and the Belgian Annex) in STAAD.2 uses tables 6. LT 6. 6.2 and 6.”. LT Cl.0 (default).4 Clauses 6. Cl 6.3(1) – LTB for rolled sections or 346 — STAAD. for bending members of constant cross section the value of χ should be determined from. (See "Clause 6.. However it gives two different sets of values for λ & β based on two different LT0 LT0 conditions as give below: 1. 6. 6.3.Pro .5 and 6.2.3.3.3 on the other hand uses tables 6. Table 6.3 Clause 6. the program will consider Cl..3. If M is determined by considering the properties of the gross cross section and the cr lateral restraints.3 and 6. the following values are used: λ LT0 =0. then the program assumes the restraints are ignored and the second set of values is used for λ and β.2.2.3.2 and β = 1. the following values are used: cr λ LT0 =0.2 and 6.3 in the Belgian National Annex gives equations to evaluate the imperfection factors to be used for various section types.6. 6.3.2.2.2. LT Cl.3.3. 6.4 specifies the choice of buckling curves for “Rolled I LT Sections”.3 (EN 1993-1-1:2005) both give equations to evaluate the LTB reduction factor χ to be used in eqn.57 of NBN-EN to evaluate the Lateral Torsional Buckling reduction factor χ .Pro: by default the program will consider clause Cl.3.2. 6. I sections with plates will be treated as built-up sections only if the section has been explicitly specified as a built-up section (i.equivalent welded section" on page 346 ).e the value of CMM parameter specified). the elastic critical moment..2 to evaluate χ .0 in design input). However the user can also input a custom value of ‘kc’ by setting the design parameter ‘KC’ to the desired value.2.e.e.3. This will cause the program to work out ‘kc’ from table 6.2.2.2.3.Mcr.2 of NBN-EN 1993-11:2005. Since this implementation uses the NCCIs mentioned in the sections above. This can be specified using the MTH design parameter (See "Design Parameters" on page 264). l For CMM = 7 the program will choose the value of ‘kc’ to be either 0.3. 6. The program uses a default value of 1. NA parameter in the design input = 0)..3 only in the case of Rolled or welded I & H Sections.6 of NBN EN 1993-1-1:2005.3(1) – LTB for rolled sections or equivalent welded section" on page 346 ) will be considered.2.3(2) – Modification factor. 6. For all other cases of the CMN parameter values. You can override the default behavior and specify the clause that is to be used for LTB checks. (used to evaluate the non dimensional slenderness) will be evaluated as given above.5 Clause 6. For CMM = 8 the program will choose the value of ‘kc’ to be either 0. Note: If a National Annex has not been specified (i.91 based on the end moment ratio.6.3. the program will use Cl.3. this implementation will use the method specified in Annex F of DD ENV 1993-1-1:1992. mod ≤ 1 λ LT 2 International Design Codes Manual — 347 .2. For all other cases. Hence the proposed implementation will use the existing functionality to work out the correction factor ‘kc’ to be used in the modification factor f. only end restraint conditions corresponding to the CMN parameter=1.0 (See "Clause 6. for LTB checks The Belgian NA specifies that the modification factor is to be obtained as per the default method given in EC-3.3.90 or 0. f. this implementation will use Cl 6.3.6.82 based on the end moment ratio. Hence for all cases dealt with by the equations in the NBN-NA.0 for ‘kc’. Also.2. the program will use Cl. l An additional check will also be performed as given below: χLT .3. LT In any case. This will correspond to the end conditions and the bending moment of the member (i. the program will use Cl. SBLT parameter = 1.3 to evaluate χ .77 or 0. LT For any other type of cross section that is not dealt with by the National Annex or Cl. 7D. The user can also get the program to calculate the value of ‘kc’ automatically by setting the value of the ‘KC’ parameter in the design input to 0. F cr.3. refer to the NCCI document SN001a-EN-EU.52 and 6. The critical axial load for Torsional-Flexural buckling is evaluated as: Ncr.Pro .6. The NA also mentions that torsional flexural buckling needs to be taken into account in case of mono symmetric sections.3. The NBN-EN 1993-1-1:2005 does not provide equations to calculate the elastic critical loads N and N (refer 6.4.7 Clause 6. T = 1 2 io GI t + π EI w I T2 2 Where: 2 2 2 2 2 io = iy + iz + yo + zo i and i are the radius of gyration about the Y-Y (weak axis) and Z-Z (strong y z axis) respectively. the NCCI cr. The program will only consider Channel Sections and Tee. λ . kzy.1.3(5) – Interaction factors kyy. The NA also recommends a lower limit as given below for the term C in table A. Torsional flexural buckling will need to be taken into account based on the method given in the NCCI document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes”.53 of NBN-EN 1993-1-1:2005 are to be used to calculate the nondimensional slenderness parameter.6 Clause 6. Therefore.Slenderness for torsional and torsional-flexural buckling Equations 6. 0 ≥ 1 − N Ed N cr . y + Ncr. The critical axial load for Torsional buckling is evaluated as: Ncr. and kzz The NBN-NA recommends the equations in Annex A of NBN-EN 1993-1-1 to calculate these interaction factors.T.T included in this implementation of the Belgian NA.3.1. y + Ncr. T − (Ncr.14 of SS EN 1993-1-1:2005).0 Annex A: Cmi.i 7D.sections while working out the critical torsional and Flexural Torsional buckling loads as per Cl 6.3.7D.2 of mi. 348 — STAAD. kyz. to be used for torsional and torsional-flexural T buckling checks.4 . See section below for details.F cr.T document “SN001a-EN-EU: Critical axial load for torsional and flexural torsional buckling modes” provides methods to calculate the N and N factors and hence will to be cr. TF = 2 io 2 iy +iz ( 2 2 ) Ncr. yN cr.6.T. T) 2 − 4Ncr. T 2 iy + i z2 io 2 For details on these equations. International Design Codes Manual — 349 . 7E.7E.Part 1. There is no Eurocodespecific timber section database / library consisting of pre-defined shapes for analysis or for design. A detailed description of the design process along with its underlying concepts and assumptions is available in the specification document. The longitudinal axis of the member is defined as x and joins the start joint of the member to the end with the same positive direction. The primary considerations in ultimate limit state design are strength and stability. Appropriate load and resistance factors are used so that a uniform reliability is achieved for all timber structures under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. the most economic section is selected on the basis of the least weight criteria as augmented by the designer in specification of allowable member depths. 7E. defines the principal cross-section axes in reverse to that of STAAD. Timber Design Per EC 5: Part 1-1 STAAD.1: General-Common rules and rules for buildings.Pro is capable of performing timber design based on the European code EC5 Part 1-1 Eurocode 5: Design of timber structures .1 Axes convention in STAAD and EC5 STAAD defines the major axis of the cross-section as zz and the minor axis as yy. or other such parameters. The design philosophy of this specification is based on the concept of limit state design. stability and serviceability. The feature of member selection is thus not applicable to this code. Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use. The code checking portion of the program checks whether code requirements for each selected section are met and identifies the governing criteria. Accordingly. Two major categories of limit-state are recognized . desired section type.ultimate and serviceability. Design of members per EC5 Part 1-1 requires the STAAD Euro Design Codes SELECT Code Pack.1. Design per EC5 is limited to the prismatic. EC5. rectangular shapes only. The following sections describe the salient features of the STAAD implementation of EC 5. while that in serviceability is deflection. members are proportioned to resist the design loads without exceeding the limit states of strength. Both of these axes definitions follow the orthogonal right hand rule.1 General Comments Principles of Limit States Design of Timber Structures are used as specified in the code. In the STAAD implementation. but the longitudinal axis is defined in the same way. however. m For “Solid Timber”. Timber Design Per EC 5: Part 1-1 Figure 7E. perpendicular to the direction of grain alignment.SCL).2004. For “Solid Timber”.Pro. γ m – Partial factor for Material Property values. Km – Factor considering re-distribution of bending stress in cross section. D.3 and 3.2 and 1. this factor should be taken into account. = 1. For members. possibility of splitting and degree of compressive deformation. B. For members. 350 — STAAD. whose maximum c/s dimension is less than the reference width in tension the characteristic strength in tension (ft0k) is to be increased by the factor Kh.3) for such solid timber is incorporated in the software. Kh – Size Factor.1.2(3) of EC 5.7E.5 of EC-5-2004 in this regard.1.1 . the value of γ C. subjected to tension. Please refer clause 6.4 for the value of Kh for Glued laminated timber and Laminated veneer lumber respectively. for rectangular solid timber with a characteristic timber density ρ ≤ 700 kg/m 3 the reference depth in bending or the reference width k (maximum cross-sectional dimension) is 150 mm.Pro .3 is incorporated in the program. whose depth is less than reference depth in bending. For members.3 of EC-5-2004.Axis conventions per STAAD and Eurocode 5 STAAD EC5 7E. E.1 of EC-5-2004. Please refer clause numbers 3. the values are incorporated in the program. User may override the value. the characteristic strength in bending (fmk) is to be increased by the factor Kh. Reference Table 2. subjected to compression. The value of Kh = Minimum of {(150/h) 0. KC90 – Factor taking into account the load configuration. As per clause 3. Kmod – Modification factor taking into account of Load-duration (LDC) and Moisture-content (Service Class .2 Determination of Factors A. subjected to bending. Reference Table 3. Default value of 1 is used in STAAD. this factor is taken into account for stress checking.Pro internally using the guidelines of clause 6.1. For rectangular section the value of Km is 0.6 of EC-5-2004 in this regard. User may override the value.1. and this value is incorporated in STAAD.7.8 of EC-5-2004. Please refer clause 6.For members.Pro. subjected to torsional force. International Design Codes Manual — 351 . This factor is determined by STAAD. subjected to bending. For members. design torsional stress should be less than equal design shear strength multiplied by the factor Kshape. F. Kshape – Factor depending on shape of cross section. perpendicular to the grain alignment. Design compressive stress parallel to grain alignment.l E G z rel. The default value is 1. Design shear strength about yy axis. Design compressive strength . Design compressive stress perpendicular to grain alignment. Design bending strength .perpendicular to the grain alignment. Design torsional stress.Pro . Fifth percentile value of shear modulus parallel to grain.z y rel. t90d c0d c90d mzd myd vd S F F F F F F tor_d t0d t90d c0d c90d mzd myd vd F RATIO l .parallel to the grain alignment.7E.05 0. Design bending stress about yy axis.05 Slenderness ratios corresponding to bending about zz axis. Torsional moment of inertia.2 Analysis Methodology Table 7E. Width and depth of beam. Design tensile stress perpendicular (at 90 degrees) to grain alignment. the following characteristic strength values are required to compute the other related characteristic values. Permissible ratio of stresses as input using the RATIO parameter. 352 — STAAD. Design tensile strength . Design bending strength . Design tensile strength . h Equations for Characteristic Values of Timber Species as per Annex-A of EN 338:2003 The following equations were used to determine the characteristic values: For a particular Timber Strength Class (TSC).1-EC5 Nomenclature Symbol S S S S S S S t0d Description Design tensile stress parallel (at zero degree) to grain alignment. Design shear stress. I I I f z y tor mk b. Timber Design Per EC 5: Part 1-1 7E. Second moment of area about the strong z-axis.y 0.about yy-axis.parallel to the grain alignment. Second moment of area about the weak y-axis.l l . Slenderness ratios corresponding to bending about yy axis. Design bending stress about zz axis. Fifth percentile value of modulus of elasticity parallel to grain.about zz-axis. Characteristic bending strength. Design compressive strength . However. 8. Mean Modulus of Elasticity in bending – E iii.4.ρ SI No.k k k f E v. the values obtained from the provided equations are treated as actual and is used by the program.0.mean 0.1 Design values of Characteristic Strength As per clause 2. Bending Strength – f m. Tensile Strength parallel to grain Tensile Strength perpendicular to grain Compressive Strength parallel to grain Compressive Strength perpendicular to grain Shear Strength Modulus of Elasticity parallel to grain Mean Modulus of Elasticity perpendicular to grain Mean Shear Modulus Shear Modulus E f f t. 5.84* E 0.mean mean 0.45 0.k t.0.i.k f f ) 0.k c.8 and 0. may differ with the tabulated values in Table-1 of EN 338:2003. mean ii.2*f m.k 0. in all such cases.mean 0. 7. 4. Density .90.k 0.2. International Design Codes Manual — 353 .007*r m.mean 0.8)} (0. 9.05 /16 The values of the characteristic strengths computed using the above equations. k Property Symbol Wood Type Softwood Hardwood (C) (D) 1. This depends on several factors such as cross sectional properties. 7E.0015*r )} 5 * (f 0.6 * f m. 2.6 and (0.k 0.05 0. Design values of a strength property shall be calculated as: Xd = K mod·(Xk /γm) Where: X is design value of strength property d k X characteristic value of strength property γm is partial factor for material properties. as the values of Table-1 are based on these equations.67* E E 0.mean 90.mean /16 G E 0.1. 3. 6.0015*r k c. The member resistance in timber structure is calculated in STAAD according to the procedures outlined in EC5.90.k Minimum of {0.05 /30 E /15 G E 0.k Minimum of {3. 7E. (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO 7E.11 and 6. The methodology adopted in STAAD for calculating the member resistance is explained here.2. Timber Design Per EC 5: Part 1-1 different load and material factors. the following formula should be checked per Equation 6. timber strength class.1 of EC-5 2004: St0d /Ft0d ≤ RATIO If the direction of applied axial tension is perpendicular to the direction of timber grain alignment. the following formula should be checked per Equation 6.5 Check for Shear stresses Horizontal stresses are calculated and checked against allowable values per Equation 6.2.Pro . load duration class. Note: In STAAD z-z axis is the strong axis. service class and so on.3 of EC-5 2004: St0d /(Ft0d ·Kc90) ≤ RATIO 7E.2 of EC-5 2004: Sc0d /Fc0d ≤ RATIO If the direction of applied axial compression is perpendicular to the direction of timber grain alignment. the following formula should be checked per Equation 6.2 Check for Tension stresses If the direction of applied axial tension is parallel to the direction of timber grain alignment. the following formula should be checked: St90d /Ft90d ≤ RATIO 7E.7E.2. the following conditions should be satisfied per Equations 6.4 Check for Bending stresses If members are under bending stresses.14 of EC-5 2004: Stor_d /(Kshape·Ftor_d ) ≤ RATIO 354 — STAAD.2.6 Check for Torsional stresses Members subjected to torsional stress should satisfy Equation 6.13 of EC-5 2004: Svd /Fvd ≤ RATIO 7E.12 of EC-5 2004.2.3 Check for Compression stresses If the direction of applied axial compression is parallel to the direction of timber grain alignment. 3 the following conditions should be rel.y satisfied: (Sc0d /Fc0d )2 + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO (Sc0d /Fc0d )2 + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO In other cases. the conditions in Equations 6.23 and 6.05 )1/2 If both λ and λ are less than or equal to 0.7 Check for combined Bending and Axial tension Members subjected to combined action of bending and axial tension stress should satisfy Equations 6.05 )1/2 λrel.19 and 6. (St0d /Ft0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO (St0d /Ft0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO 7E.2.y = λy /π·(Sc0k /E0. Equations 6. Column Stability check The relative slenderness ratios should be calculated per Equations 6. International Design Codes Manual — 355 . λrel.24 of EC-5 2004 should be satisfied. Note: In STAAD z-z axis is the strong axis.z = λz/π·(Sc0k /E0. (Sc0d /Fc0d )2 + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO (Sc0d /Fc0d )2 + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO 7E. Note: In STAAD z-z axis is the strong axis.7E.9 Stability check A.2.22 of EC-5 2004.z rel.17 and 6.2.21 and 6.18 of EC-5 2004: Note: In STAAD z-z axis is the strong axis.20 of EC-5 2004 should be satisfied: Note: In STAAD z-z axis is the strong axis.8 Check for combined Bending and axial Compression If members are subjected to bending and axial compression stress. crit)1/2 For hardwood.0. the stresses should satisfy Equation 6. 356 — STAAD.3 Design Parameters Design parameters communicate specific design decisions to the program.05 ·Iy ·G0.crit = 0.m when 0. the stresses should satisfy Equation 6.m ≤ 0. use Equation 6.Pro .56 .m)2 when 1.05 ·Itor)1/2 /(lef·W z) For softwood.. to Equations 6.05 /(h·lef) 7E.4 < λrel.5·[1 + βc·(λrel. 0.crit = π·(E0. the user may have to change some or all of the parameter default values.z .z)2 ] Ky = 0.32 and 6. the new setting must be compatible with the active “unit” specification.3) + (λrel.31 of EC-5 2004: Sm. c B.3) + (λrel.35 of EC-5 2004 (ref.y )2 ]1/2 } Kz = 0.28 of EC-5 2004): Kcz = 1/{Kz + [(Kz)2 .m λrel.y .0.y )2 ] The value of β incorporated in the software is the one for solid timber (i.(λrel.34 of the same): [Smzd /(Kcrit·Fmzd )]2 + Sc0d /(Kcz·Fc0d ) ≤ RATIO Where: Kcrit = 1. Depending on the model being designed.0.z)2 ]1/2 } Kcy = 1/{Ky + [(Kzy )2 . Some parameters are unit dependent and when altered.30 of EC-5 2004: Sm.7E.25 through 6. use Equation 6.5·[1 + βc·(λrel.75 < λrel.4 Kcrit = 1/( λrel.2).0 when λrel. They are set to default values to begin with and may be altered to suite the particular structure.75 Kcrit = 1. Timber Design Per EC 5: Part 1-1 Sc0d /(Kcz·Fc0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO Sc0d /(Kcy·Fc0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO Where (Equations 6.33 of EC-5 2004: Smzd /(Kcrit·Fmzd ) ≤ RATIO Where a combination of moment about the strong z-axis and compressive force exists.75·λrel. Beam Stability check If members are subjected to only a moment about the strong axis z.e.78·b2 ·E0.m ≤ 1.(λrel.m = (fmk /Sm. 6. Table 7E.1. if both the parameters SERV and DFF are present with specific values.1. DJ2 End node number for a physical member under consideration for Deflection Check. See section 5.6. deflection check will be performed.0 Angle of inclination of load to the grain alignment.1 of the Technical Reference Manual.2.0 = Load parallel to grain 90.1. In this case.2) DJ1 Start node number for a physical member under consideration for Deflection Check.51.0 = Load Perpendicular to grain DFF None “Deflection Length” / Max. please refer Cl.6. International Design Codes Manual — 357 . Cl.1. its value stays at that specified number until it is specified again.2-Timber Design EC 5: Part 1-1 Parameters Parameter Name CODE Default Value Description Must be specified as TIMBER EC5 Design Code to follow. This is the way STAAD works for all codes.2 (Table 7.1.7. Cl.6. (Ref. Cl. Cl.4) 0.3.Note: Once a parameter is specified. ALPHA 0. For appropriate range of values. Allowable Net Final Local Deflection. Cl. depending on load-position.0 (Member Length) Effective Length Factor for Local-y-axis. contact length at support locations etc.6. Timber Design Per EC 5: Part 1-1 Parameter Name KC90 Default Value 1.0 ≤ KC90 ≤ 4.1. KY 1. possibility of splitting and degree of compressive deformation.7E. KZ 1. Cl. (Ref.6. Cl. user may specify any value within the range.3.1).0 Other than the default value.6. for the computation of the relative slenderness ratios. for the computation of the relative slenderness ratios. Effective Length Factor for Local-z-axis.0 (Member Length) 358 — STAAD. Required only for MTYP value of 1 (Beam).3. (Ref.0 Description Factor taking into account the load configuration. Table 6.2).0 (Member Length) Effective Length Factor to check Lateral Torsional Buckling (Ref. The user will put the appropriate value from the Table 6. l KLEF 1.1.Pro .2). (Ref.5-(2)) l Range: 1. Factor multiplied by the span of the beam and depends on the support conditions and load configurations. loaddispersion. 0 = Long term action 3.0 = Class 2.2).6. Moisture content ≤ 12% 2.1.0 = Beam Member 2.0 = Medium term action 4. required to get the K-MOD value from Table – 3.0 = Permanent action 2. RATIO SCL 1.3.0 = Not defined.0 = Instantaneous action MTYP 0 Member Type: Beam/Column. Service Class (Ref.0 = Column Member This information is required to find which stability check will be performed as per the Cl 6. Cl.3) 1. 1. Cl.3.2.0 = Class 3.3 according to the Member Type.6.1.3) 0. Moisture content > 20% International Design Codes Manual — 359 .2.0 = Class 1. both clauses are checked (Default) 1.0 = Short term action 5.3.3. Cl.0 3 Permissible ratio of actual to allowable value.1. (Ref. Cl.2. Moisture content ≤ 20% 3.Parameter Name LDC Default Value 1 Description Load Duration Class (Ref. 16 = D50. l Hardwood: 13 = D30. 7 = C27.4. 1 .A. moisture content ≤ 20% 360 — STAAD.0 = Print the design output at the intermediate detail level 3. Reference EN338 – 2003) l Softwood: 1 = C14. 3 = C18. 4 = C20. 5 = C22. 11 = C45.7E. 15 = D40. This TSC definition will calculate the corresponding characteristic strength values using the equations as given in BS-EN-338. Design the member for the ultimate limit state.0 = Print the design output at the minimal detail level 2. 6 = C24. 10 = C40. Timber Design Per EC 5: Part 1-1 Parameter Name TRACK Default Value 0 Description Degree/Level of Details of design output results.Pro .Timber Column A Timber Column of length 1. 1. 2 = C16.4 Verification Problems 7E. 17 = D60. Material properties: Timber class: C24 Service classes: Class 2.0 kN.0 = Print the design output that the maximum detail level TSC 6 (C24) Timber Strength Class (Ref. 18 = D70. 8 = C30. 7E. having c/s dimension of 73 mm X 198 mm.0 meter. 12 = C50.1 Verification Problem No. Annex . 9 = C35. is subjected to an axial compressive force of 50. 14 = D35. 1.EN 338:2003] λrel.4.1 Material factors γm = 1.67·E0.739)1/2 = 0.92 N/mm² [Cl 2.1031 kN/m2 As timber grade is C24 (i.92 = 0.3 fc0k = 21. y z Radius of gyration of cross section about z-axis r = 57 mm.0 [Cl.mean = 0.30 … from table 2.268 < 1. Rectangular cross section.739 kN/m2 [Annex A.1(1)P] Cross section loads: Fx = 50. h = 198 mm.05 = 0.Load duration classes: Medium-term Cross section properties: Length of the member is 1 m.00)/1. Effective cross sectional area A = 14. 6.46N/mm² < 12. Radius of gyration of cross section about y-axis r = 21 mm.298 International Design Codes Manual — 361 .62 E0.mean = 1.770x105 mm³ z Section modulus of cross section about y-axis: W = 1.. Soft Wood) E0.00/0.80·21.z = λz/π·(fc0k /E0.759x105 mm³ y Solution Characteristic material properties for timber: Modification factor Kmod = 0.80 …from table 3.000 kN Compression parallel to the grain: Sc0d = (1000xFx )/A = (1000x50.54/π(21.4.454 mm².30 = 12. Section modulus of cross section about z-axis: W = 4.000)/14454 = 3.00 N/mm² Fc0d = (Kmod·fc0k )/γm = (0.(1)P] Check for Slenderness: Slenderness ratios: λz = (1000/57) = 17.46 / 12.e.92N/mm² (Fc0d ) The ratio of actual compressive stress to allowable compressive strength: Sc0d /Fc0d = 3. b = 73 mm.54 λy = (1000/21) = 47.05 )1/2 = 17. 0.541 Ky = 0.878 Kcz = 1/{Kz + [(Kz)2 .y .0.0 + 0.809)2 ] = 0.z)2 ] = 0.008 Kcy = 1/{Ky + [(Kzy )2 .z .Pro Difference 0. following conditions should be satisfied: Sc0d /(Kcz·Fc0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO Sc0d /(Kcy·Fc0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO Where: Kz = 0.266 Sc0d /(Kcy·Fc0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) = 3.0 + 0.326 Hence the critical ratio is 0.0. Timber Design Per EC 5: Part 1-1 λrel.92) + 0.0 + 0.298)2 ] = 0.327 none Input File The following file is included AS C:\SProV8i\STAAD\Examp\Eur\EC5 ver 1. λ rel.0 and the section is safe. Sc0d /(Kcz·Fc0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) = 3.3) + (0.70.326 < 1.46/(1.298)2 ]1/2 }= 1. 6.0. so actual bending stress is zero.std.298 . The member is subjected to Compression only.3.739)1/2 = 0.3-EC 5: Part 1-1 Verification Problem 1 Criteria Critical Ratio (Cl.3) + (0. STAAD SPACE INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 0 0 0.y = λy /π·(fc0k /E0.878)2 .0 = 0.008·12.05 )1/2 = 47.3.2(0.(λrel.0 + 0.268 + 0. 2 1.809)2 ]1/2 } = 0.00/0.62/π(21.0 = 0. DEFINE MATERIAL START ISOTROPIC WOOD 362 — STAAD.3) + (λrel.541 + [(0.326 + + 0.5·[1 + βc·(λrel.3) + (λrel.809 .(λrel.809 Since.50·[1 + 0.5·[1 + βc·(λrel.0 = 0. MEMBER INCIDENCES 1 1 2.92) + 0.326 0.(0.0 0 0.0 = 0.46 /(0.y )2 ]1/2 } = 1/{0.y is greater than 0.541)2 . Comparison Table 7E.z)2 ]1/2 } = 1/{0.(0.50·[1 + 0.y )2 ] = 0.Pro .7E.2) Reference STAAD.2(0.878 + [(0.820·12.820 For Rectangular cross section Km = 0. 00 C 0.15 DENSITY 0.00231749 ALPHA 5.073 YD = 0.00 0.E 1.Pro CODE CHECKING .KN MEMBER TABLE LOADING/ LOCATION ======================================================================= 1 PRIS ZD = 0.198 PASS CL.5E-006 END DEFINE MATERIAL CONSTANTS MATERIAL WOOD MEMB 1 MEMBER PROPERTY 1 PRIS YD 0.0000 METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ FX MY RATIO/ MZ International Design Codes Manual — 363 .6.(EC5 ) *********************** ALL UNITS ARE .198 ZD 0.3.327 1 50.00 0.2 0.073 SUPPORTS 1 FIXED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 JOINT LOAD 2 FX -50 PERFORM ANALYSIS PARAMETER CODE TIMBER EC5 ALPHA 0 ALL LDC 3 ALL SCL 2 ALL TSC 6 ALL TRACK 2 ALL CHECK CODE ALL FINISH Output The member checking part of the output file: STAAD.10316E+007 POISSON 0. 00 | | LEZ = 1.00 | | | | ALLOWABLE STRESSES: (NEW MMS) | | FBY = 14. Material properties: Timber Strength Class: C24 Service classes: Class 2.m about its major and minor axes respectively. 2 A Timber Column of length 1.00 IZ = 0.759x105 mm³ y 364 — STAAD.000 fbz = 0.770x105 mm³ z Section modulus of cross section about y-axis: W = 1. Rectangular cross section. Radius of gyration of cross section about y-axis r = 21 mm. h = 198 mm. is subjected to an axial compressive force of 5.4.Pro . Design the member for the ultimate limit state. Section modulus of cross section about z-axis: W = 4.0 kN and moments of 2.7E.459 | |-------------------------------------------------------------------------| 7E. y z Radius of gyration of cross section about z-axis r = 57 mm. Effective cross sectional area A = 14454 mm².769 FBZ = 14. b = 73 mm.000 | | fc = 3. having c/s dimension of 73 mm X 198 mm.859 | | ACTUAL STRESSES : (NEW MMS) | | fby = 0.2 Verification Problem No. moisture content <=20% Load duration: Medium-term Cross section properties: Length of the member is 1 m.769 | | FC = 12.01 IY = 0.00 LEY = 1.0 kN.m and 1.0 kN. Timber Design Per EC 5: Part 1-1 |-------------------------------------------------------------------------| | AX = 0.0 meter. 62 λrel.00 N/mm² Fmyd = Kmod·fmyk /γm = (0. λ rel.y .30 = 14.878 + [(0.80x24.298 λrel.008 Kcy = 1/{Ky + [(Kzy )2 .000 kN·m Check for Slenderness: Slenderness ratios: λz = (1000/57) = 17.000 kN Mz = 2.00)/1.1(1)P] fmyk = 24.2(0.809)2 ]1/2 } = 0.00/7370)1/2 = 0.3) + (0.54 λy = (1000/21) = 47.y )2 ] = 0.3) + (0.y = λy /π·(fc0k /E0.298)2 ] = 0.70.809)2 ] = 0.62/π(21.0.(0.5·[1 + βc·(λrel.30 … from table 2.y )2 ]1/2 } = 1/{0.0.3 fc0k = 21.00)/1.05 = 7370 N/mm2 Fc0d = (Kmod·fc0k )/γm = (0.05 )1/2 = 47.00/7370)1/2 = 0. Sc0d = (1000·Fx /A) = (1000·5.z = λz/π·(fc0k /E0.77N/mm² Cross section loads: Fx = 5.Solution Characteristic material properties for timber: Modification factor Kmod = 0.5·[1 + βc·(λrel.77N/mm² fmzk = 24.80x24.y is greater than 0.878)2 .05 )1/2 = 17.54/π(21.0.000)/14454 = 0.809 .2.30 = 14.0.298 .z .820 For Rectangular cross section Km = 0.00 N/mm² Fmzd = Kmod·fmzk /γm = (0.00 N/mm² E0.80 …from table 3.3]: Sc0d /(Kcz·Fc0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) ≤ RATIO Sc0d /(Kcy·Fc0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) ≤ RATIO Where: Kz = 0.92 N/mm² [Cl 2.3) + (λrel.541 + [(0.(0.000 kN·m My = 1.3) + (λrel.35 N/mm² International Design Codes Manual — 365 .80·21.50·[1 + 0.3.30 = 12.z)2 ] = 0.298)2 ]1/2 }= 1.50·[1 + 0.809 Since.4.1 Material factors γm = 1.z)2 ]1/2 } = 1/{0.00)/1.(λrel.878 Kcz = 1/{Kz + [(Kz)2 .541 Ky = 0.(λrel.3. following conditions should be satisfied [Cl 6.2(0.541)2 . 198 = 0.7E.Pro .616 < 1.283 + 0.616 0.70(5. 6.Pro Difference 0.15 DENSITY 0.616 none Input File The following file is included AS C:\SProV8i\STAAD\Examp\Eur\EC5 ver 2.198 ZD 0.69/14. Timber Design Per EC 5: Part 1-1 Smzd = (106 ·Mz)/W z = (106 ·2.10316E+007 POISSON 0.35/(1.5E-006 END DEFINE MATERIAL CONSTANTS MATERIAL WOOD MEMB 1 MEMBER PROPERTY 1 PRIS YD 0.70(4.073 SUPPORTS 366 — STAAD.000)/(1.69/14.385 + 0.77 + 0.820·12. MEMBER INCIDENCES 1 1 2.759x105 ) = 5. DEFINE MATERIAL START ISOTROPIC WOOD E 1.77) = 0. Comparison Table 7E.033 + 0.69 N/mm² Combined stress ratio: Sc0d /(Kcz·Fc0d ) + (Smzd /Fmzd ) + Km·(Smyd /Fmyd ) = 0.4-EC 5: Part 1-1 Verification Problem 2 Criteria Critical Ratio (Cl. STAAD SPACE INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 0 0 0.00231749 ALPHA 5.616 Hence the critical ratio is 0.027 + 0. 2 0 1 0.0 and the section is safe.266 Sc0d /(Kcy·Fc0d ) + Km·(Smzd /Fmzd ) + (Smyd /Fmyd ) = 0.19/14.008·12.92) + 0.000)/(4.77 = 0.77) + 5.3.2) Reference STAAD.92) + 4.770x105 ) = 4.19 N/mm² Smyd = (106 ·My )/W y = (106 ·1.19/14.35 /(0.std.269 = 0. KN MEMBER TABLE LOADING/ LOCATION ======================================================================= 1 PRIS ZD = 0.00 | | LEZ = 1.00 LEY = 1.769 FBZ = 14.Pro CODE CHECKING .00 -2.0 PERFORM ANALYSIS PARAMETER CODE TIMBER EC5 ALPHA 0 ALL LDC 3 ALL SCL 2 ALL TSC 6 ALL TRACK 2 ALL CHECK CODE ALL FINISH Output The member checking part of the output file: STAAD.0000 |-------------------------------------------------------------------------| | AX = 0.1 FIXED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 JOINT LOAD 2 FY -5.0 MZ 2.6.073 YD = 0.2 0.00 IZ = 0.198 PASS CL.3.(EC5 ) *********************** ALL UNITS ARE .00 C 1.00 0.0 MX 1.00 | | | | ALLOWABLE STRESSES: (NEW MMS) | | FBY = 14.769 | METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ FX MY RATIO/ MZ International Design Codes Manual — 367 .616 1 5.01 IY = 0. 859 | | ACTUAL STRESSES : (NEW MMS) | | fby = 5.686 fbz = 4.193 | | fc = 0.346 | |-------------------------------------------------------------------------| | 368 — STAAD.7E. Timber Design Per EC 5: Part 1-1 FC = 12.Pro . Section 8 Finnish Codes International Design Codes Manual — 369 . 370 — STAAD.Pro . B4 Concrete structures). Finnish Codes . Design of members per B4 requires the STAAD N.Pro is capable of performing concrete design based on the Finnish code B4 Suomen rakentamismääräyskokoelma.8A. International Design Codes Manual — 371 . Eurozone Design Codes SELECT Code Pack.Concrete Design per B4 STAAD. B4 Betonirakenteet (National Building Code of Finland. 372 — STAAD.Pro . 1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to the B4 code. DRYCIR 100 EFACE 0. See section 5. CLEAR 25 mm Clearance of reinforcement measured from concrete surface to closest bar perimeter. Note: Both SFACE & EFACE must be positive numbers. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. Bracing parameter for design: 0. ACTAGE BRACE 70 0.0 Face of support location at end of beam. Column unbraced in either direction. Note: Once a parameter is specified. its value stays at that specified number until it is specified again. One-way plate or column braced in only the local Z direction. The following table contains a complete list of available parameters with their default values. Design Code to follow. This is the way STAAD works for all codes.52.8A. Default values of commonly used parameters for conventional design practice have been chosen as the basis.1-Finnish Concrete Design per B4 Parameters Parameter Name CODE Default Value Description Must be specified as FINNISH. International Design Codes Manual — 373 . in percent. in years. 2. in current units. Table 8A. Drying exposure. 3. Beam or column braced in both directions 1.2 of the Technical Reference Manual. in current units. Column braced in only the local Y direction.0 Actual age of concrete. Maximum size permitted for main reinforcement bar. Minimum size permitted for main reinforcement bar. Column bar arrangement 1. NA — Aggressive 3. 7 days 32 Age when loaded. 500 N/mm 2 Yield strength of main reinforcing steel. LA — Least aggressive 2.Pro . moy factor moz factor nmag factor 0 40 1 Reinforcement angle. in days. 3. Two faced distribution about major axis.Parameter Name ELY Default Value 1. in degrees. Member length factor about local Z direction for column design.0 ENVIR 2 FC FYMAIN LAGE MAX MAIN MINMAIN 35 N/mm 2 Compressive strength of concrete. 2. in percent.0 Description Member length factor about local Y direction for column design. Faced symmetric distribution 10 MOY MOZ NMAG REIANG RELHUM RFACE 374 — STAAD. Four longitudinal bars. 4. Environment class 1. Two faced distribution about minor axis. MA — Very aggressive ELZ 1. Relative humidity. STIRANG STIRDIA TORANG TRACK 90 10 mm 45 10 Stirrup angle.B Strength of Structures. Stirrup diameter Torsion angle. Slab — Plane stress design. Liite 3: Kansallinen liite standardiin SFS-EN 206-1 (The National Building Code of Finland . They are set to default values to begin with and may be altered to suite the particular structure. 8A. B7 Steel Structures Guidelines). Beam — Ultimate limit state and Service limit state design & Slab — Two-way plate design 11.Steel Design per B7 STAAD. in degrees. 8A. B4 Betonirakenteet. Beam — Ultimate limit state design only 20. Slab — Simplified membrane design. Track parameter to control output detail 10. Note: Both SFACE & EFACE must be positive numbers. Beam — Ultimate limit state and Service limit state design with tension stiffening. Design of members per B7 requires the STAAD N.2 Design Parameters Design parameters communicate specific design decisions to the program.Pro is capable of performing steel design based on the Finnish code B7 Suomen rakentamismääräyskokoelma.Parameter Name SFACE Default Value 0 Description Distance from the start node of the beam to face of support for shear design. 12. Eurozone Design Codes SELECT Code Pack. in degrees. Finnish Codes . 30. International Design Codes Manual — 375 . 2-Design Parameters for Finnish B7 Steel design code Parameter Name CODE Default Value none Description Must be specified as B7.Pro . M vi BZ 1. Design Code to follow. for strong axis buckling (z-z) (NOTE: BZ > 0.0 BY 1.0 Maximum allowable depth of steel section.8A. b. Finnish Codes .0 Parameter BEAM 1. β.0 CB 1.0 Buckling length coefficient. fy [N/mm2 ] Ratio of material factor / resistance factor Permissible ratio of the actual to allowable stresses. c. CY CZ DMAX Default see NS 3472 100.0 1.0 = Sidesway in local y-axis weak axis β =SSY M SSY 0. FYLD MF RATIO Yield strength of steel. a0.0 [cm] 235 1.0 CMZ 1. See section 5. Represent the a.0 = No sidesway. Used to calculate the ideal buckling moments.Steel Design per B7 Table 8A. DMIN Minimum allowable depth of steel section. β calculated.0) Lateral buckling coefficient.0 376 — STAAD. and up to 8 points at each section. a about local z-axis (strong axis).1 of the Technical Reference Manual.0 ALL tells the program to calculate von Mises at 13 sections along each member.0) Buckling length coefficient. BEAM 0. > 0. Y. 0. d curve. β for weak axis buckling (y-y) (NOTE: BY > 0.5 n for built up section in connection with lateral buckling Buckling curve coefficient.) Note: Must be set to 1. (Depending on what kind of shape is used.48.0 [cm] 0. β calculated. when given with negative value. define an inside pressure in pipe members.0 = Print all critical member stresses. International Design Codes Manual — 377 . ref.e.Parameter Name SSZ Default Value 0. printed by member number 9. NS app. Distance between fork supports or between effective side supports for the beam The parameter CMY will.0 Description 0..2. UNL Member length Effective length for lateral buckling calculations (specify buckling length).0 Specifies the level of detail in the output.0 = Print von Mises stresses 3. i.0 = No sidesway. 5.2. > 0.0 = Sidesway in local y-axis weak axis β M TRACK 0. design values 2. The pressure corresponds to given water depth in meters.0 = Member results. The parameter CB defines the φ value with respect to calculation of the ideal lateral buckling moment for single symmetric wide flange profiles. 0.0 = Suppress critical member stresses 1.0 = Print detailed report each member. 378 — STAAD.Pro . Section 9 French Codes International Design Codes Manual — 379 . Pro .380 — STAAD. Parameters Parameter Default Name Value CODE BAEL Description Must be specified as BAEL.A.E.2 of the Technical Reference Manual. have been used for simplicity. French Codes .0 Note: Both SFACE and EFACE are input as positive numbers. STAAD will calculate the required reinforcing to resist the various input loads.Pro is capable of performing concrete design based on the French code BAEL 1991 E Béton Armé aux États Limites: Regles techniques de conception et de calcul des ouvrages et constructions en beton arme.A. of commonly used numbers in conventional design practice.A. suivant la methode des etats limites (Reinforced Concrete Limit States: Technical rules for design and costing and reinforced concrete. Design Code to follow. Depth of concrete member. Table 9A. Design of members per BAEL 1991 E requires the STAAD Eurozone Design Codes SELECT Code Pack.1 contains a complete list of available parameters and their default values. DEPTH EFACE *0. These parameters not only act as a method to input required data for code calculations but give the engineer control over the actual design process. CLEAR * 20 mm YD Clearance of reinforcing bar.9A. Table 7A.L. See section 5.L STAAD. Face of Support Location at end of beam.1-French Concrete Design B.L. according to the method of limit states). Value is automatically set to 20 mm for C35 and higher. International Design Codes Manual — 381 . 9A.E. Given the width and depth (or diameter for circular columns) of a section. Default values. This value defaults to YD as provided under MEMBER PROPERTIES.Concrete Design per B. its value stays at that specified number until it is specified again. Note: Once a parameter is specified.52.1 Design Parameters The program contains a number of parameters which are needed to perform design per B. This is the way STAAD works for all codes.E. Width of the concrete member. Here. Critical Moment will not be printed out with beam design report. after solving for the joint displacements of the structure. FYSEC Yield Stress for secondary reinforcing steel. Minimum main reinforcement bar size. when the PDELTA ANALYSIS command is used. 9A. calculates the additional moments induced in the 382 — STAAD.Pro .0 NSE CTION 10 TRACK 0.2 Slenderness Effects and Analysis Consideration STAAD provides the user two methods of accounting for the slenderness effect in the analysis and design of concrete members.60mm). The first method is a procedure which takes into account second order effects. Face of support location at start of beam. A value of 1. A factor by which the design moments will be magnified.use MEMBER OFFSET for bending. STAAD accounts for the secondary moments. French Codes . MAX MAIN Maximum main reinforcement bar size. Number of equally-spaced sections to be considered in finding critical moments for beam design. Minimum secondary reinforcement bar size. FYMAIN Yield Stress for main reinforcing steel.Concrete Design per B. (8mm . MINMAIN 8 mm MINSEC 8 mm MMAG 1. STAAD.L Parameter Default Name Value FC * 30 N/ mm 2 * 300 N/mm 2 * 300 N/mm 2 50 mm Description Concrete Yield Stress. (8mm 60mm). This value defaults to ZD as provided under MEMBER PROPERTIES.9A.0 will mean a print out.0 WIDTH ZD * These values must be provided in the units currently being used for input.0 SFACE *0.A. (8mm 60mm). Only considers shear . due to axial loads and deflections.E. stirrup sizes are calculated with proper spacing. 9A. From the critical moment values. the program will calculate values from YD and ZD. In the above input. Example of Input Data for Beam Design: UNIT NEWTON MMS START CONCRETE DESIGN CODE BAEL FYMAIN 415 ALL FYSEC 415 ALL FC 35 ALL CLEAR 25 MEM 2 TO 6 International Design Codes Manual — 383 . by using PDELTA ANALYSIS. with only depth and no width provided. The stirrups are assumed to be U-shaped for beams with no torsion.3 Member Dimensions Concrete members that are to be designed by STAAD must have certain section properties input under the MEMBER PROPERTIES command. Here the user approximates the additional moment by supplying a factor by which moments will be multiplied before beginning member design. unless that number is redefined with the NSECTION parameter. From these values.structure. Therefore. The total number of sections considered is twelve. For both types of beam action. the first set of members are rectangular (450 mm depth and 300 mm width) and the second set of members. all active beam loadings are scanned to create moment and shear envelopes. member forces are calculated which will require no user modification before beginning member design. Note that area (AX) is not provided for these members. 11 13 PR YD 300. Shear design includes critical shear values plus torsional moments. The following example demonstrates the required input: UNIT MM MEMBER PROPERTIES 1 3 TO 7 9 PRISM YD 450 ZD 300. with cut-off lengths calculated to include required development length. but if not provided. If shear areas (AY & AZ) are to be considered in analysis. the user may provide them along with YD and ZD. and closed hoops for beams subject to torsion.4 Beam Design Beam design includes both flexure and shear. 9A. will be assumed to be circular with a 300 mm diameter. and locate critical sections. the required positive and negative bar pattern is developed. Also note that moments of inertia may be provided. The second method by which STAAD allows the user to account for the slenderness effect is through user supplied moment magnification factors. section 6.9A.L MAXMAIN 40 MEMB 2 TO 6 SFACE 100 MEMB 7 TO 9 EFACE 100 MEMB 7 TO 9 TRACK 1. To design a slab or wall.5 Column Design Columns are designed for axial force and biaxial moments at the ends. The parameters FYMAIN. Other parameters mentioned in Table 7A. This may cause slightly conservative results in some cases.A.0 MEMB 2 TO 6 TRACK 2. These moments are obtained from the element force output (see Section 3. and circular sections.1 are not applicable to slab design. The command specifications are in accordance with Chapter II.8 of the Technical Reference Manual).40. rectangular. Example of Input Data for Column Design: UNIT NEWTON MMS START CONCRETE DESIGN CODE BAEL FYMAIN 415 ALL FC 35 ALL CLEAR 25 MEMB 2 TO 6 MMAG 1. The reinforcement required to resist Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist My moment is denoted as transverse reinforcement. it must be modeled using finite elements. That means the total number of bars will always be a multiple of four (4).Concrete Design per B.6 Slab/Wall Design Slab and walls are designed per BAEL 1983 specifications.5 MEMB 4 5 MAXMAIN 40 MEMB 2 TO 6 DESIGN COLUMN 2 TO 6 END CONCRETE DESIGN 9A. FC. All active loadings are tested to calculate reinforcement.Pro .1 are relevant to slab design. French Codes .E. Column design is done for square. 384 — STAAD. Elements are designed for the moments Mx and My.0 MEMB 7 TO 9 DESIGN BEAM 2 TO 9 END CONCRETE DESIGN 9A. and CLEAR listed in Table 7A. The loading which produces maximum reinforcement is called the critical load. For rectangular and square sections. the reinforcement is always assumed to be equally distributed on each side. 1 .Element moments: Longitudinal (L) and Transverse (T) Example of Input Data for Slab/Wall Design: UNIT NEWTON MMS START CONCRETE DESIGN CODE BAEL FYMAIN 415 ALL FC 25 ALL CLEAR 40 ALL DESIGN ELEMENT 15 TO 20 END CONCRETE DESIGN International Design Codes Manual — 385 .Figure 9A. 386 — STAAD.Pro . 2 Basis of Methodology The "Design Rules for Structural Steelwork (Revision 80)" permits the usage of elastic analysis.1 General Comments The design philosophy embodied in this specification is based on the concept of limit state design.3 Member Capacities The member strengths are calculated in STAAD according to the procedures outlined in section 4 of this specification. 9B." A detailed description of the design process. The next few sections describe the salient features of STAAD implementation of "Design Rules for Structural Steelwork. 9B. Two major categories of limit-states are recognized: ultimate and serviceability. The primary considerations in ultimate limit state design are strength and stability. Slenderness calculations are made and overall geometric stability is checked for all members. 1977 edition Centre Technique Industriel de la Construction Metallique (Industrial Technical Center of Metal Construction) publication entitled Design Rules for Structural Steelwork . in STAAD.Steel Design per the French Code STAAD. is available in the specification document. along with its underlying concepts and assumptions. Structures are designed and proportioned according to the limit states of which they would become unfit for their intended use. French Codes . shear and bending in calculating section capacities. members are proportioned to resist the design loads without exceeding the limit states of strength.9B. In the STAAD implementation.Pro is capable of performing steel design based on the French code CM66. Thus. Axial compression buckling and lateral torsional buckling are taken into consideration for calculation of axial compression resistance and flexural resistance of members. Note that the program automatically considers co-existence of axial force. linear elastic analysis method is used to obtain the forces and moments in the members. as augmented by the designer in specification of allowable member depths. the most economic section is selected on the basis of the least weight criteria. Design of members per CM66 requires the STAAD NEurozone Design Codes SELECT Code Pack. However. Appropriate load and resistance factors are used so that uniform reliability is achieved for all steel structures under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. or other related parameters. Accordingly. International Design Codes Manual — 387 . 9B. stability and serviceability. that in serviceability is deflection. desired section type. The code checking portion of the program verifies that code requirements for each selected section are met and also identifies the governing criteria. strength and stability considerations are based on the principles of plastic behavior. These parameters communicate design decisions from the engineer to the program. See section 5. some or all of these parameter values may be changed to exactly model the physical structure.4 Combined Axial Force and Bending The procedures of sections 4. 9B.0 = design only for end moments and those at locations specified by SECTION command. For axial compression capacity. Depending on the particular design requirements.1) must be used to specify the unsupported length of the compression flange for a laterally unsupported member. its value stays at that specified number until it is specified again.55 and 5. Note: Once a parameter is specified. thus allowing the engineer to control the design process to suit an application's specific needs. Appropriate interaction equations are used and the governing criterion is determined.0 0. Note that this length is also referred to as twisting length. 9B. and use maximum Mz for design. French Codes . 388 — STAAD. The parameter UNL (see Table 7B.1 of the Technical Reference Manual.48.6.32 are implemented for interaction of axial forces and bending. procedures of section 4.2 are followed.5 Design Parameters The design parameters outlined in Table 7B. The default parameter values have been selected as frequently used numbers for conventional design. formulas of section 5. This is the way STAAD works for all codes.5 and 4. 1. Table 9B.Pro .3 are used.22 of the specification. BEAM 0.9B.0 = calculate moments at tenth points long the beam.Steel Design per the French Code For axial tension capacity.1-French Steel Design Parameters Parameter Name CODE Default Value Description FRENCH Design Code to follow. Lateral torsional buckling is considered in calculating ultimate twisting moment per section 5.1 may be used to control the design procedure. Moment capacities about both axes are calculated using the procedures of sections 4. this is the major axis. K value for axial compression buckling about local Z-axis.0 to 1. Length to calculate slenderness ratio about Y-axis for axial compression. table 5. K value for axial compression buckling about local Y-axis.56 "Deflection Length" divided by the Maximum allowable local deflection C2 1. DMIN 0. Length to calculate slenderness ratio about Z-axis for axial compression. usual range from 0.Parameter Name C1 Default Value Description 1.0 DFF None (Mandatory for deflection check) Start Joint of member DJ1 Joint No.0 MPa 1.21 in the calculation of M(D). Usually.71 to 4. Yield strength of steel. this is the minor axis. the critical twisting moment and as shown in CM 66 Addendum 80. the critical twisting moment and as shown in CM 66 Addendum 80.0 LY Member Length Member Length LZ International Design Codes Manual — 389 . FYLD KY 250.0 Parameter used in clause 5. table 5. denoting end point for calculation of "Deflection Length" (See Note 1) Maximum allowable depth (used in member selection).10 Parameter used in clause 5.21 in the calculation of M(D). Usually.0 cm. usual range from 0.0 cm.0 KZ 1. denoting starting point for calculation of "Deflection Length" (See Note 1) Joint No. Minimum allowable depth (used in member selection). DJ2 End Joint of member DMAX 100. Unsupported length of compression flange for calculating moment resistance. French Codes .48. e.g.0 Same as above provided as a fraction of member length.0 SAME* 0. then the selected section will be an equal angle and vice versa for unequal angles. Refer to Section 2. 9B.0 = Try only those sections with a similar name as original. even if there are HEM’s in the same table.5 of the Technical Reference Manual for general information on Code Checking.0 = Print all design strengths. Permissible ratio of actual load effect and design strength.Steel Design per the French Code Parameter Name NSF Default Value Description 1.Pro . UNF 1. UNL Member Length *For angles. 390 — STAAD. RATIO 1.6 Code Checking and Member Selection Both code checking and member selection options are available in the STAAD.2 of the Technical Reference Manual for details the specification of the Code Checking command..0 TRACK 0. if the original is an HEA 100.0 = Try every section of the same type as original 1. 80).0 Net section factor for tension members. 0.Pro implementation of CM 66 (Revn. Controls the sections to try during a SELECT process.9B. Refer to Section 5. if the original section is an equal angle. then only HEA sections will be selected.0 0. 1.0 = Suppress printing of all design strengths. double angle. l l These operations may be repeated by the user any number of times depending upon the design requirements. Currently STAAD supports steel design of wide flange.48. The following is a detailed description of printed items: PC = Member Compression Capacity TR = Member Tension Capacity MUZ = Member Moment Capacity (about z-axis) MUY = Member Moment Capacity (about y-axis) VPZ = Member Shear Capacity (z-axis) VPY = Member Shear Capacity (y-axis) STAAD contains a broad set of facilities for designing structural members as individual components of an analyzed structure. Note: COND CRITIQUE refers to the section of the CM 66 (Revn. The operations to perform a design are: l Specify the members and the load cases to be considered in the design. double channel. Specify design parameter values. angle.7 Tabulated Results of Steel Design Results of code checking and member selection are presented in the output file in a tabular format. M.Refer to Section 2.3 of the Technical Reference Manual for details the specification of the Member Selection command. These facilities may be used selectively in accordance with the requirements of the design problem. S. The member design facilities provide the user with the ability to carry out a number of different design operations. composite beams and code checking of prismatic properties. channel.0. Refer to Section 5.6 of the Technical Reference Manual for general information on Member Selection. If the TRACK parameter is set to 1. if different from the default values. beams with cover plate. HP shapes. Specify whether to perform code checking or member selection. calculated member capacities will be printed. 80) specification which governed the design. 9B. Sample Input data for Steel Design: UNIT METER PARAMETER CODE FRENCH International Design Codes Manual — 391 . These properties are stored in a database file.1 IPE Shapes These shapes are designated in the following way. A complete listing of the sections available in the built-in steel section library may be obtained by using the tools of the graphical user interface.Steel Design per the French Code NSF 0.Pro .9 ALL TRACK 1. Following are the descriptions of different types of sections. 3 5 TA ST HEA120A 7 10 TA ST HEM140 13 14 TA ST HEB100 9B.85 ALL UNL 10.2 HE shapes HE shapes are specified as follows. 10 15 TA ST IPE140 20 TO 30 TA ST IPEA120 33 36 TO 46 BY 2 TA ST IPER180 9B.2 MEMBER 3 4 RATIO 0.8 Built-in French Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. If called for.0 ALL CHECK CODE ALL 9B.0 MEMBER 7 KY 1. 9B.8.3 IPN Shapes The designation for the IPN shapes is similar to that for the IPE shapes.9B. shear deformation is always considered for these members.8.8. 25 TO 35 TA ST IPN200 23 56 TA ST IPN380 392 — STAAD. the properties are also used for member design. An example of the member property specification in an input file is provided at the end of this section. French Codes . Since the shear areas are built into these tables. 8. For example.6 Double U Channels Back to back double channels. 9B. The standard angle section is specified as follows: 16 20 TA ST L30X30X2. with or without a spacing between them. The letter D in front of the section name will specify a double channel.7 Angles Two types of specification may be used to describe an angle. member 11 is a back-to-back double channel UAP150 with no spacing in between.9B.8. are available. This specification may be used when the local Z axis corresponds to the z-z axis specified in Chapter 2. 11 TA D UAP150 17 TA D UAP250A SP 0.7mm.8.5 In the above set of commands.8.5 International Design Codes Manual — 393 . but instead by referring to the I beam shapes from which they are cut. 17 21 TA RA L25X25X4 22 24 TA RA L100X100X6. 1 TO 5 TA ST UAP100 6 TO 10 TA ST UPN220 11 TO 15 TA ST UPN240A 16 TO 20 TA ST UAP250A 9B. Member 17 is a double channel UAP250A with a spacing of 0. If the local Y axis corresponds to the z-z axis. 1 5 TA T IPE140 2 8 TA T HEM120 9B.4 T Shapes Tee sections are not input by their actual designations.5 U Channels Shown below is the syntax for assigning 4 different names of channel sections.5 length units between the channels.7 The above section signifies an angle with legs of length 30mm and a leg thickness of 2. type specification "RA" (reverse angle) should be used instead of ST. 9 Tubes (Rectangular or Square Hollow Sections) Section names of tubes. 9B. the ".0mm. Members 66 and 73 are tubes with a depth of 200mm.0 TH 0.0 WT 6. having a wall thickness of 12. Only code checking.0" in the thickness is part of the section name. will be performed for TUBE sections specified in this way.10 Pipes (Circular Hollow Sections) To designate circular hollow sections.Steel Design per the French Code Note that if the leg thickness is a round number such as 4. 33 35 TA SD L30X20X4 SP 0.75 9B. 64 78 TA ST TUB50252.0. For example.0 Members 64 and 78 are tubes with a depth of 50mm. French Codes . The following example illustrates the designation.Pro . 64 and 78 are pipes 219.5 length units. just like angles. width of 100mm and a wall thickness of 8. no member selection. either SD or LD will serve the purpose.1mm in dia. the decimal part is not part of the section name. 8 TO 28 TA ST PIP422. Members 3.7mm. width of 6 length units.6mm.5 is a tube that has a depth of 8 length units. use PIP followed by numerical value of the diameter and thickness of the section in mm omitting the decimal portion of the value provided for the diameter. in front of the angle size.7 66 73 TA ST TUB2001008. and a wall thickness of 0. In case of an equal angle.5 Members 8 to 28 are pipes 42.8.5 SP 0. consist of the depth. 6 TA ST TUBE DT 8. only the number 4 appears in the section name. respectively. having a wall thickness of 2.6 37 39 TA LD L80X40X6 43 TO 47 TA LD L80X80X6. width and wall thickness as shown below.9B.5mm. 394 — STAAD. 9B.6 3 64 78 TA ST PIP21912.8. Tubes can also be input by their dimensions instead of by their table designations.8.4mm in dia. Unlike angles.8 Double Angles Short leg back-to-back or long leg back-to-back double angles can be specified by means of input of the words SD or LD. width of 25mm and a wall thickness of 2. 0 ID 20. of 20 length units.8.5 * ANGLES 7 TA ST L30X30X2. Only code checking. no member selection will be performed if this type of specification is used.0 specifies a pipe with outside dia.LONG LEGS BACK * TO BACK 10 TA LD L80X40X6 SP 0.Circular hollow sections may also be provided by specifying the outside and inside diameters of the section. 1 TO 9 TA ST PIPE OD 25.11 Example SAMPLE FILE CONTAINING FRENCH SHAPES STAAD SPACE UNIT METER KN JOINT COORD 1 0 0 0 15 140 0 0 MEMB INCI 1 1 2 14 UNIT CM MEMBER PROPERTIES FRENCH * IPE SHAPES 1 TA ST IPEA120 * IPN SHAPES 2 TA ST IPN380 *HE SHAPES 3 TA ST HEA200 * T SHAPES 4 TA T HEM120 * U CHANNELS 5 TA ST UAP100 * DOUBLE U CHANNELS 6 TA D UAP150 SP 0.7 * REVERSE ANGLES 8 TA RA L25X25X4 * DOUBLE ANGLES .SHORT LEGS BACK * TO BACK 9 TA SD L30X20X4 SP 0.75 International Design Codes Manual — 395 . 9B.25 * DOUBLE ANGLES . For example. of 25 length units and inside dia. 6 * PIPES (CIRCULAR HOLLOW SECTIONS) 14 TA ST PIPE OD 25.7 * TUBES (RECTANGULAR OR SQUARE * HOLLOW SECTIONS) 12 TA ST TUBE DT 8.0 TH 0.0 PRINT MEMB PROP FINI 396 — STAAD.Steel Design per the French Code * TUBES (RECTANGULAR OR SQUARE * HOLLOW SECTIONS) 11 TA ST TUB50252.5 * PIPES (CIRCULAR HOLLOW SECTIONS) 13 TA ST PIP422. French Codes .Pro .0 ID 20.9B.0 WT 6. Section 10 German Codes International Design Codes Manual — 397 . 398 — STAAD.Pro . ZD 250.4.1 Section Types for Concrete Design The following types of cross sections for concrete members can be designed. the details regarding placement of the reinforcement on the cross section are also reported in the output.3/17. It is absolutely imperative that the user not provide the cross section area (AX) as an input. Slab design is also available and this follows the requirements of Baumann. with only depth and no width provided. the first set of members are rectangular (450 mm depth and 250 mm width) and the second set of members.4 which is used as the basis for commonly used design charts considering e/d and sk/d for conditions where the slenderness moment exceeds 70. Design for a member involves calculation of the amount of reinforcement required for the member. The following example shows the required input: UNIT MM MEMBER PROPERTY 1 3 TO 7 9 PRISM YD 450.Concrete Design Per DIN 1045 STAAD. reinforced and prestressed concrete structures. and Circular) 10A. Design of members per DIN 1045 requires the STAAD Eurozone Design Codes SELECT Code Pack.Pro is capable of performing concrete design based on the German code DIN 10451:2001-07 Plain. will be assumed to be circular with 350 mm diameter. which is the basis for Eurocode 2. 10A.4. 10A. Munich. Part 1: Design and construction. German Codes .3 Slenderness Effects and Analysis Considerations Slenderness effects are extremely important in designing compression members. In addition. International Design Codes Manual — 399 . The first method is equivalent to the procedure presented in DIN 1045 17. l l For Beams — Prismatic (Rectangular & Square) For Columns — Prismatic (Rectangular.10A. This method has been adopted in the column design in STAAD per the DIN code. In the above input. There are two options by which the slenderness effect can be accommodated. Calculations are based on the user specified properties and the member forces obtained from the analysis.2 Member Dimensions Concrete members which will be designed by the program must have certain section properties input under the MEMBER PROPERTY command. Square. 11 13 PR YD 350. . .5 of DIN 1045. This is due to the fact that load combinations are just algebraic combinations of forces and moments.7. Currently. Although exact curtailment lengths are not mentioned explicitly in the design output (finally which will be more or less guided by the detailer taking into account of other practical considerations).g. use the command PDELTA ANALYSIS instead of PERFORM ANALYSIS in the input file.6. If the section dimensions are inadequate as a singly reinforced section.8.3.10A. . effective depths of the sections are determined with the assumption of single layer of assumed reinforcement and reinforcement requirements are calculated. . note that the proper factored loads (like 1.5 for dead load etc. design of singly reinforced sections only is permitted.Concrete Design Per DIN 1045 The second option is to compute the secondary moments through an analysis. The axial loads and joint displacements are first determined from an elastic stiffness analysis and the secondary moments are then evaluated. The column is designed for the total moment which is the sum of the primary and secondary forces. reinforcing bars are chosen from the internal database in single or multiple layers. Final provisions of flexural reinforcements are made then. Shear reinforcement is calculated to resist both shear forces and torsional moments.1. the user has the choice of printing reinforcements provided by STAAD at 13 equally spaced sections from which the final detailed drawing can be prepared. .25. .9 and 1). . STAAD does not factor the loads automatically. Flexural design of beams is performed in two passes. All of these sections are scanned to determine the design force envelopes. whereas a primary load case is revised during the P-delta analysis based on the deflections. The total number of sections considered is 13 (e. For all these forces.. The secondary moments can be compared to those calculated using the charts of DIN 1045. In the first pass. . The entire flexural design is performed again in a second pass taking into account the changed effective depths of sections calculated on the basis of reinforcement provided after the preliminary design. all active beam loadings are prescanned to identify the critical load cases at different sections of the beams.4 Beam Design Beams are designed for flexure. 10A. 10A.4. Shear and torsional design is performed at the start and end sections of the member at a distance "d" 400 — STAAD.2.4. Each of these sections is designed to resist these critical sagging and hogging moments.4. 10A. Secondary moments are caused by the interaction of the axial loads and the relative end displacements of a member. 0.5. ..) should be provided by the user. The user must note that to take advantage of this analysis. Efforts have been made to meet the guideline for the curtailment of reinforcements as per the DIN code. . shear and torsion. Also. such a message will be printed in the output.2 Design for Shear and Torsion Shear design in STAAD conforms to the specifications of section 17.75.1 Design for Flexure Maximum sagging (creating tensile stress at the bottom face of the beam) and hogging (creating tensile stress at the top face) moments are calculated for all active load cases at each of the above mentioned sections. . To perform this type of analysis. German Codes . all the combinations of loading must be provided as primary load cases and not as load combinations. After the preliminary design.Pro . Column design is done for square. The user has control of the effective length (sk) in each direction by using the ELZ and ELY parameters as described on Table 8A. It is assumed that no bent-up bars are available from the flexural reinforcement to carry and "balance" shear. The maximum shear forces from amongst the active load cases and the associated torsional moments are used in the design. The requirements of DIN 1045-figure 13. and closed hoops for beams subject to torsion.3 Example of Input Data for Beam Design UNIT NEWTON MMS START CONCRETE DESIGN CODE GERMAN FYMAIN 415 ALL FYSEC 415 ALL FC 35 ALL CLEAR 25 MEM 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 TRACK 1. if any. The TRACK parameter may be used to obtain the design details in various levels of detail. The capacity of the concrete in shear and torsion is determined at the location of design and the balance.1. is implemented in the design.away from the node of the member where "d" is the effective depth calculated from flexural design.4. The loading which yields maximum reinforcement is called the critical load.4. All active load cases are tested to calculate reinforcement. Example of Input Data for Column Design UNIT NEWTON MMS START CONCRETE DESIGN CODE GERMAN FYMAIN 415 ALL International Design Codes Manual — 401 . That means the total number of bars will always be a multiple of four (4).5 Column Design Columns are designed for axial forces and biaxial moments at the ends. Stirrups are assumed to be U-shaped for beams with no torsion.4.0 MEMB 2 TO 9 DESIGN BEAM 2 TO 9 END CONCRETE DESIGN 10A. This may cause slightly conservative results in some cases.3 and 17. is carried by reinforcement. for calculating the equilibrium equations for rectangular and circular sections from first principles. 10A. Two-legged stirrups are provided to take care of the balance shear forces acting on these sections. rectangular and circular sections. This means that the slenderness will be evaluated along with e/d to meet the requirements of DIN 1045 section 17. Square and rectangular columns are designed with reinforcement distributed on all four sides equally.4. The following parameters are those applicable to slab design: FYMAIN Yield stress for all reinforcing steel FC Concrete grade CLEAR Distance from the outer surface of the element to the edge of the bar. The reinforcement required to resist the Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist the My moment is denoted as transverse reinforcement. This is considered the same on both top and bottom surfaces of the element. Orthogonal or skew reinforcement may be considered.52 of the Technical Reference Manual. The other parameters shown in Table 10A. The SRA parameter (Set Reinforcement Angle) can be manipulated to introduce resolved BAUMANN forces into the design replacing the pure Mx and My moments. an angle is given in degrees measured from the local element X axis anticlockwise (positive). resolved as an axial force. If SRA is set to -500. German Codes . These moments are obtained from the element force output (see Chapter 2 of the Technical Reference Manual).Concrete Design Per DIN 1045 FC 35 ALL CLEAR 25 MEMB 2 TO 6 MAXMAIN 40 MEMB 2 TO 6 DESIGN COLUMN 2 TO 6 END CONCRETE DESIGN 10A. 402 — STAAD. it must first be modeled using finite elements and analyzed.1 BAUMANN equations If the default value of zero is used.1 are not applicable to slab design.6. The resulting Mx* and My* moments are calculated and shown in the design format. Slabs are designed to specifications as described by BAUMANN of MUNICH which is the basis for Eurocode 2. 10A. These new design moments allow the Mxy moment to be considered when designing the section. The command specifications are in accordance with Section 5.Pro . If however a skew is to be considered. Elements are designed for the moments Mx and My. an orthogonal layout will be assumed.10A. the design will be based on Mx and My forces which are obtained from the STAAD analysis.6 Slab Design To design a slab. SRA Parameter which denotes the angle of direction of the required transverse reinforcement relative to the direction of the longitudinal reinforcement for the calculation of BAUMANN design forces. 7 Design Parameters The program contains a number of parameters which are needed to perform the design. The longitudinal bar is the layer closest to the slab exterior face.The design of the slab considers a fixed bar size of 10 mm in the longitudinal direction and 8 mm in the transverse. Face of support location at end of beam.52. This is the way STAAD works for all codes. 10A.1 of this manual contains a complete list of the available parameters and their default values. its value stays at that specified number until it is specified again. Table 8A. DEPTH YD EFACE 0. Concrete Yield Stress / cube strength ELZ 1. See section 5. It is necessary to declare length and force units as Millimeter and Newton before performing the concrete design.1-German Concrete Design Parameters Parameter Name CODE Default Value Description - Must be specified as DIN1045. CLEAR 25 mm Clear cover for reinforcement measured from concrete surface to closest bar perimeter. Design Code to follow. The default value is provided as YD in MEMBER PROPERTIES.0 25 N/mm 2 FC International Design Codes Manual — 403 . These values may be changed to suit the particular design being performed. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements. ELY 1. measured from the end joint.0 Member length factor about local Y direction for column design. Note: Once a parameter is specified. Table 10A.2 of the Technical Reference Manual. Member length factor about local Z direction for column design. Depth of concrete member.0 Note: Both SFACE & EFACE must be positive numbers. Face of support location at start of beam. A is the angle in degrees.Concrete Design Per DIN 1045 Parameter Name FYMAIN Default Value 420 N/mm 2 Description Yield Stress for main reinforcement (For slabs. Factor by which column design moments are magnified for column design Number of equally-spaced sections to be considered in finding critical moment for beam design. Applicable to shear and torsion reinforcement in beams Maximum required reinforcement bar size. Acceptable bars are per MINMAIN above.Pro . FYSEC 420 N/mm 2 MAXMAIN 50 mm MINMAIN 16 mm MINSEC 8 mm MMAG 1. Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 14 16 20 25 32 40 50 Minimum secondary reinforcement bar size. German Codes . The upper limit is 20.0 SRA 0. (Only applicable for shear .10A. it is 500 N/mm 2 for both directions) Yield Stress for secondary reinforcement a. measured from the start joint.0 404 — STAAD. Applicable to shear and torsion reinforcement in beams.0 NSECTION 10 SFACE 0.use MEMBER OFFSET for bending) 0.0 = Orthogonal reinforcement layout without considering torsional moment Mxy -slabs only -500 = Orthogonal reinforcement layout considering Mxy A = Skew angle considered in BAUMANN equations. 0 Level of detail in output 0. For beam gives min/max steel % and spacing. (see NSECTION) WIDTH ZD Width of concrete member. Critical Moment will not be printed with beam design report. 2. For beams gives area of steel required at intermediate sections. This value default is as provided as ZD in MEMBER PROPERTIES. For columns gives a detailed table of output with additional moments calculated. International Design Codes Manual — 405 .Parameter Name TRACK Default Value Description 0. 1. 406 — STAAD.Pro . Analysis is done for the primary and combination loading conditions provided by the user.Part 1: Design and construction) and Stahlbauten . Facilities are available for member selection as well as code checking. The code checking part of the program also checks the slenderness requirements and the stability criteria. The design philosophy and procedural logistics are based on the principles of elastic analysis and allowable stress design. Parts 1 & 2: Stahlbauten .7 the STAAD Technical Reference Manual. Specify whether to perform code checking or member selection. Specify the design parameter values if different from the default values. The next section describes the syntax of commands used to assign properties from the built-in steel table. International Design Codes Manual — 407 . German Codes . Specify the geometry and loads and perform the analysis. The user is allowed complete flexibility in providing loading specifications and in using appropriate load factors to create necessary loading situations.3 Member Property Specifications For specification of member properties of standard German steel sections. 10B. the steel section library available in STAAD may be used.Pro is capable of performing concrete design based on the German code DIN 18800. 3. 10B. regular stiffness analysis or P-Delta analysis may be specified. The following sections describe the salient features of the design approach.Part 2: Analysis of safety against buckling of linear members and frames) Design of members per DIN 18800 requires the STAAD Eurozone Design Codes SELECT Code Pack. Depending upon the analysis requirements. 2. refer to Section 1. Member properties may also be specified using the User Table facility.Teil 2: Stabilitätsfälle .Knicken von Stäben und Stabwerken (Steel structures . Dynamic analysis may also be performed and the results combined with static analysis results.Teil 1: Bemessung und Konstruktion (Steel structures . Two major failure modes are recognized: failure by overstressing and failure by stability considerations.1 General This section presents some general statements regarding the implementation of the DIN code.10B. It is recommended that you use the following steps in performing the steel design: 1.2 AnalysisMethodology Elastic analysis method is used to obtain the forces and moments for design. For more information on these facilities.Steel Design Per the DIN Code STAAD. 10B. Members are proportioned to resist the design loads without exceedance of the allowable stresses or capacities and the most economical section is selected on the basis of the least weight criteria. A complete listing of the sections available in the built-in steel section library may be obtained using the tools of the graphical user interface. Refer to Section 1.7. 25 TO 35 TA ST HEB300 23 56 TA ST HEA160 10B. The following example illustrates the designation.1 IPE Shapes These shapes are designated in the following way: 20 TO 30 TA ST IPEA120 33 36 TO 46 BY 2 TA ST IPER140 10B. These properties are stored in a database file. 14 15 TA ST I200 (INDICATES AN I-SECTION WITH 200MM DEPTH) 10B.3 I Shapes I shapes are identified by the depth of the section. If called for. Following are the descriptions of different types of sections.2 HE Shapes The designation for HE shapes is similar to that for IPE shapes.4. An example of member property specification in an input file is provided at the end of this section.4.4.4 Built-in German Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. these properties are also used for member design. 10B.4 T Shapes Tee sections are not input by their actual designations. but instead by referring to the I beam shapes from which they are cut. German Codes .10B. For example. Since the shear areas are built into these tables.Steel Design Per the DIN Code 10B. shear deformation is always considered for these members during the analysis.2 of the Technical Reference Manual for additional information.Pro .4. 1 5 TA T HEA220 2 8 TA T IPE120 408 — STAAD. g. 11 TA D U180 27 TA D U280 SP 0.5 LENGTH UNITS) 10B. The above specification may be used when the local z-axis corresponds to the Z-Z axis specified in Chapter 2. respectively.5mm.4. in front of the angle size.5 U Channels The example below provides the command for identifying two channel sections. with or without spacing between them. e. The spacing between the double channels is provided following the expression “SP”.8 Double Angles Short leg back-to-back or long leg back-to-back double angles can be specified by using the word SD or LD. Spacing between the angles is provided by using the word SP and the spacing value following the section name.5 The above section signifies an angle with legs of length 20mm and a leg thickness of 2.5 21 TO 27 TA LD L40X20X4 SP 0. The letter “D” in front of the section name will specify a double channel. type specification "RA" (reverse angle) may be used. If the local y-axis corresponds to the Z-Z axis. The former (U70X40) has a depth of 70mm and a flange width of 40mm. 17 21 TA RA L40X20X5 10B. 11 TA D U70X40 27 TA D U260 10B.4.10B. either SD or LD will serve the purpose.4.6 Double Channels Back-to-back double channels. 14 TO 20 TA SD L40X20X4 SP 0. are available.7 Angles Two types of specifications may be used to describe an angle.5 (INDICATES 2 CHANNELS BACK-TO-BACK SPACED AT 0. The standard angle section is specified as follows: 16 20 TA ST L20X20X2.5 International Design Codes Manual — 409 . In case of an equal angle. D U180. The latter (U260) has a depth of 260mm..4. 15 TO 25 TA ST TUB100603.Steel Design Per the DIN Code 10B.6 is the specification for a tube having sides of 100mm x 60mm and the wall thickness of 3. use PIP followed by numerical value of the diameter and thickness of the section in mm omitting the decimal section of the value provided for diameter. Only code checking and no member selection will be performed for TUBE sections specified this way. 12. Tubes.9MM WALL THICKNESS) 3 64 67 TA ST PIP40612. 10B.Pro .9 Pipes (Circular Hollow Sections) To designate circular hollow sections.9 (60. For example.10 Tubes (Rectangular or Square Hollow Sections) Tube names are input by their dimensions. a width of 6.5 is a tube that has a height of 8.0 WT 6.11 Example SAMPLE INPUT FILE CONTAINING GERMAN SHAPES STAAD SPACE UNIT METER KN JOINT COORDINATES 1 0 0 0 15 140 0 0 MEMBER INCIDENCES 1 1 2 14 410 — STAAD.4MM DIA.4. 6 TA ST TUBE DT 8.10B. of 25 and inside dia. The following example will illustrate the designation.6mm.5MM WALL THICKNESS) Circular hollow sections may also be provided by specifying the outside and inside diameters of the section. For example.0 specifies a pipe with outside dia. Width and Thickness) instead of by their table designations. 10B.3MM DIA. and a wall thickness of 0. 1 TO 9 TA ST PIPE OD 25.5 (406. of 20 in current length units.4.0 TH 0.5 in current length units.0 ID 20. like pipes can also be input by their dimensions (Height. Only code checking and no member selection will be performed if this type of specification is used. 2.4. German Codes . 8 TO 28 TA ST PIP602. 5 * PRINT MEMBER PROPERTIES FINISH 10B. These depend on several factors such as cross sectional properties.5 * PIPES 11 TA ST PIP602.5 Member Capacities The allowable stresses used in the implementation are based on DIN 18800 (Part 1) .0 WT 6.0 * TUBES 13 TA ST TUB100603.LONG LEGS BACK TO BACK 9 TA LD L40X20X4 SP 0.5 * DOUBLE ANGLES . The basic measure of member capacities are the allowable stresses on the member under various conditions of applied loading such as allowable tensile stress. allowable compressive stress etc.6 * TUBES 14 TA ST TUBE DT 8.9 * PIPES 12 TA ST PIPE OD 25. The procedures of DIN 18800 Part 2 are used for stability analysis. unsupported width to International Design Codes Manual — 411 .0 ID 20.SHORT LEGS BACK TO BACK 10 TA SD L40X20X4 SP 0.5 * REVERSE ANGLES 8 TA RA L40X20X5 * DOUBLE ANGLES .0 WT 0. slenderness factors.Section 7.UNIT CM MEMBER PROPERTIES GERMAN * IPE SHAPES 1 TA ST IPEA120 * HE SHAPES 2 TA ST HEB300 * I SHAPES 3 TA ST I200 * T SHAPES 4 TA T HEA220 * U CHANNELS 5 TA ST U70X40 * DOUBLE U CHANNELS 6 TA D U260 * ANGLES 7 TA ST L20X20X2. 2 Checks for Axial Compression The compression capacity for members in compression is determined according to the procedure of DIN 18800. Compressive resistance is a function of the slenderness of the cross-section (Kl/r ratio) and the user may control the slenderness value by modifying parameters such as KY.5 are used. Shear capacities are a function of web depth.5. In addition. The tension capacity of the member is calculated on the basis of the member area.Steel Design Per the DIN Code thickness ratios and so on.5. thickness of flanges.1.3 Checks for Bending and Shear The bending compressive and tensile capacities are dependent on such factors as length of outstanding legs. 412 — STAAD. for members with axial loads and bending. the criteria of DIN 18800(Part 2) .1 Checks for Axial Tension In members with axial tension.4 and 3. Explained here is the procedure adopted in STAAD for calculating such capacities. some or all of these parameter values may have to be changed to exactly model the physical structure. STAAD calculates the tension capacity of a given member based on a user supplied net section factor (NSF -a default value of 1.6 Combined Loading For members experiencing combined loading (axial force. unsupported length of the compression flange (UNL.Section 6. These parameters communicate design decisions from the engineer to the program.Pro . Note: Once a parameter is specified.5. bending.0 for the TRACK parameter to obtain a listing of the bending and shear capacities.0 or 2. see Table 8B. Users may use a value of 1. Members subjected to axial force and bending are checked using the criteria of DIN 18800 (Part 1) . and shear).Sections 3.1) and proceeds with member selection or code checking. 10B. applicable interaction formulas are checked at different locations of the member for all modeled loading situations. German Codes . LY. Depending on the particular design requirements of the situation. This is the way STAAD works for all codes. defaults to member length) etc. 10B. 10B.Part 2. KZ and LZ.7 Design Parameters You are allowed complete control over the design process through the use of parameters described in the following table.10B. 10B. its value stays at that specified number until it is specified again. 10B. the tensile load must not exceed the tension capacity of the member. web thickness etc.0 is present but may be altered by changing the input value. The default parameter values have been selected such that they are frequently used numbers for conventional design.6. Moment factor. Zeta.1-German Steel Design Parameters Parameter Name CODE Default Value Description - Must be specified as DIN18800. pin ended member with central point load. this is the minor axis.0 m KY 1.Table 10B. program will use n = 2.35 4. Check ends plus location of beam 1. Zeta = 1.0 International Design Codes Manual — 413 . Zeta calculated from end moments. fixed ended member.5 for rolled sections and 2. pin ended member with UDL.0 DMAX 1. 3.0 m Maximum allowable depth during member selection Minimum required depth during member selection K value in local y-axis.12 3. DMIN 0. Zeta = 1. defined in Table 10: 1.0 2. CMM 1. 1. Check at every 1/13th of the member length and report the maximum.48. Check at location of maximum MZ along member. Usually. Zeta = 1. CB 0 Beam coefficient n. See section 5. 2. fixed ended member with constant moment. defined in Table 9: If Cb = 0.0 for welded sections.0 check.1 of the Technical Reference Manual. Design Code to follow. BEAM 0. Design only for end sections.0 Number of sections to be checked per member: 0. 414 — STAAD. this is the major axis. Rolled 1. German Codes . 1. Length in local y-axis to calculate slenderness ratio.0 LZ PY NSF RATIO 1. Length in local z-axis to calculate slenderness ratio.Steel Design Per the DIN Code Parameter Name KZ Default Value Description 1. Try only those with a similar name. St 37-2 1.0 Level of detail in output file: 0.0 K value in local z-axis. St E 355 TRACK 0. Output summary of results 1.Pro . Try every section of the same type as the original. LY Member Length Member Length 240 N/sq.mm 1. Net section factor for tension members. St 52-3 2. Built-up SGR 0. Permissible ratio of actual to allowable stresses Control of sections to try during a SELECT process: 0.0 Same as above provided as a factor of actual member length. Strength of steel. Output detailed results UNF 1.0 Grade of steel: 0.10B.0 SAME 0. Output summary of results plus member capacities 2.0 SBLT 0 Specify section as either rolled or builtup: 0. Usually. For example. Refer to Section 2. The code checking output labels the members as PASSed or FAILed.5 of the Technical Reference Manual for general information on Code Checking. Member selection cannot be performed on TUBES. When no sections are specified and the BEAM parameter is set to zero (default). location (distance from start joint) and magnitudes of the governing forces and moments are also printed. the critical condition. Refer to Section 2. governing load case.48. a member specified initially as a channel will have a channel selected for it.9 Member Selection The member selection process basically involves determination of the least weight member that PASSes the code checking procedure based on the forces and moments of the most recent analysis.8 Code Checking The purpose of code checking is to check whether the provided section properties of the members are adequate to carry the forces transmitted to it by the loads on the structure. 10B.9 ALL TRACK 1. Sample Input data for Steel Design UNIT METER PARAMETER CODE GERMAN NSF 0.0 ALL International Design Codes Manual — 415 . Refer to Section 5.85 ALL UNL 10. design will be based on member start and end forces.2 MEMBER 3 4 RATIO 0. The adequacy is checked per the DIN requirements. Code checking is done using forces and moments at specified sections of the members. 10B. and the maximum moment about the major axis is used. Refer to Section 5. Selection of members whose properties are originally provided from a user table will be limited to sections in the user table. In addition. or members listed as PRISMATIC.0 MEMBER 7 KY 1. moments are calculated at every twelfth point along the beam. The section selected will be of the same type as that specified initially.48. If the BEAM parameter for a member is set to 1.Parameter Name UNL Default Value Description Member Length Unrestrained member length in lateral torsional buckling checks.6 of the Technical Reference Manual for general information on Member Selection.2 of the Technical Reference Manual for details the specification of the Code Checking command.3 of the Technical Reference Manual for details the specification of the Member Selection command. PIPES. 10B.Pro . German Codes .Steel Design Per the DIN Code CHECK CODE ALL 416 — STAAD. Section 11 Indian Codes International Design Codes Manual — 417 . 418 — STAAD.Pro . In the above input.1 Section Types for Concrete Design The following types of cross sections for concrete members can be designed. will be assumed to be circular with 350 mm diameter. and L-shapes For Columns — Prismatic (Rectangular. Design of members per IS 456 requires the STAAD India Design Codes SELECT Code Pack. Square. 400 mm overall depth and 100 mm flange depth (See section 6. with only depth and no width provided. flanged or circular and the beam or column design. 11A. 200 width.Pro is capable of performing concrete design based on the Indian code IS 456 2000 Code of Practice for Plain and Reinforced Concrete. ZD 250. Indian Codes . This is the way STAAD works for all codes. International Design Codes Manual — 419 .3 Design Parameters The program contains a number of parameters which are needed to perform design as per IS:456(2000). the first set of members are rectangular (450 mm depth and 250mm width) and the second set of members. The third set numbers in the above example represents a T-shape with 750 mm flange width. ZD 750.20. The following example shows the required input: UNIT MM MEMBER PROPERTY 1 3 TO 7 9 PRISM YD 450. will be done accordingly. 11A.1 of this manual contains a complete list of the available parameters and their default values. 11 13 PR YD 350. Note: Once a parameter is specified. T-Beams. and Circular) 11A.2 Member Dimensions Concrete members which will be designed by the program must have certain section properties input under the MEMBER PROPERTY command. The program will determine whether the section is rectangular.2). ZB 200. These values may be changed to suit the particular design being performed. It is necessary to declare length and force units as Millimeter and Newton before performing the concrete design. 14 TO 16 PRIS YD 400. YB 300.11A. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements. l l For Beams — Prismatic (Rectangular & Square).Concrete Design per IS 456 STAAD. its value stays at that specified number until it is specified again. Table 9A. The column is unbraced about minor axis. Face of support location at end of beam. BRACING 0. 2. 2. The parameter can also be used to check against shear at any point from the end of the member.11A.1-Indian Concrete Design IS456 Parameters Parameter Name CODE Default Value Description - Must be specified as INDIAN. For column members Total depth to be used for design. CLEAR 25 mm 40 mm For beam members.7. Column Design: correspond to the terms "Braced" and "Unbraced" described in Notes 1. 3.2 of the Technical Reference Manual. The column is unbraced about major axis.Concrete Design per IS 456 Table 11A.Pro .0 Note: Both SFACE and EFACE are input as positive numbers. The column is unbraced about both axis. Indian Codes .1 of IS456:2000. and 3 of Clause 39.0 Beam Design: A value of 1. See section 5. 420 — STAAD. This value defaults to YD as provided under MEMBER PROPERTIES. 1. DEPTH YD EFACE 0.0 means the effect of axial force will be taken into account for beam design.52. Design Code to follow. FC FYMAIN 30 N/mm 2 415 N/mm 2 Concrete Yield Stress. Ratio of effective length to actual length of column about minor axis. l ELY 1.0 means ordinary shear check to be performed ( no enhancement of shear strength at sections close to support) For ENSH = a positive value(say x ). shear strength will be enhanced up to a distance y from the end of the member. International Design Codes Manual — 421 .0 ENSH 0. This is used only when a span of a beam is subdivided into two or more parts.5. See Note b below. shear strength will be enhanced at sections (<2d) close to support otherwise ordinary shear check will be performed.(Refer note) l l If default value (0. 40. If this ratio is greater than 2.0) is used the program will calculate Length to Overall Depth ratio.0 ENSH = 1.0 Ratio of effective length to actual length of column about major axis. Perform shear check against enhanced shear strength as per Cl. Yield Stress for main reinforcing steel. shear strength will be enhanced up to a distance x from the start of the member. See Note b below. (Refer note ) For ENSH = a negative value(say –y).Parameter Name ELZ Default Value Description 1. This is used only when a span of a beam is subdivided into two or more parts.5 of IS456:2000. Minimum main reinforcement bar size. A value of 1. (Refer note) 2. Indian Codes . Two faced distribution about major axis. Minimum secondary reinforcement bar size.Pro . Maximum percentage of longitudinal reinforcement in columns. Distance of the start or end point of the member from its nearest support. For column center to center distance between main bars cannot exceed 300 mm. This parameter is used only when a span of a beam is subdivided into two or more parts. The parameter can also be used to check against shear at any point from the start of the member.0 REINF 0.11A.0 Face of support location at start of beam.0 RFACE 4.0 RENSH 0. Tied column. SPSMAIN 25 mm 422 — STAAD. 4. 3.Concrete Design per IS 456 Parameter Name FYSEC Default Value 415 N/mm 2 Description Yield Stress for secondary reinforcing steel. MINMAIN 10 mm MAXMAIN 60 mm MINSEC 8 mm MAXSEC 12 mm RATIO 4.0 will mean spiral reinforcement. Minimum clear distance between main reinforcing bars in beam and column. Maximum secondary reinforcement bar size. Maximum main reinforcement bar size. Two faced distribution about minor axis.0 SFACE 0. It is used to check against shear at the face of the support in beam design. Longitudinal reinforcement in column is arranged equally along 4 faces. ULY 1. column interaction analysis results are printed in addition to TRACK 0. 2. See Note c below. torsion to be considered in beam design. 2. required steel for intermediate sections defined by NSECTION are printed in addition to TRACK 1. torsion to be neglected in beam design.0 WIDTH ZD International Design Codes Manual — 423 . MIDDLE.0 output. Ratio of unsupported length to actual length of column about major axis. Column Design: 0. 9.0 0. critical moments are printed in addition to TRACK 0. This value defaults to ZD as provided under MEMBER PROPERTIES.0 output. output consists of reinforcement details at START.Parameter Name TORSION Default Value Description 0.0 Ratio of unsupported length to actual length of column about minor axis.0 Beam Design: 0. Width to be used for design. a schematic interaction diagram and intermediate interaction values are printed in addition to TRACK 1. 1. ULZ 1. and END. TRACK 0. 1. reinforcement details are printed.0 output. the details of section capacity calculations are printed.0 output. See Note c below. 1. 2 of IS456:2000. For the term "b" in CL 25. The input should be the following: Steps: 424 — STAAD. STAAD uses the ZD dimension of the column. When this condition occurs. l and l . The shear strength will be enhanced up to X meter from both supports. ULY and ULZ parameters are used to calculate unsupported length of column to find minimum eccentricity.2 of IS456:2000.1. you will find two term. In CL 25. each of length L meter.2 of IS456:2000.1 Notes a.0 and 1.1.4 of IS456:2000.2 of IS456:2000. The value of the ENSH parameter (other than 0. Please refer CL 25. STAAD uses the YD dimension of the column.4 of IS456:2000. This term is calculated as l l ULZ multiplied by the member length for the Z axis ULY multiplied by the member length for the Y axis d.0) is used only when the span of a beam is subdivided into two or more parts. The span of the beam is subdivided four parts. Indian Codes .11A.3.1. you will find an expression "unsupported length of column". Please refer CL 25. Refer to Section 9A. b.1.Pro . c. You may specify reinforcing bar combinations through the BAR COMBINATION command. which STAAD calculates ex ey as: l l = ELZ multiplied by the member length (distance between the two nodes of ex the member) l = ELY multiplied by the member length (distance between the two nodes of ey the member) l For the term "D" in CL 25.Concrete Design per IS 456 11A.8 for details. In CL 25. the RENSH parameter is also to be used. ELY and ELZ parameters are used to calculate effective length of column to find whether it is a short or long column. the effect of deflections on moment and forces and the effect of the duration of loads. av becomes zero. ENSH (X-L) MEMB 2 => Shear strength will be enhanced up to a length (X-L) of the member 2. positive sign indicates length measured from start of the member 2. RENSH L MEMB 2 3 => Nearest support lies at a distance L from both the members 2 and 3.0.4 Slenderness Effects and Analysis Consideration Slenderness effects are extremely important in designing compression members. DESIGN BEAM 1 TO 4=> This will enhance the shear strength up to length X from both ends of the beam consisting of members 1 to 4 and gives spacing accordingly. At section = y1 from start of member 1 av = y1 At section = y2 from the start of member 2 av = y2+L At section = y3 from the end of member 3 av = y3+L At section = y4 from end of member 4 av = y4 where tc.1. One option is to perform an exact analysis which will take into account the influence of axial loads and variable moment of inertia on member stiffness and fixed end moments. length measured from the end of the member 5. negative sign indicates length measured from end of the member 4. International Design Codes Manual — 425 . enhanced = 2d tc/av At section 0. STAAD has been written to allow the use of the first option. max. length measured from the start of the member 3. use the command PDELTA ANALYSIS instead of PERFORM ANALYSIS. max. ENSH –L MEMB 4 => Shear strength will be enhanced throughout the length of the member 4. It is felt that this effect may be safely ignored because experts believe that the effects of the duration of loads are negligible in a normal structural configuration. However for any section shear stress cannot exceed tc.order analysis described by IS:456. The P-Delta analysis will accommodate all requirements of the second. To perform this type of analysis. ENSH –(X-L) MEMB 3 => Shear strength will be enhanced up to a length (X-L) of the member 3. The IS:456 code specifies two options by which the slenderness effect can be accommodated (Clause 39. except for the effects of the duration of the loads. Thus enhanced shear strength will become infinity. Hence enhanced shear strength is limited to a maximum value of tc. 11A. 6. ENSH L MEMB 1 => Shear strength will be enhanced throughout the length of the member 1.7). Another option is to approximately magnify design moments. .5. This is due to the fact that load combinations are just algebraic combinations of forces and moments (i..g.25. a P-Delta analysis. . Where ever the rectangular section is inadequate as singly reinforced section.. Note: You must specify the appropriate load factors (e.IS: 456 . In this method. .1. .7. effective depths of the sections are determined with the assumption of single layer of assumed reinforcement and reinforcement requirements are calculated.2000).1. shear and torsion.1 have been implemented in STAAD.1 Design for Flexure Maximum sagging (creating tensile stress at the bottom face of the beam) and hogging (creating tensile stress at the top face) moments are calculated for all active load cases at each of the above mentioned sections. ... Each of these sections is designed to resist both of these critical sagging and hogging moments. it must be realized that the approximate evaluation of slenderness effects is also an approximate method.6.5 for dead load. Flexural design of beams is performed in two passes. presently the flanged section is designed only as singly reinforced section under sagging moment.e. .Pro .Concrete Design per IS 456 Although ignoring load duration effects is somewhat of an approximation. whereas a primary load case is revised during the P-delta analysis based on the deflections. Efforts have been made to meet the guideline for the 426 — STAAD.1.11A. Note: To take advantage of this analysis. all the combinations of loading must be provided as primary load cases and not as load combinations.8.Pro.1 and 39. additional moments are calculated based on empirical formula and assumptions on sidesway (Clause 39. 0. . Final provisions of flexural reinforcements are made then. analysis results).4. Considering all these information. After the preliminary design. reinforcing bars are chosen from the internal database in single or multiple layers. The rules of Clause 39. etc. 11A. In the first pass.75. The total number of sections considered is 13 (e.7. The entire flexure design is performed again in a second pass taking into account of the changed effective depths of sections calculated on the basis of reinforcement provide after the preliminary design.g. . doubly reinforced section is tried. However. all active beam loadings are prescanned to identify the critical load cases at different sections of the beams.3. It may also be noted all flanged sections are automatically designed as rectangular section under hogging moment as the flange of the beam is ineffective under hogging moment. Indian Codes . Loads can be combined prior to analysis using the REPEAT LOAD command.) as STAAD does not factor the loads automatically. .5 Beam Design Beams are designed for flexure.7. as performed by STAAD may be used for the design of concrete members. .2. 1.7. If required the effect the axial force may be taken into consideration. For all these forces. .5.9. All of these sections are scanned to determine the design force envelopes. and 1). They will be checked if the ELY and ELZ parameters are specified. 11A. ) sections along the length of the beam. Shear capacity calculation at different sections without the shear reinforcement is based on the actual tensile reinforcement provided by STAAD program. user has the choice of printing reinforcements provided by STAAD at 11 equally spaced sections from which the final detail drawing can be prepared.00 1 | 50.00 29.0) for the maximum shear forces amongst the active load cases and the associated torsional moments.2. 11A. All beam design outputs are given in IS units.3 Beam Design Output The default design output of the beam contains flexural and shear reinforcement provided at 5 equally spaced (0.00 1 | 533.5.00 1 | 0.00 1 | 1066.0 | 0.00 1 | 0. cmax 11A.3). Shear design are performed at 11 equally spaced sections (0.7 | 0.88 0.0 mm X 400.00 0.5.00 0.curtailment of reinforcements as per IS:456-2000 (Clause 26.00 0.00 0. As per Clause 40. .0 mm SIZE: 300.00 1 | 0.00 1 | International Design Codes Manual — 427 .0 mm 6400.00 0.51 0.41 0. .3 | 0.0 output is presented below: B E A M S M20 (Sec. subjected to a maximum value of τ .0 to 1. Sagging/Hogging moments)| SHEAR (in mm) | P MZ MX Load Case | VY MX Load Case --------------------------------------------------------------------------0.2 Design for Shear Shear reinforcement is calculated to resist both shear forces and torsional moments.00 0. User has option to get a more detail output.61 0.00 0.00 1 | 60.5 of IS:456-2000 shear strength of sections (< 2d where d is the effective depth) close to support has been enhanced. An example of rectangular beam design output with TRACK 2.25.75 and 1. .63 0. 1 D E S I G N R E S U L T DESIGN LOAD SUMMARY (KN MET) --------------------------------------------------------------------------SECTION |FLEXURE (Maxm. Two-legged stirrups are provided to take care of the balance shear forces acting on these sections.00 0.) LENGTH: COVER: 25.0 mm Fe415 (Main) Fe250 N O.00 1 | 40.00 53.5. Although exact curtailment lengths are not mentioned explicitly in the design output (finally which will be more or less guided by the detailer taking into account of other practical consideration). 00 1 | 2133.28 0.00 1 | -30.00 1 | -40.00 1 | 0.00 1 | 30. Indian Codes .00 0.62( 3-25í )| 8í @ 180 mm 2133./Provided reinf.00 1 | 4800.3 | 0.Concrete Design per IS 456 1600.00 1 | 6400.00 1 | 0.00 0.0 | 0.00 1 | -20.00 0.00 0. | (2 legged) --------------------------------------------------------------------------0.0 | 0.62( 3-25í )| 8í @ 180 mm 1600.00 1 | 3733.3 | 0.00 1 | 0.98 0.00 72.00 0.00 1 | 0.28 0.00 0.3 | 0.00 53.00 0.7 | 0.00 1 | 4266.75( 2-25í )| 8í @ 180 mm 533.7 | 0.12( 2-16í )| 632.12( 2-16í )| 237.0 | 0.63 0.00 96.10 0.31 0.Pro .00 1 | -50.62( 3-25í )| 8í @ 180 mm 2666.00 0.00 94.00 1 | 0.62( 3-25í )| 8í @ 180 mm 1066.00 1 | --------------------------------------------------------------------------SUMMARY OF REINF.00/ 402.82/1472.00/ 402.00 86.20 0.00 0.00 0.00 0.31 0.00 1 | 0.00 0.00 0.00 1 | 2666.12( 2-16í )| 0.00 1 | 0.00 72.00 0.61 0.84/1472.00 1 | 5333.10 0.00 0.00/ 402. AREA (Sq.00 0.7 | 0.0 | 0.73 0.00 0.00/ 981.00 1 | 0.20 0.00 1 | 20.11A.73 0.91/1472.00 1 | 3200.7 | 0. | Reqd.00/ 402.0 | 0.00 0.00/ 402.12( 2-16í )| 450.00 1 | 0.3 | 0.00 1 | -10./Provided reinf.00 1 | 10.00 29.00 1 | -60.00 1 | 5866.32/1472.3 | 0.0 | 0.00 0.83/1472.00 1 | 0.88 0.7 | 0.00/ 402.mm) --------------------------------------------------------------------------SECTION | TOP | BOTTOM | STIRRUPS (in mm) | Reqd.51 0.00 0.00 0.20 0.00 1 | 0.00 0.00 94.41 0.00 86.12( 2-16í )| 863.12( 2-16í )| 773.00 0.20 0.62( 3-25í )| 8í @ 180 mm 428 — STAAD. By default.0 mm X 600. rectangular and circular sections. section dimensions and effective length coefficients specified by the user STAAD automatically determine the criterion (short or long) of the column design. 11A.62( 3-25í )| 8í @ 180 mm 4800.0.12( 2-16í )| 450.32/1472. additional moments etc.1).62( 3-25í )| 8í @ 180 mm 6400.3200.75( 2-25í )| 8í @ 180 mm --------------------------------------------------------------------------8í 11A.7 | 0.3 | 0. All major criteria for selecting longitudinal and transverse reinforcement as stipulated by IS:456 have been taken care of in the column design of STAAD.62( 3-25í )| @ 180 mm 3733.12( 2-16í )| 0.7 | 0. Column design is done for square.0 | 0. All active load cases are tested to calculate reinforcement.99/1472.) LENGTH: 3000.12( 2-16í )| 863. Depending upon the member lengths.12( 2-16í )| 237.62( 3-25í )| 8í @ 180 mm 5866.00/ 402.00/ 981.1 Column Design Output Default column design output (TRACK 0.12( 2-16í )| 773.6 Column Design Columns are designed for axial forces and biaxial moments at the ends. 1 D E S I G N Fe415 (Main) R E S U L T S Fe250 (Sec. the output contains intermediate results such as the design forces.12( 2-16í )| 894. The loading which yield maximum reinforcement is called the critical load.0) contains the reinforcement provided by STAAD and the capacity of the section.00/ 402.6.3 | 0.62( 3-25í )| 8í @ 180 mm 5333.0 mm CROSS SECTION: 400.00/ 402.83/1472.00/ 402. square and rectangular columns and designed with reinforcement distributed on each side equally for the sections under biaxial moments and with reinforcement distributed equally in two faces for sections under uniaxial moment.00/ 402.00 International Design Codes Manual — 429 .62( 3-25í )| 8í @ 180 mm 4266.00/ 402. An example of a TRACK 2.0 mm COVER: 40. With the option TRACK 1.0 | 0.0 | 0.91/1472.12( 2-16í )| 632.0 output follows: C O L U M N M20 N O. Default clear spacing between main reinforcing bars is taken to be 25 mm while arrangement of longitudinal bars. User may change the default arrangement of the reinforcement with the help of the parameter RFACE (see Table 8A.82/1472. effective length coefficients. All design output is given in SI units.0 mm ** GUIDING LOAD CASE: 1 END JOINT: 1 SHORT COLUMN DESIGN FORCES (KNS-MET) ----------------------DESIGN AXIAL FORCE (Pu) : 2000.00/ 402.84/1472. 00 MOMENTS DUE TO MINIMUM ECC.31 Muz1 : 269. The typical output for bar combination is shown below: 430 — STAAD. MD2 bar diameter should be greater than MD1 bar diameter). 3619. CONCRETE AREA: 236412.98 (as per Cl. You may use the BAR COMBINATION command to specify two bar diameters to calculate a combination of each bar to be provided at each section. IS456:2000) SECTION CAPACITY BASED ON REINFORCEMENT PROVIDED (KNS-MET) ---------------------------------------------------------WORST LOAD CASE: 1 END JOINT: 1 Puz : 3253.00 SLENDERNESS RATIOS : MOMENTS DUE TO SLENDERNESS EFFECT : MOMENT REDUCTION FACTORS : ADDITION MOMENTS (Maz and May) : TOTAL DESIGN MOMENTS : 160.09 IR: 0. 39.56 Sq.) (Equally distributed) TIE REINFORCEMENT : Provide 8 mm dia.96 ============================================================================ 11A.mm. two at its ends and one at span.7 Bar Combination Initially the program selects only one bar to calculate the number of bars required and area of steel provided at each section along the length of the beam.44 Sq.48 Muy : 170.00 40. The beam length is divided into three parts.42 INTERACTION RATIO: 0.12 dia.59 Muy1 : 168. Ld gives the development length to be provided at the two ends of each section.e. rectangular ties @ 190 mm c/c SECTION CAPACITY BASED ON REINFORCEMENT REQUIRED (KNS-MET) ---------------------------------------------------------Puz : 3244..Pro .11A. (1.11 Sq.00 120. START BAR COMBINATION MD1 <bar diameter> MEMB <member list> MD2 <bar diameter> MEMB <member list> END BAR COMBINATION Note: The bar sizes should be specified in the order of increasing size (i. Indian Codes . STEEL AREA : 3587.mm. REQD.51%.00 120.88 Muz : 271. MAIN REINFORCEMENT : Provide 32 .6.Concrete Design per IS 456 About Z About Y INITIAL MOMENTS : 160.00 REQD.mm. : 52. The syntax for bar combination is given below. Pro.82 | Prov| 804.57 | Ld (mm) | 752. The design is performed for in-plane shear.OUTPUT FOR BAR COMBINATION --------------------------------------------------------------------------| M A I N R E I N F O R C E M E N T | --------------------------------------------------------------------------SECTION | 0.00 | 0.0.2 | 1175.4800. The wall has to be modeled using STAAD’s Surface elements (Refer to Section 5.00 | Prov| 402.0 | 4800.2 | --------------------------------------------------------------------------============================================================================ 11A.8 Wall Design in accordance with IS 4562000 The design of walls in accordance with IS 456-2000 is available in STAAD.0. The use of the Surface element enables the designer to treat the entire wall as one entity. and out-of-plane shear.3 | 752. It greatly simplifies the modeling of the wall and adds clarity to the analysis and design output. in-plane & out-of-plane bending.3 of the Technical Reference Manual).99 | 632.2 | 1175.3 | 752. The results are presented in the context of the entire wall rather than individual finite elements thereby allowing users to quickly locate required information.29 | Ld (mm) | 752.1600. International Design Codes Manual — 431 .2 | --------------------------------------------------------------------------BOTTOM | 4-16í | 2-16í + 2-25í | 416í | | in 1 layer(s) | in 1 layer(s) | in 1 layer(s) | Ast Reqd| 632.00 | 0.82 | 894.0 | 1600.29 | 402.13.06400.43 | 804.0 | | mm | mm | mm | --------------------------------------------------------------------------TOP | 2-16í | 2-16í | 216í | | in 1 layer(s) | in 1 layer(s) | in 1 layer(s) | Ast Reqd| 0.57 | 1384.29 | 402. The shear wall is designed at these horizontal sections. the concentrated (in-plane bending) edge reinforcing and the link required for out-of-plane shear. The output includes the required horizontal and vertical distributed reinforcing.8. 11A. This is the way STAAD works for all codes.54 of the Technical Reference Manual for additional details on shear wall design. If input is 6 (integer number) the program will assume 6 mm diameter bar. Minimum size of vertical reinforcing bars located in edge zones (range 6mm – 36mm). Maximum size of vertical reinforcing bars located in edge zones (range 6mm – 36mm).Concrete Design per IS 456 The program reports shear wall design results for each load case/combination for the specified number of sections given in the SURFACE DIVISION command (default value is 10) command. Note: Once a parameter is specified.11A.2-Shear Wall Design Parameters Parameter Name CLEAR Default Value Description 25 mm Clear concrete cover.Pro . Table 11A. Indian Codes . If input is 6 (integer number) the program will assume 6 mm diameter bar. in current units.1 Design Parameters START SHEARWALL DESIGN CODE INDIAN shearwall-parameters DESIGN SHEARWALL LIST shearwall-list END The following table explains the parameters used in the shear wall design. its value stays at that specified number until it is specified again. EMAX 36 EMIN 8 432 — STAAD. Refer to Section 5. Maximum size of horizontal reinforcing bars (range 6 mm – 36 mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. If input is 6 (integer number) the program will assume 6 mm diameter bar. Minimum size of horizontal reinforcing bars (range 6 mm – 36 mm). If input is 6 (integer number) the program will assume 6 mm diameter bar. Minimum size of links (range 6mm – 16mm). in current units. FC 30 Mpa HMIN 8 HMAX 36 KSLENDER 1. If input is 6 (integer number) the program will assume 6 mm diameter bar. Slenderness factor for finding effective height. Compressive strength of concrete. Maximum size of links (range 6mm – 16mm). in current units.0 LMAX 16 LMIN 6 International Design Codes Manual — 433 .Parameter Name FYMAIN Default Value Description 415 Mpa Yield strength of steel. For instance. 3. 5. each direction 1. Four surfaces are defined by the SURFACE INCIDENCES command. Command SET DIVISION 12 indicates that the surface boundary node-to-node segments will be subdivided into 12 fragments prior to finite element mesh generation.11A. The shear wall design commands are listed between lines START SHEARWALL DES and END. there will be an additional 11 nodes between nodes 2 and 5. Please note that the additional 11 nodes are not individually accessible to the user. The CODE command selects the design code that will be the basis for the design. If input is 6 (integer number) the program will assume 6 mm diameter bar.Pro .Concrete Design per IS 456 Parameter Name TWOLAYERED Default Value Description 0 Reinforcement placement mode: 0. 4. They are created by the program to enable the finite element mesh generation and to allow application of boundary constraints. respectively. For Indian code the parameter is INDIAN. two layers. The SUPPORTS command includes the new support generation routine. If input is 6 (integer number) the program will assume 6 mm diameter bar. As a result. 2. Surface thickness and material constants are specified by the SURFACE PROPERTY and SURFACE CONSTANTS. Minimum size of vertical reinforcing bars (range 6mm – 36mm). VMIN 8 1. As the node-to-node distances were previously subdivided by the SET DIVISION 12 command. each direction VMAX 36 Maximum size of vertical reinforcing bars (range 6mm – 36mm). 434 — STAAD. all 13 nodes will be assigned pinned supports. single layer. Indian Codes . The DESIGN SHEARWALL LIST command is followed by a list of previously defined Surface elements intended as shear walls and/or shear wall components. the line 2 to 5 gen pin assigns pinned supports to all nodes between nodes 2 and 5. Design for in-plane shear (denoted by Fxy in the shear wall force output) By default. Otherwise. design at critical section as per clause no.4. User can change the effective height.2 Technical Overview The program implements provisions of section 32 of IS 456-2000 and relevant provisions as referenced therein.1.4. The design shear strength of concrete is calculated as per clause no. The default effective height is the height of the wall.2 and it is checked with the maximum allowable shear stress as per clause no. 32.3. Design of shear reinforcement is done as per clause no.5. For this purpose. Checking of slenderness limit The slenderness checking is done as per clause no.4. for all active load cases. Design for in-plane bending and vertical load (denoted by Mz & Fy in the shear wall force output) Walls when subjected to combined in-plane horizontal and vertical forces produce in-plane bending in conjunction with vertical load. The following steps are performed for each of the horizontal sections of the wall. 32. Maximum 4% reinforcement is allowed. in-plane bending may be neglected in case a horizontal cross section of the wall is always under compression due combined effect of horizontal and vertical loads.4.2.4.4. The part of the wall which is not having edge reinforcements (i.4.5. 32. The reinforcement is concentrated at both ends (edges) of the wall. 32. is designed again as International Design Codes Manual — 435 . the section is checked for combined vertical load and in-plane moment as column with axial load and uni-axial bending.(a). 32. Design for vertical load and out-of-plane vertical bending (denoted by Fy and My respectively in the shear wall force output) Apart from the in-plane bending and horizontal shear force. the wall is also subjected to outof-plane bending in the vertical and horizontal directions. According to clause no. The limit for slenderness is taken as 30.8. The nominal shear stress is calculated as per clause no. The design for in-plane shear is done as per clause no.1.3. 32. a zone of depth 0. the depth is taken as 0. 32. the program does not design only at the critical section but at all the horizontal sections. The edge reinforcement is assumed to be distributed over a length of 0. 32.2 times horizontal length on each side.8 x horizontal length of wall and breadth is the thickness of the wall..2. Minimum reinforcements are according to clause no.6 x Length of the wall).e.1 can be performed. 32.3. Minimum reinforcements are as per clause no. By suitable use of the surface division command. 32.11A. shear strength of concrete section is calculated considering horizontal reinforcement as tension reinforcement.Concrete Design per IS 456 column under axial load (i.. For shear force in the vertical direction.1. for shear force in the horizontal direction. The wall is assumed as a slab for this purpose.4.1 of SP 16 : 1980 considering vertical reinforcement as tension reinforcement. shear strength of concrete section is calculated as per section 4. 11A. 40.e. vertical load) and out-of-plane vertical bending.5 Design for out-of-plane horizontal bending (denoted by Mx in the shear wall force output) The horizontal reinforcement which is already provided for in-plane shear is checked against out-of-plane horizontal bending. Indian Codes . 40.Pro .8.11A. Similarly.3 Example The following example illustrates the input for the definition of shear wall and design of the wall. Shear reinforcements in the form of links are computed as per the provisions of clause no. The minimum reinforcements and maximum allowable spacings of reinforcements are as per clause no. Maximum allowable shear stresses are as per table 20. … SET DIVISION 12 SURFACE INCIDENCES 2 5 37 34 SUR 1 19 16 65 68 SUR 2 11 15 186 165 SUR 3 10 6 138 159 SUR 4 … SURFACE PROPERTY 1 TO 4 THI 18 SUPPORTS 1 7 14 20 PINNED 2 TO 5 GEN PIN 6 TO 10 GEN PIN 11 TO 15 GEN PIN 19 TO 16 GEN PIN … SURFACE CONSTANTS 436 — STAAD. The nominal shear stresses are calculated as per clause no. Design for out-of-plane shears (denoted by Qx and Qy in the shear wall force output) The out-of-plane shear arises from out-of-plane loading. 32. od1. the wall may be comprise of different wall panels of varying types. and meshing divisions of four edges of the opening(s).17185E+007 POISSON 0. odk Where: n1. Due to the presence of openings.5616 ALPHA 1E-005 … START SHEARWALL DES CODE INDIAN UNIT NEW MMS FC 25 FYMAIN 415 TWO 1 VMIN 12 HMIN 12 EMIN 12 DESIGN SHEA LIST 1 TO 4 END 11A. Design and output are available for user selected locations.. sdj RECOPENING x1 y1 z1 x2 y2 z2 x3 y3 z3 x4 y4 z4 DIVISION od1.17 DENSITY 23. meshing divisions along node-to-node segments..4 Shear Wall Design With Opening The Surface element has been enhanced to allow design of shear walls with rectangular openings. . ni SURFACE s DIVISION sd1. Shear walls modeled in STAAD..Pro may include an unlimited number of openings..8. The automatic meshing algorithm has been improved to allow variable divisions along wall and opening(s) edges. SURFACE INCIDENCE n1. . International Design Codes Manual — 437 . .... s — surface ordinal number.E 2. … . ni — node numbers on the perimeter of the shear wall. … . sdj — number of divisions for each of the node-to-node distance on the surface perimeter. opening(s) corner coordinates. x1 y1 z1 (…) — coordinates of the corners of the opening.. … . Shear wall set-up Definition of a shear wall starts with a specification of the surface element perimeter nodes. sd1. odk — divisions along edges of the opening. 1.. The general format of the command is as follows: PRINT SURFACE FORCE (ALONG ξ) (AT a) (BETWEEN d1. … . d2) LIST s1. d1.si — list of surfaces for output generation ** The range currently is taken in terms of local axis. delineating a fragment of the full cross-section for which the output is desired. For example. Number of sections will be determined from the SURFACE DIVISION X or SURFACE DIVISION Y input values. or as previously input by the SET DIVISION command). If the BETWEEN 438 — STAAD. If command AT is omitted. 2.si Where: ξ — local axis of the surface element (X or Y). Stress/force output printing Values of internal forces may be printed out for any user-defined section of the wall. Note: xd and yd represent default numbers of divisions for each edge of the surface where output is requested. … . sdj or the od1. then the output will be produced for only one section (at the center of the edge). or if any of the numbers listed equals zero. Default locations for stress/force output. the negative range is to be entered. direction Y (default) is assumed. a — distance along the ξ axis from start of the member to the full cross-section of the wall. and design output are set as follows: SURFACE DIVISION X xd SURFACE DIVISION Y yd Where: xd — number of divisions along X axis. output is provided for all sections along the specified (or default) edge.11A. … . d2 — coordinates in the direction orthogonal to ξ . then the corresponding division number is set to the default value (=10. Indian Codes .Pro . design. The output is provided for sections located between division segments. yd — number of divisions along Y axis. If the local axis is directed away from the surface. … . ** s1. if the number of divisions = 2. odk list does not include all node-to-node segments.Concrete Design per IS 456 Note: If the sd1. Note: If command ALONG is omitted. the design proceeds for all cross sections of the wall or panels. Only wall panel design is supported in Indian code. the output is generated based on full cross-section width. a. Shear wall design The program implements different provisions of design of walls as per code BS 8110. Design is performed for the specified horizontal full cross-section. The area of horizontal and vertical bars provided along edges of openings is equal to that of the respective interrupted bars. b.command is omitted. defined by the SURFACE DIVISION X or SURFACE DIVISION Y input values. No panel definition. as applicable. BEAM x1 y1 z1 (…) = coordinates of the corners of the panel. 4. 3. j = ordinal panel number. If opening is found then reinforcement is provided along sides of openings. located at a distance c from the origin of the local coordinates system. COLUMN. Definition of wall panels Input syntax for panel definition is as follows: START PANEL DEFINITION SURFACE i PANEL j ptype x1 y1 z1 x2 y2 z2 x3 y3 z3 x4 y4 z4 END PANEL DEFINITION Where: i = ordinal surface number. General syntax of the design command is as follows: START SHEARWALL DESIGN (…) DESIGN SHEARWALL (AT f2) LIST s ENDSHEARWALL DESIGN Note: If the command AT is omitted. ptype = panel type. International Design Codes Manual — 439 . Panels have been defined. one of: WALL. Pro .440 — STAAD. It accepts all parameters that are needed to perform design as per IS:456. 11B. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements.3 Design Parameters The program contains a number of parameters that are needed to perform design as per IS 13920.Concrete Design per IS 456" on page 419). Therefore ductility is also required as an essential element for safety from sudden collapse during severe shocks. and Circular) 11B. International Design Codes Manual — 441 .Concrete Design per IS 13920 STAAD.1 of this manual contains a complete list of the available parameters and their default values. its value stays at that specified number until it is specified again.Pro is capable of performing concrete design based on the Indian code IS 13920 Code of Practice for Ductile Detailing of Reinforced Concrete Structures Subjected to Seismic Forces. it will be able to sustain the earthquake effects better with some deflection larger than the yield deflection by absorption of energy.11B. These values may be changed to suit the particular design being performed. sudden failure could occur. Note: Once a parameter is specified. 11B. Designs per IS 13920 satisfy all provisions of IS 456 – 2000 and IS 13920 for beams and columns (See "Indian Codes . It is necessary to declare length and force units as Millimeter and Newton before performing the concrete design. Indian Codes . Design of members per IS 1320 requires the STAAD India Design Codes SELECT Code Pack. Over and above it has some other parameters that are required only when designed is performed as per IS:13920. If the structure is brittle.2 Section Types for Concrete Design The following types of cross sections for concrete members can be designed. This is the way STAAD works for all codes. Square. But if the structure is made to behave ductile. l l For Beams: Prismatic (Rectangular & Square) and T-shape For Columns : Prismatic (Rectangular.1 Design Operations Earthquake motion often induces force large enough to cause inelastic deformations in the structure. Table 8A1. For beam members. Column Design: Correspond to the terms "Braced" and "Unbraced" described in Notes 1.Pro . Indian Codes .0 = the column is unbraced about both axis. 3.1 of IS456:2000. and 3 of Clause 39.Concrete Design per IS 13920 Table 11B.0 Beam Design 1. 2.0 = the column is unbraced about major axis. 2. 1.0 = the effect of axial force will be taken into account for beam design.7.0 = the column is unbraced about minor axis.52. BRACING 0.2 of the Technical Reference Manual.11B. This value defaults to YD (depth of section in Y direction) as provided under MEMBER PROPERTIES. For column members CLEAR 25 mm 40 mm 442 — STAAD. DEPTH YD Total depth to be used for design.1-Indian Concrete Design IS 13920 Parameters Parameter Name CODE Default Value Description - Must be specified as IS13920 Design Code to follow. See section 5. The parameter can also be used to check against shear at any point from the end of the member.0 Default value means there will be no member combination.0 International Design Codes Manual — 443 . Ratio of effective length to actual length of column about minor axis.0 Face of support location at end of beam. ELY 1. 1. *** EFACE 0. 2.0 = printout of both sectional force and critical load for combined member in the output.* ELZ 1.0 = no printout of sectional force and critical load for combined member in the output.0 Ratio of effective length to actual length of column about major axis. 3.0 = printout of sectional force for combined member in the output.Parameter Name COMBINE Default Value Description 0. Note: Both SFACE and EFACE are input as positive numbers. 444 — STAAD. (Refer note after Table 8A.5. If this ratio is greater than 2.1) 0.11B.0 = the program will calculate Length to Overall Depth ratio. This is used only when a span of a beam is subdivided into two or more parts. 1. shear strength will be enhanced at sections (<2d) close to support otherwise ordinary shear check will be performed.Pro . 40.1 ) a negative value(say –y) = shear strength will be enhanced up to a distance y from the end of the member.(Refer note after Table 8A.0 = ordinary shear check to be performed ( no enhancement of shear strength at sections close to support) a positive value(say x ) = shear strength will be enhanced up to a distance x from the start of the member.0 Perform shear check against enhanced shear strength as per Cl. Indian Codes .Concrete Design per IS 13920 Parameter Name ENSH Default Value Description 0. This is used only when a span of a beam is subdivided into two or more parts.5 of IS456:2000. This load value must be the unfactored load on span. FYMAIN FYSEC 415 N/mm 2 415 N/mm 2 30 N/mm 2 FC International Design Codes Manual — 445 .Parameter Name EUDL Default Value Description None Equivalent u.(Refer note) Yield Stress for main reinforcing steel.l on span of the beam. Yield Stress for secondary reinforcing steel.2. Concrete Yield Stress. If no u. During design the load value is multiplied by a factor 1. Shear design will be performed based on analysis result.d.d.l is defined factored shear force due to gravity load on span will be taken as zero. No elastic or plastic moment will be calculated. It shall not exceed 300 mm as per Cl. Indian Codes . Time History) and moving load cases are considered.11B. 446 — STAAD. This loadcase can be any static loadcase containing MEMBER LOAD on the beam which includes UNI.Pro . If the HLINK value as provided in the input file does not satisfy the clause the value will be internally assumed as the default one. Internally the unfactored load is multiplied by a factor 1. CMOM member loading is considered only when it is specified in local direction. The load factors are ignored. UMOM member loading is not considered. This parameter is valid for rectangular column. LIN and TRAP member loading. 1893. For combination load only load numbers included in load combination is considered. HLINK Spacing of longitudinal bars measured to the outer face Longer dimension of the rectangular confining hoop measured to its outer face.8.2 during design. 7.l on span of the beam.4. If both EUDL and GLD parameters are mentioned in the input mentioned EUDL will be considered in design Note: No dynamic (Response spectrum. CON. FLOOR LOAD is also considered.d.Concrete Design per IS 13920 Parameter Name GLD Default Value Description None Gravity load number to be considered for calculating equivalent u. CMOM member loading in global direction is not considered. The load can be primary or combination load. in case no EUDL is mentioned in the input. ** International Design Codes Manual — 447 . This implies support exists at start node.Parameter Name IPLM Default Value Description 0. .0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be ignored at end node of beam.0 Default value calculates elastic/plastic hogging and sagging moments of resistance of beam at its ends.0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be ignored at start node of beam. 2. 1. . -2. This implies no support exists at start node.0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be considered at end node of beam. This implies support exists at end node. This implies no support exists at end node. -1.0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be considered at start node of beam. 0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be ignored at both ends of beam.0 Default value calculates elastic/plastic hogging and sagging moments of resistance of beam at its ends.11B. This implies no support exist at either end of the member.0 Maximum percentage of longitudinal reinforcement in columns. 1. 1. Indian Codes .Concrete Design per IS 13920 Parameter Name IMB Default Value Description 0.** MINMAIN 10 mm Minimum main reinforcement bar size. MAXMAIN 60 mm MINSEC 8 mm MAXSEC 12 mm PLASTIC 0. 448 — STAAD. Minimum secondary reinforcement bar size. Maximum main reinforcement bar size.0 = calculation of elastic/plastic hogging and sagging moments of resistance of beam to be considered at both ends of beam.Pro .0 = plastic hogging and sagging moments of resistance of beam to be calculated at its ends. Default value calculates elastic hogging and sagging moments of resistance of beam at its ends. Maximum secondary reinforcement bar size. This implies support exist at both ends of the member. -1.0 RATIO 4. 0 = spiral reinforcement RENSH 0. Refer note after Table 9A. For column center to center distance between main bars cannot exceed 300 mm.0 = torsion to be considered in beam design.* SPSMAIN 25 mm Minimum clear distance between main reinforcing bars in beam and column.0 invokes two faced distribution about minor axis.0 = torsion to be neglected in beam design. TORISION 0.Parameter Name REINF Default Value Description 0.0 Face of support location at start of beam.0 invokes two faced distribution about major axis.0 = Tied column (default) 1.1 RFACE 4.0 = longitudinal reinforcement in column is arranged equally along four faces. This parameter is used only when a span of a beam is subdivided into two or more parts.0 Distance of the start or end point of the member from its nearest support. The parameter can also be used to check against shear at any point from the start of the member. 1.0 0.* Note: Both SFACE and EFACE are input as positive numbers. 0. 3.0 4. SFACE 0.0 International Design Codes Manual — 449 . 2. It is used to check against shear at the face of the support in beam design. * EFACE and SFACE command is not valid for member combination.0 Ratio of unsupported length to actual length of column about minor axis.0 output.0 output. Width to be used for design. ULZ 1. MIDDLE and END. 1.0 output.0 = output consists of reinforcement details at START. 2.0 = a schematic interaction diagram and intermediate interaction values are printed in addition to TRACK 1.0 = required steel for intermediate sections defined by NSECTION are printed in addition to TRACK 1.Concrete Design per IS 13920 Parameter Name TRACK Default Value Description 0.0 = reinforcement details are printed.0 output.Pro . 450 — STAAD. 2. Column Design: 0.0 WIDTH ZD Bar combination has been introduced for detailing. 1. ULY 1. Please refer section 9A1.6 for details. Ratio of unsupported length to actual length of column about major axis. Indian Codes .0 = critical moments are printed in addition to TRACK 0. This value defaults to ZD as provided under MEMBER PROPERTIES.0 = column interaction analysis results are printed in addition to TRACK 0.0 Beam Design: 0.11B. ENSH and RENSH parameters will have to be provided (as and when necessary) even if physical member has been formed. Members to be combined should have same constants (E. and beta angle) 3. 3. These commands are ignored for members forming physical member. alpha. Members to be combined should be continuous. International Design Codes Manual — 451 . columns) cannot be combined. Note: Sectional forces and critical load for combined member output will only be available when all the members combined are successfully designed in both flexure and shear. It will calculate critical loads (similar to that of Design Load Summary) for all active load cases during design. It will calculate sectional forces at 13 sections along the length of the combined member. 7. Members to be combined should have same sectional properties if any single span between two column supports of a continuous beam is subdivided into several members. 5. The maximum number of members that can be combined into one member is 299. At all the intermediate nodes (if any) this calculation will be ignored.e. 4..** IPLM and IMB commands are not valid for member combination. density. Vertical members (i. Members to be combined should lie in one straight line. Poi ratio. It can also be used to combine members to form one continuous beam spanning over more than two supports. The following lines should be satisfied during combination of members: 1. 6. Inclined column support is ignored. 2. If a beam spanning between two supports is subdivided into many sub-beams this parameter will combine them into one member. 4. *** The purpose of COMBINE command is the following: 1. Beams will be combined only when DESIGN BEAM command is issued. Same member cannot be used more than once to form two different combined members. When two or more members are combined during design plastic or elastic moments will be calculated at the column supports. 2. Note: Please note that the program only recognizes column at right angle to the beam. 2 4 1.11B.Concrete Design per IS 13920 11B.Pro .5 4 1.2(DL+LL+SLZ) 2 1.2 4 -1.2(DL+LL+SLX) 1 1.2 4 1.2 LOAD COMB 9 1. Indian Codes .5(DL+LL) 3 1.2 3 1.05 I 1 K 1 B 1 SELFWEIGHT JOINT WEIGHT … LOAD 1 SEISMIC LOAD IN X DIR 1893 LOAD X 1 LOAD 2 SEISMIC LOAD IN Z DIR 1893 LOAD Z 1 LOAD 3 DL MEMBER LOAD …… UNI GY -5 LOAD 4 LL MEMBER LOAD …….2 3 1.2 3 1.2 LOAD COMB 8 1. UNI GY -3 LOAD COMB 5 1.2 LOAD COMB 7 1.5 LOAD COMB 6 1. STAAD SPACE UNIT METER MTON JOINT COORDINATES … MEMBER INCIDENCES … MEMBER PROPERTY INDIAN … CONSTANTS … SUPPORTS … DEFINE 1893 LOAD ZONE 0.1 Example The following lines show a standard example for design to be performed in IS 13920.2(DL+LL-SLZ) 452 — STAAD.3.2(DL+LL-SLX) 1 1. 4.1fck (Clause 6. For all these forces.1.2 PDELTA ANALYSIS LOAD LIST 5 TO 9 START CONCRETE DESIGN CODE IS13920 UNIT MMS NEWTON FYMAIN 415 ALL FC 20 ALL MINMAIN 12 ALL MAXMAIN 25 ALL TRACK 2.2 1. all active beam loadings are prescanned to identify the critical load cases at different sections of the beams. If it exceeds allowable axial stress no design will be performed.3). For design to be performed as per IS:13920 the width of the member shall not be less than 200 mm(Clause 6. 78. All of these sections are scanned to determine the design force envelopes. shear and torsion. Also the member shall preferably have a width-to depth ratio of more than 0. The total number of sections considered is 13.46 NEW/MM EUDL 78. 11B. If required the effect of the axial force may be taken into consideration..2).E.1 Design for Flexure Design procedure is same as that for IS 456.0 ALL *** UNFACTORED GRAVITY LOAD ON MEMBERS 110 TO 112 IS 8 T/M (DL+LL) I.3 (Clause 6.2 4 -1.1) for all active load cases.0 MEMB 110 TO 112 DESIGN BEAM 110 TO 112 DESIGN COLUMN … END CONCRETE DESIGN FINISH 11B.1.46 MEMB 110 TO 112 ** MEMBERS TO BE COMBINED INTO ONE PHYSICAL MEMBER COMBINE 3.0 MEMB 110 TO 112 *** PLASTIC MOMENT CONSIDERED PLASTIC 1.1. The factored axial stress on the member should not exceed 0.4 Beam Design Beams are designed for flexure.2 3 1. However while designing following criteria are satisfied as per IS-13920: International Design Codes Manual — 453 . 11B. Elastic sagging and hogging moments of resistance of the beam section at ends are considered while calculating shear force.1) Shear reinforcement is calculated to resist both shear forces and torsional moments.1b) ρmin = 0.2.3 Beam Design Output The default design output of the beam contains flexural and shear reinforcement provided at 5 equally spaced sections along the length of the beam. 8 times the diameter of the longitudinal bars In no case this spacing is less than 100 mm. Plastic sagging and hogging moments of resistance can also be considered for shear design if PLASTIC parameter is mentioned in the input file. if less than that calculated from IS 456 consideration is provided. The steel provided at each of the top and bottom face.4. Indian Codes . All beam design outputs are given in IS units. at any section.025 4.2. d/4 b. 6. is given by (Clause 6. The minimum grade of concrete shall preferably be M20.4. The minimum tension steel ratio on any face.Concrete Design per IS 13920 1. (Refer Table 8A1.4) 11B.2.Pro .5 of IS13920: The spacing of vertical hoops over a length of 2d at either end of the beam shall not exceed a. The spacing calculated from above.3. (Clause 6.2. at any section. The following criteria are satisfied while performing design for shear as per Cl. 1 D E S I G N R E S U L T 454 — STAAD.3) 3.3) 5.3. (Clause 5. is given by (Clause 6.24Öfck/fy The maximum steel ratio on any face. Procedure is same as that of IS 456. Steel reinforcements of grade Fe415 or less only shall be used. An example of rectangular beam design output with the TRACK 2.0 is presented below: B E A M S N O. The positive steel ratio at a joint face must be at least equal to half the negative steel at that face.11B. (Clause 6.2) 2.3 of IS 13920:1993 revision. at any section. shall at least be equal to one-fourth of the maximum negative moment steel provided at the face of either joint.2) ρmax = 0.2 Design for Shear The shear force to be resisted by vertical hoops is guided by the Clause 6. (Clause 5. User has option to get a more detail output. 00 0.00 1 | 0.00 1 | 1066.00 1 | 6400.00 1 | 3200.00 1 | -10.00 1 | -50.00 1 | 4266.00 1 | 2666.00 0.61 0.00 1 | 0.20 0.00 1 | 40.00 0.63 0.00 1 | 0.00 1 | 60.00 1 | 5333.00 72.00 0.10 0.00 1 | -30.88 0. International Design Codes Manual — 455 .00 1 | 20.00 0.28 0.00 0.00 0.73 0.M20 (Sec.20 0.00 0.0 | 0.00 1 | 5866.00 1 | 3733.00 0.41 0.00 1 | 0.00 0.61 KN.7 | 0.00 1 | 0.00 1 | 30.51 0.00 1 | 0.00 1 | 0.00 0.98 0.3 | 0.00 1 | 50.20 0.88 0.00 0.00 0. Sagging/Hogging moments)| SHEAR (in mm) | P MZ MX Load Case | VY MX Load Case --------------------------------------------------------------------------0.00 72.00 1 | *** DESIGN SHEAR FORCE AT SECTION 0.00 0.0 mm DESIGN LOAD SUMMARY (KN MET) --------------------------------------------------------------------------SECTION |FLEXURE (Maxm.28 0.73 0.00 0.00 0.0 mm Fe415 (Main) SIZE: 300.00 53.00 0.00 29.00 1 | 10.3 | 0.00 1 | 0.00 1 | -60.7 | 0.0 mm 6400.00 0.0 mm X Fe250 400.0 | 0.00 0.00 0.7 | 0.00 1 | -20.0 | 0.00 86.00 0.31 0.00 0.61 0.00 1 | 0.00 1 | 533.00 1 | 0.0 | 0.00 94.0 | 0.00 1 | 0.3 | 0.) LENGTH: COVER: 25.00 1 | 2133.10 0.00 0.00 0.00 0.00 1 | 4800.00 0.00 1 | 0.00 1 | -40.51 0.00 29.00 0.00 1 | 0.31 0.00 1 | 0.00 0.00 86.00 1 | 1600.7 | 0.63 0.3 | 0.00 96.20 0.00 94.00 0.41 0.00 53.00 0.00 0.0 IS 60. 00/ 402.00/ 402.12( 2-16í )| 632.91/1472.12( 2-16í )| 0.84/1472.12( 2-16í )| 863.00/ 402.82/1472.61 KN.00/ 402.82/1472.0 | 0.0 | 0.62( 3-25í )| 8í @ 180 mm 1600.62( 3-25í )| 8í @ 180 mm 4266.0 IS 60.00/ 402.12( 2-16í )| 281.3.3 | 0.00/ 402.3 OF IS-13920 NOTE : MOMENT OF RESISTANCE IS CALCULATED BASED ON THE AREA OF STEEL PROVIDED.75( 2-25í )| 8í @ 100 mm 533.26/1472.7 | 0.12( 2-16í )| 450.62( 3-25í )| 8í @ 180 mm 6400.00/ 402.12( 2-16í )| 450.7 | 0.7 | 0.62( 3-25í )| 8í @ 180 mm 5333.Pro .00/ 402. .62( 3-25í )| 8í @ 180 mm 3733.00/ 402. However following clauses have been satisfied to incorporate provisions of IS 13920: 456 — STAAD.62( 3-25í )| 8í @ 180 mm 1066. All major criteria for selecting longitudinal and transverse reinforcement as stipulated by IS:456 have been taken care of in the column design of STAAD.12( 2-16í )| 281.3.00/ 402.00/ 981.83/1472. Indian Codes .12( 2-16í )| 0.0 | 0.75( 2-25í )| 8í @ 100 mm --------------------------------------------------------------------------- 11B.62( 3-25í )| 8í @ 180 mm 3200.00/ 402. Columns are also designed for shear forces as per Clause 7.62( 3-25í )| 8í @ 180 mm 4800.00/ 402.4.00/ 402.3 | 0.62( 3-25í )| 8í @ 180 mm 5866.00/ 981.5 Column Design Columns are designed for axial forces and biaxial moments per IS 456:2000.62( 3-25í )| 8í @ 180 mm 2666. IF AREA OF STEEL PROVIDED IS MUCH HIGHER COMPARED TO AREA OF STEEL REQUIRED MOMENT OF RESISTANCE WILL INCREASE WHICH MAY INCREASE DESIGN SHEAR FORCE.7 | 0.99/1472.3.26/1472.62( 3-25í )| 8í @ 180 mm 2133.Concrete Design per IS 13920 .83/1472.0 | 0.0 | 0.12( 2-16í )| 773.12( 2-16í )| 773.12( 2-16í )| 632.CLAUSE 6.3 OF IS-13920 *** DESIGN SHEAR FORCE AT SECTION 6400. 7 0.CLAUSE 6.3 | 0.12( 2-16í )| 894.11B.3 | 0.84/1472.12( 2-16í )| 863.91/1472. --------------------------------------------------------------------------STAAD SPACE -PAGE NO. All design output is given in SI units.1.4. 3 D E S I G N R E S U L T S M20 Fe415 (Main) Fe415 (Sec.3) The minimum dimension of column member shall not be less than 200 mm. additional moments etc.2) Steel reinforcements of grade Fe415 or less only shall be used. (Clause 7.4.5. to be used as special confining reinforcement.6) The area of cross-section of hoops provided are checked against the provisions for minimum area of cross-section of the bar forming rectangular. A special output TRACK 9. ============================================================================ C O L U M N N O.2) The ratio of the shortest cross-sectional dimension to the perpendicular dimension shall preferably be not less than 0.3. circular or spiral hoops.1.8) l l l l l l l 11B.0 mm CROSS SECTION: 350. the shortest dimension of column shall not be less than 300 mm. b) 1/6 of clear span of the member. (Clause 5.4. and on either side of any section.l The minimum grade of concrete shall preferably be M20.0) is given below. (Clause 7.7 and 7.0 mm X 400. (Clause 7. and c) 450 mm. except where special confining reinforcement is provided.3) Special confining reinforcement shall be provided over a length l from each joint face.3) The spacing of hoops shall not exceed half the least lateral dimension of the column. (Clause 7.0 mm ** GUIDING LOAD CASE: 5 END JOINT: 2 SHORT COLUMN DESIGN FORCES (KNS-MET) ----------------------DESIGN AXIAL FORCE (Pu) : 226. An example of a column design output (with option TRACK 1. the output contains intermediate results such as the design forces. (Clause 7. (Clause 7.1) The spacing of hoops used as special confining reinforcement shall not exceed ¼ of minimum member dimension but need not be less than 75 mm nor more than 100 mm.0 is introduced to obtain the details of section capacity calculations.) LENGTH: 3000. (Clause 5.1 Column Design Output Default column design output (TRACK 0.7 International Design Codes Manual — 457 . For columns having unsupported length exceeding 4m.0) contains the reinforcement provided by STAAD and the capacity of the section. With the option TRACK 1. where flexural yielding may occur.4.4. o towards mid span. effective length coefficients.0.0 mm COVER: 40. The length l shall not be less than a) larger lateral dimension of the member at the o section where yielding occurs. 08 REQD. IS456:2000) ============================================================================ ********************END OF COLUMN DESIGN RESULTS******************** 11B.28 MOMENTS DUE TO MINIMUM ECC.0 mm from each joint face towards midspan as per Cl.6 of IS-13920. TIE REINFORCEMENT : Provide 10 mm dia.Concrete Design per IS 13920 About Z About Y INITIAL MOMENTS : 0.52 Muz1 : 178. rectangular ties @ 85 mm c/c over a length 500.69%. 3769.53 146.4.20 dia. : 4. STEEL AREA : 3313.71 Muy1 : 150.53 4.64 146.) (Equally distributed) CONFINING REINFORCEMENT : Provide 10 mm dia. Indian Codes . MAIN REINFORCEMENT : Provide 12 . 7.mm.53 SLENDERNESS RATIOS : - MOMENTS DUE TO SLENDERNESS EFFECT : - MOMENT REDUCTION FACTORS : - ADDITION MOMENTS (Maz and May) : - TOTAL DESIGN MOMENTS : 4.00 (as per Cl.56 Sq.31 76.mm. (2.28 ** GUIDING LOAD CASE: 5 Along Z Along Y DESIGN SHEAR FORCES : 43.6 Bar Combination Initially the program selects only one bar to calculate the number of bars required and area of steel provided at each section along the length of the beam.91 Sq. You may use the 458 — STAAD.6.Pro .75 INTERACTION RATIO: 1. rectangular ties @ 175 mm c/c SECTION CAPACITY (KNS-MET) -------------------------Puz : 2261.11B. 39. 0 | 4800.00 | 0.29 | Ld (mm) | 752.1600.0.00 | Prov| 402.4800.BAR COMBINATION command to specify two bar diameters to calculate a combination of each bar to be provided at each section.0.0 | 1600. The syntax for bar combination is given below. two at its ends and one at span..99 | 632.2 | --------------------------------------------------------------------------BOTTOM | 4-16í | 2-16í + 2-25í | 416í | | in 1 layer(s) | in 1 layer(s) | in 1 layer(s) | Ast Reqd| 632.06400.57 | International Design Codes Manual — 459 .3 | 752.57 | 1384. The beam length is divided into three parts.00 | 0.43 | 804.0 | | mm | mm | mm | --------------------------------------------------------------------------TOP | 2-16í | 2-16í | 216í | | in 1 layer(s) | in 1 layer(s) | in 1 layer(s) | Ast Reqd| 0.82 | 894. Ld gives the development length to be provided at the two ends of each section. START BAR COMBINATION MD1 <bar diameter> MEMB <member list> MD2 <bar diameter> MEMB <member list> ENDBAR COMBINATION Note: The bar sizes should be specified in the order of increasing size (i.29 | 402.e.2 | 1175. MD2 bar diameter should be greater than MD1 bar diameter). The typical output for bar combination is shown below: OUTPUT FOR BAR COMBINATION --------------------------------------------------------------------------| M A I N R E I N F O R C E M E N T | --------------------------------------------------------------------------SECTION | 0.82 | Prov| 804.29 | 402. 2 | --------------------------------------------------------------------------============================================================================ 11B.29 mm 2 = 226. Indian Codes .5 N/mm 2 Length. L = 4. fck = 20 N/mm 2 Clear cover = 25 mm Bar diameter = 12 mm Effective depth.1 .Pro . b = 250 mm and depth. w = 6.1 For Beam No.Concrete Design per IS 13920 Ld (mm) | 752.7 Verification Example Sample example showing calculation of design shear force as per Clause 6.29 mm 2 460 — STAAD. fy = 415 N/mm 2 Characteristic strength of concrete.3.11B.3 Figure 11B.19 mm 2 = 226. d = 469 mm Eudl.2 * w * L / 2 = 15600N st_Top_A st_Bot_A st_Top_B st_Bot_B = 339.Example problem 11B. 1 and 2 Section width.19 mm 2 = 339.000 mm A A A A Steps Calculation of Simple Shear Simple shear from gravity load on span = Va = Vb = 1. D = 500 mm Characteristic strength of steel.2 | 1175.7.3 | 752. as = Hogging Moment Of Resistance of End A Micah = Sagging Moment Of Resistance of End A Mu.05 N = 54003057.45 N = 54003057. Figure 11B.45 N = 36768130.a = Vur.14022 N .Sway to right FIG1: SWAY TO RIGHT Vur.ah + Mu.bh ) / L ] = Figure 11B.87 * fy * Ast_Top_A * d * ( 1 .87 * fy * Ast_Bot_B * d * ( 1 .1.87 * fy * Ast_Bot_A * d * ( 1 .14022 N International Design Codes Manual — 461 .4 [ ( Mu.Calculation of Moment Of Resistances Based On Area Of Steel Provided Sagging Moment Of Resistance of End A Mu.as + Mu.4 [ ( Mu.Sway to left -10137.1.bs ) / L ] = 53402.4 [ ( Mu.a = Vul.22202.bs ) / L ] = Va .3 .Ast_Bot_B * fy / b * d * fck) 0.87 * fy * Ast_Top_B * d * ( 1 .4 [ ( Mu.Ast_Bot_A * fy / b * d * fck) 0.as + Mu.69104 N Vul.05 N Resistance of End A Mob = / b * d * fck) Calculation of shear force due to the formation of a plastic hinge at both ends of the beam plus the factored gravity load on the span.bh ) / L ] = Va + 1.b = Va .69104 N 41337.Ast_Top_B* fy = 36768130.2 . bs = Hogging Moment Of 0.b = Va + 1.ah + Mu.Ast_Top_A * fy / b * d * fck) 0. mm 226. Vur. Vul.2 * w * L / 2 load on span = Calculation of Moment Of Resistances Based On Area Of Steel Provided Sagging Moment Of Resistance of End A Mu. Va.Ast_Bot_B * fy / b * d * fck) 0.Ast_Top_B* fy / b * = 63326721.Concrete Design per IS 13920 Design Shear Force Shear Force From Analysis At End A .87 * fy * Ast_Bot_A * d * ( 1 . Indian Codes .5 N = 48452983 N = 11700N Width b Depth D 300 mm 450 mm 415 N/sq.anl. Vu.b. mm 25 mm 12 mm 419 mm 6.56 N 53402.Ast_Top_A * fy / b * d * fck) 0.5 N = 32940364.bh = 0. mm 3000 mm 226.anl.14022 N -6.bs = Hogging Moment Of Resistance of End A Mu.anl = Design Shear Force At End A.anl = Design Shear Force At End B.ah = Sagging Moment Of Resistance of End A Mu.87 * fy * Ast_Bot_B * d * ( 1 .2 For Beam No. mm 20 N/sq. mm 452.44 N 41337.5 N/sq.a) = Shear Force From Analysis At End B .19 sq. Vb. mm 462 — STAAD.29 sq.3 N d * fck) = 32940364.a. mm 339.69104 N 11B.7.11B.b = Max ( Vb. Vul. Vu.Pro . 3 Section Characteristic Strength of Steel fy Characteristic Strength of Concrete fck Clear Cover Bar Diameter Effective Depth d Eudl w Length L Ast_Top_A Ast_Bot_A Ast_Top_B Ast_Bot_B Calculation of Simple Shear Simple shear from gravity Va = Vb = 1.as = Hogging Moment Of Resistance of End A Mu.87 * fy * Ast_Top_A * d * ( 1 . Vur.a = Max ( Va.Ast_Bot_A * fy / b * d * fck) 0.b) = 11.87 * fy * Ast_Top_B * d * ( 1 .39 sq.19 sq. anl.a.a = Vul.Calculation of shear force due to the formation of a plastic hinge at both ends of the beam plus the factored gravity load on the span.bs ) / L ] = 42444.b.bh ) / L ] = Va + 1.34 N Design Shear Force Shear Force From Analysis At End A .anl = Design Shear Force At End A. Vb.anl.b = Max ( Vb.bh ) / L ] = Sway to left -40463.4 [ ( Mu.862 N 63863.81 N 63863.a = Vur. Vul.bs ) / L ] = Va . Va.4 [ ( Mu.ah + Mu. Figure 11B.b) = -23. Vur.4 .Sway to right Vur. Vu.1. Vu.ah + Mu.31 N 42444.3402 N International Design Codes Manual — 463 .anl = Design Shear Force At End B.as + Mu.862 N Vul.862 N -10.as + Mu.a = Max ( Va.4 [ ( Mu.3402 N -15144. Vur.1.b = Va + 1.a) = Shear Force From Analysis At End B . Vul.b = Va .4 [ ( Mu. Pro .464 — STAAD. International Design Codes Manual — 465 .1984 General construction in steel . if different from the default values. Specify whether to perform member selection by optimization. Note: Steel design per the limit state method in IS 800 is also available in the Steel Design mode in the Graphical User Interface. Members are proportioned to resist the design loads without exceeding the allowable stresses and the most economic section is selected on the basis of least weight criteria. The member design facilities provide the user with the ability to carry out a number of different design operations. Specify design parameter values. Design of members per IS 800 requires the STAAD Indian Design Codes SELECT Code Pack.1 Design Operations STAAD contains a broad set of facilities for designing structural members as individual components of an analyzed structure. The code checking part of the program checks stability and strength requirements and reports the critical loading condition and the governing code criteria.Code of practice. 11C. Indian Codes . The operations to perform a design are: l Specify the members and the load cases to be considered in the design. and failure by stability considerations. Two major failure modes are recognized: failure by overstressing. These facilities may be used selectively in accordance with the requirements of the design problem.13 describes the specification of steel sections. 11C. The flowing sections describe the salient features of the allowable stresses being calculated and the stability criteria being used. The entire ISI steel section table is supported.Pro is capable of performing steel design based on the Indian code IS 800 . Specify whether to perform code checking or member selection.11C.2 General Comments This section presents some general statements regarding the implementation of Indian Standard code of practice (IS:800-1984) for structural steel design in STAAD. The design philosophy and procedural logistics for member selection and code checking are based upon the principles of allowable stress design.Steel Design per IS 800 1984 STAAD. Section 11C. l l l These operations may be repeated by the user any number of times depending upon the design requirements. It is generally assumed that the user will take care of the detailing requirements like provision of stiffeners and check the local effects such as flange buckling and web crippling. 1 Axial Stress Tensile Stress The allowable tensile stress. It is a method for proportioning structural members using design loads and forces. σ in MPa on the net effective area of the sections at shall not exceed σat = 0.11C.6·f nor the permissible stress s calculated based on the following equation (per y ac Clause: 5.3 Allowable Stresses The member design and code checking in STAAD are based upon the allowable stress design method as per IS:800 (1984).1984 11C.Pro . The permissible stress in axial tension. allowable stresses. ratio of the effective length to appropriate radius of gyration n = A factor assumed as 1. will discuss the salient features of the allowable stresses specified by IS:800 and implemented in STAAD. and design limitations for the appropriate material under service conditions.6·fy Where: f = minimum yield stress of steel in Mpa y Compressive Stress Allowable compressive stress on the gross section of axially loaded compression members shall not exceed 0. It would not be possible to describe every aspect of IS:800 in this manual.2 Bending Stress The allowable bending stress in a member subjected to bending is calculated based on the following formula: (Clause: 6. in Mpa y f cc = Elastic critical stress in compression = π 2 E/λ2 E = Modulus of elasticity of steel.1.3. however. 11C. 11C. Indian Codes .1) 466 — STAAD.1): σac = 0.6{( fcc · fy )/[( fcc)n + (fy )n ]1/n } Where: σ ac = Permissible stress in axial compression. in Mpa f = Yield stress of steel.4. Appropriate sections of IS:800 will be referenced during the discussion of various types of allowable stresses.Steel Design per IS 800 . as calculated in STAAD as per IS:800 is described below.2. 2 X 105 Mpa λ=l/r = Slenderness ratio of the member. This section.3. 5(10) 5 1 π 20 ry D 2 in MPa (1 / ry) 2 k = a coefficient to allow for reduction in thickness or breadth of flanges 1 between points of effective lateral restraint and depends on y.2) σ bc = 0.66 fcbf y (f ) + f n y cb n () 1/n Clause 6. and depends on w. 2 the ratio of the moment of inertia of the compression flange alone to that of the sum of the moment of the flanges each calculated about its own axis parallel to the y-yaxis of the girder.4.2. 1 = effective length of compression flange International Design Codes Manual — 467 .3 Where: f y = Yield stress of steel.66 fy Where: σ σ f bt bc = Bending stress in tension = Bending stress in compression = Yield stress of steel. in Mpa n = A factor assumed as 1. at the point of maximum bending moment. f cb = Elastic critical stress in bending. The maximum permissible bending compressive stress shall be obtained by the following formula: (Clause: 6.2. calculated by the following formula: c2 fcb = k 1 X + k 2Y c 1 Where: X = Y 1+ Y= 26.σbt or σbc = 0. the ratio of the total area of both flanges at the point of least bending moment to the corresponding area at the point of greatest bending moment between such points of restraint. in MPa y For an I-beam or channel with equal flanges bent about the axis of maximum strength (z-z axis). the maximum bending compressive stress on the extreme fibre calculated on the effective section shall not exceed the values of maximum permissible bending compressive stress. k = a coefficient to allow for the inequality of flanges. Users should note that when the TRACK parameter is set to 1. Indian Codes . Note: Once a parameter is specified.1. In the absence of any user provided information. sidesway will be assumed.(a) for intermediate points. the gross section is taken as 2/3 times the total flange area.1984 r = radius of gyration of the section about its axis of minimum y strength (y-y axis) T = mean thickness of the compression flange.0.3 Shear Stress Allowable shear stress calculations are based on Section 6.3. its value stays at that specified number until it is specified again. detailed design output will be provided. and allowable shear stress (FV) will be printed out in Member Selection and Code Check output in Mpa.(b) for support points.4 Design Parameters In STAAD implementation of IS:800.Steel Design per IS 800 .3. 11C.1 of this section along with their default values and applicable restrictions.1.4 Combined Stress Members subjected to both axial and bending stresses are proportioned accordingly to section 7 of IS:800.1. Available design parameters to be used in conjunction with IS:800 are listed in Table 7B. tension (FTY & FTZ). 11C. 468 — STAAD. This is the way STAAD works for all codes.c = respectively the lesser and greater distances from the section neutral 1 2 axis to the extreme fibres.0 and use in conjunction with this code. and equation of Section 7. is equal to the area of horizontal portion of flange divided by width. D = overall depth of beam c .3.1. the gross section taken into consideration consist of the product of the total depth and the web thickness. is required to be satisfied. 11C. Cm coefficients are calculated according to the specifications of Section 7.1.1.2. the user is allowed complete control of the design process through the use of design parameters. allowable bending stresses in compression (FCY & FCZ). information regarding occurrence of sidesway can be provided through the use of parameters SSY and SSZ. For shear parallel to the flanges.11C. When TRACK is set to 2.Pro . For shear on the web. All members subject to bending and axial compression are required to satisfy the equation of Section 7.4 of IS:800. For combined axial tension and bending the equation of Section 7. 1.0 = calculate section forces at twelfth points along the beam.48. DJ1 DJ2 End Joint of member DMAX DMIN FYLD 100.0 cm.1 of the Technical Reference Manual. 250 MPA (36. CMY CMZ 0. denoting starting point for calculation of "Deflection Length" (See Note 1) Joint No.0 = design only for end moments and those at locations specified by the SECTION command. BEAM 3. design at each intermediate location and report the critical location where ratio is maximum. 0.1-Indian Steel Design IS 800:1984 Parameters Parameter Name CODE Default Value Description Must be specified as INDIAN Design Code to follow. Minimum allowable depth. Yield strength of steel. See section 5.0 cm. denoting end point for calculation of "Deflection Length" (See Note 1) Maximum allowable depth.0 0. allowable local deflection Joint No.Table 11C.85 for sidesway and calculated for no sidesway None (Mandatory for deflection check) Start Joint of member Cm value in local y & z axes DFF "Deflection Length" / Maxm.25 KSI) International Design Codes Manual — 469 . Pro .0 SSZ 0.0 = No sidesway KZ 1.11C.0 = Sidesway in local yaxis. Net section factor for tension members. Indian Codes .0 Same as above except in local z-axis. Same as above except in local z-axis (major). 1. this is major axis. K value in local z-axis.0 PROFILE - RATIO 1. Used to search for the lightest section for the profile(s) specified for member selection.Steel Design per IS 800 . Usually.0 Default Value Description K value in local y-axis.48. Memb.) NSF 1. Allowable Kl/r for slenderness calculations for tension members.1 of the Technical Reference Manual for details. Allowable Kl/r for slenderness calculations for compression members. TMAIN 400 (Tension Memb) 470 — STAAD. this is minor axis. 0.0 SSY 0. Length in local y-axis to calculate slenderness ratio.1984 Parameter Name KY 1. Usually. See Section 5.0 LY Member Length LZ Member Length MAIN 180 (Comp. Permissible ratio of the actual to allowable stresses. in some situations.1) UNF 1. Thus.1 Notes a. It may be noted that for most cases the "Deflection Length" will be equal to the length of the member. UNL Member Length 11C.0 Same as above provided as a fraction of actual member length.4. refer to the figure below where a beam has been modeled using four joints and three members.0 = Print expanded output. The “Deflection Length” for all three members will be equal to the total length of the beam in this case. and 3. If there is deflection check it will also print the governing load case number for deflection check whenever critical condition for design is not DEFLECTION. 2. DJ1 should be 1 and DJ2 should be 4.8B. D = Maximum local deflection for members 1. "Deflection Length" is defined as the length that is used for calculation of local deflections within a member.0 = Print all critical member stresses 2.Parameter Name TRACK Default Value 0. The parameters DJ1 and DJ2 should be used to model this situation.0 Description 0. Unsupported length for calculating allowable bending stress. For example. A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. PARAMETERS International Design Codes Manual — 471 . the "Deflection Length" may be different.0 = Suppress critical member stresses 1. (see fig. for all three members here. However. etc.11C. The deflection check may be controlled using three parameters which are described in Table 11C.Pro . In STAAD implementation of IS:800.1.).6 Truss Members As mentioned earlier.7 Deflection Check This facility allows the user to consider deflection as a criteria in the CODE CHECK and MEMBER SELECTION processes. 11C. If DJ1 and DJ2 are not used. it is wise to declare it as a truss member rather than as a regular frame member with both ends pinned. Therefore.8 Code Checking The purpose of code checking is to verify whether the specified section is capable of satisfying applicable design code requirements. The above parameters may be used in conjunction with other available parameters for steel design. appropriate maximum slenderness ratio can be provided for each member. compression members will be checked against a maximum value of 180 and tension members will be checked against a maximum value of 400. 11C. The code checking is based on the IS:800 (1984) requirements. So in design no time is wasted in calculating bending or shear stresses. a truss member is capable of carrying only axial forces.Steel Design per IS 800 . The local deflection calculation is based on the latest analysis results. thus reducing design time considerably.7 of IS:800 summarizes the maximum slenderness ratios for different types of members. Indian Codes . Section 3.5 Stability Requirements Slenderness ratios are calculated for all members and checked against the appropriate maximum values. ALL DJ1 1 ALL DJ2 4 ALL b. Forces and moments at specified sections of the members are utilized for the code checking calculations. "Deflection Length" will default to the member length and local deflections will be measured from original member line. if there is any truss member in an analysis (like bracing or strut. If no maximum slenderness ratio is provided. 11C. Sections may be specified using the BEAM parameter or the 472 — STAAD. 11C. c. Note that deflection is used in addition to other strength and stability related criteria.1984 DFF 300. the critical condition (applicable IS:800 clause no. The user may start without a specifically designated section. An optimum member size is determined through successive analysis/design iterations. Refer to Section 2. the search for the lightest section is restricted to that profile. However. The process of MEMBER SELECTION may be controlled using the parameters listed in Table 11C.9 Member Selection STAAD is capable of performing design operations on specified members.) must be specified using the ASSIGN command (see Chapter 6).) as originally specified by the user. Once an analysis has been performed. Member selection may be performed with all types of steel sections listed in Section 11C. 11C.48. Refer to Section 5. 11C. Member selection can not be performed on members whose cross sectional properties are specified as PRISMATIC. Selection of members. Refer to Section 5.10 Member Selection By Optimization Steel section selection of the entire structure may be optimized. Refer to Section 5.11 Tabulated Results of Steel Design For code checking or member selection.4 of the Technical Reference Manual for additional details. the code checking is based on forces and moments at the member ends. the program can select the most economical section. Channel etc. The optimization is based on member stiffness contributions and corresponding force distributions. whose properties are originally provided from user specified table.6 of the Technical Reference Manual for general information on Member Selection. The optimization method utilizes a state-of-the -art numerical technique which requires automatic multiple analysis. In addition.48.2 of the Technical Reference Manual for details the specification of the Code Checking command. Up to three (3) profiles may be provided for any member with a section being selected from each one. the lightest section. It may be noted that the parameters DMAX and DMIN may be used to specify member depth constraints for selection. 11C. The section selected will be of the same type (I-Section. COLUMN. the program produces the result in a tabulated fashion.SECTION command.5 of the Technical Reference Manual for general information on Code Checking. governing load case. The code checking output labels the members as PASSed or FAILed. will be limited to sections in the user provided table. The items in the output table are explained as follows: International Design Codes Manual — 473 . This method requires substantial computer time and hence should be used with caution. the section profile type (BEAM. If no sections are specified. location (distance from the start) and magnitudes of the governing forces and moments are also printed out.12 and user provided tables.48. that is. ANGLE etc. If PROFILE parameter is provided.). which satisfies the applicable code requirements.1. Refer to Section 2. CHANNEL.3 of the Technical Reference Manual for details the specification of the Member Selection command. | |MEMBER 7 * | INDIAN SECTIONS | | AX = 85.4 | 474 — STAAD. RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition. FX. MY.Steel Design per IS 800 . LOCATION specifies the actual distance from the start of the member to the section where design forces govern. only FX.Pro .( 800) v1. Normally a value of 1.1984 MEMBER the member number for which the design is performed TABLE the INDIAN steel section name which has been checked against the steel code or has been selected. Indian Codes . Note: If the parameter TRACK is set to 1.11C.0.0 IS- ******************************************** |-------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN CM UNIT | | * |=============================| ===|=== ----------. allowable axial stress in compression (FA). CRITICAL COND the section of the IS:800 code which governs the design. and allowable shear stress (FV).0 | | * | ST ISWB400 | | --Z AY = 34. in most cases. moment in local y-axis and moment in local z-axis respectively.MY and MZ are printed since they are the ones which are of interest. and MZ provide the axial force.0 or less will mean the member has passed. RESULT prints whether the member has PASSED or FAILed. the program will block out part of the table and will print allowable bending stresses in compression (FCY & FCZ) and tension (FTY & FTZ). LOADING provides the load case number which governs the design. When the parameter TRACK is set to 2.0 for all members parameter code values are as shown in the following example. Although STAAD does consider all the member forces and moments (except torsion) to perform design.PRO CODE CHECKING . If the RESULT is FAIL. STAAD. there will be an asterisk (*) mark in front of the member number. 0 | | DFF = 0.7 | | IS-800 * =============================== ===|=== = 138.1( KN-METR) | |PARAMETER |L1 STRESSES | |IN NEWT MM | NEWT MM| |--------------.|DESIGN CODE * | | | 34.40 + = 165.3 | | * |<---LENGTH (ME= 3.9 | L3 = 95.9 +---+---+---+---+---+---+---+---+---+---| = 0.0 | = 139.1 + = 1.0 ABSOLUTE MZ ENVELOPE = 17.0 | | CMZ = 0.0 | | UNL = 3000.) | | | | MAX FORCE/ MOMENT SUMMARY ( KN-METR) | | ------------------------| | | | AXIAL SHEAR-Y SHEAR-Z MOMENT-Y MOMENT-Z | | | = AZ SY SZ RY RZ IN --FA fa FCZ FTZ FCY FTY fbz fby FV fv International Design Codes Manual — 475 .2 | = 150.8 | | * = 1171.0 + = 165.1 | | (WITH LOAD NO.0 90.5 = 100.0 | |************* = 16.60 | = 165.+ ----------| | KL/R-Y= 74.6 | | | | 112.0 | | KL/R-Z= 18.0 | | FYLD = 249.00 --->| = 4.7 | | NSF = 0.0 | | dff = 0.0 | | CMY = 0.9 | | C = 400. Following are the descriptions of all the types of sections available: 11C. ISLB.0 0.1 Rolled Steel Beams (ISJB.g.12.2 BEND C 0.0 -112. These properties are stored in memory corresponding to the section designation (e. If called for. Almost all ISI steel tables are available for input. ISMB and ISHB) All rolled steel beam sections are available the way they are designated in the ISI handbook (e.684 1 | | 7..g.0 | | LOADING 1 | | | -23.) 476 — STAAD.0 0 |**************************************************************************| |* *| |* DESIGN SUMMARY ( KN-METR) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS 7. Since the shear areas are built in to these tables. etc.0 0 0.1 | | LOCATION 0.).1 0. etc.39 T 0.6 3.0 1 0.Steel Design per IS 800 . ISMB250.11C. the properties are also used for member design. ISWB400. ISJB225.Pro . A complete listing of the sections available in the built-in steel section library may be obtained using the tools of the graphical user interface.12 Indian Steel Table This is an important feature of the program since the program will read section properties of a steel member directly from the latest ISI steel tables (as published in ISI-800).00 | |* *| |**************************************************************************| 11C. Indian Codes .0 0.1984 | VALUE 112.1.9 0. shear deformation is always considered for these members.0 3 60.. The standard angle is specified as: 51 52 53 TA ST ISA60X60X6 International Design Codes Manual — 477 .2 Rolled Steel Channels (ISJC. are available.). The following example with explanations will be helpful in understanding the input procedure: At present there is no standard way to define the local y and z axes for an angle section.g. etc.. with or without spacing between them.4 of this manual.12. D ISJC125. The letter D in front of the section name will specify a double channel (e. D ISMC75. 10 TO 20 BY 2 TA ST ISMC125 12 TA ST ISLC300 11C..2.12. ISLC and ISMC) All these shapes are available as listed in ISI section handbook.20 TO 30 TA ST ISLB325 Note: In case of two identical beams. 1 TO 5 TA ST ISHB400A 11C. the heavier beam is designated with an ‘A” on the end (e. 21 22 24 TA D ISLC225 11C.12. etc. The standard section has local axis system as illustrated in Fig.3 Double Channels Back to back double channels. ISHB400 A. Designation of the channels are per the scheme used by ISI.).4 Rolled Steel Angles Both rolled steel equal angles and unequal angles are available for use in the STAAD implementation of ISI steel tables.g. 5 23 27 TA SD ISA75X50X6 11C.e. The following example illustrates the designated method..Steel Design per IS 800 .11C. the minor axis corresponding to the V-V axis specified in the steel tables. of 20 in current length units Only code checking and no member selection will be performed if this type of specification is used.6 Rolled Tees (ISHT. use PIP followed by the numerical value of diameter and thickness of the section in mm omitting the decimal section of the value provided for diameter.12.Pro . 10 15 TA ST PIP 213. respectively. of 25 and inside dia. 14 TO 20 TA LD ISA50X30X5 SP 1. The following example will illustrate the designation. in front of the angle size.12.0ID 20. In case of an equal angle either LD or SD will serve the purpose. For example. pipe with 3. ISST.5 Double Angles Short leg back-to-back or long leg back-to-back double angles can be specified by inputting the word SD or LD. Indian Codes . For example. Many engineers are familiar with a convention used by some other programs in which the local y-axis is the minor axis.1984 This specification has the local z-axis (i.12.2 specifies a 213 mm dia.0 specifies a pipe with outside dia. ISLT and ISJT) All the rolled tee sections are available for input as they are specified in the ISI handbook.7 Pipes (Circular Hollow Sections) To designate circular hollow sections from ISI tables.2 mm wall thickness Circular pipe sections can also be specified by providing the outside and inside diameters of the section. 1 TO 9 TA ST PIPE OD 25. 478 — STAAD. STAAD provides for this convention by accepting the command: 54 55 56 TA RA ISA50X30X6 Hint: RA denotes reverse angle 11C. 1 2 5 8 TA ST ISNT100 67 68 TA ST ISST250 11C. 11C.5 is a tube that has a height of 8. Web plate width in mm.12. A. International Design Codes Manual — 479 .0 WT 6. a width of 6.5. B. The following example with explanations will be helpful in understanding the input procedure. Plate and angle girder symbol. Width and Thickness) and not by any table designations.12.9 Plate And Angle Girders (With Flange Plates) All plate and angle grinders (with flange plates) are available as listed in ISI section handbook.11C. like pipes. 6 TA ST TUBE DT 8. 15 TO 25 TA ST TUB 160808 Tubes.8 Tubes (Rectangular or Square Hollow Sections) Designation of tubes from the ISI steel table is illustrated below. Web plate thickness in mm. Note: Only code checking and no member selection is performed for TUBE sections specified this way. can also be input by their dimensions (Height.0 TH 0. C. and a wall thickness of 0. For example. 12. all in mm. Indian Codes . The following example with explanations will be helpful in understanding the input procedure. Joist Designation IW450 = ISWB450 B. Constant (always X). A. since the lighter ISWB600 is more efficient. A X B X t. Top flange plate thickness in mm. Flange angle. Bottom flange plate thickness in mm.1984 D. 480 — STAAD. Note: D = 0 for no plate. F. E. Top flange channel designation: 350 = ISMC350 C. Flange plate thickness in mm. Angle 150X150X18 200X100X15 200X150X18 200X200X18 11C. D. Table 11C. Flange plate width in mm.10 Single Joist with Channels and Plates on the Flanges to be Used as Girders All single joist with channel and plates on the flanges to be used as girders are available as listed in ISI section handbook.Steel Design per IS 800 .11C.2-Flange angle key Symbol A B C E E. Note: The heavier ISWB600 has been omitted.Pro . implies single lacing with welded connection 4. Lacing b. implies double lacing with welded connection 5. Note: Once a parameter is specified.1.0 mm Center of gravity of the channel. This is the way STAAD works for all codes. Table 11C. Table 11C. This parameter is used when member properties are defined through user provided table using GENERAL option. Batten Double channel sections (back-to-back and face-to-face) can be joined either by lacing or by batten plates having riveted or welded connection. implies batten with riveted connection 6. Nominal diameter of rivet DBL 20 mm International Design Codes Manual — 481 . These parameters will have to be provided in unit NEW MMS along with parameters defined in Table 11C.11C.13 Column With Lacings And Battens For columns with large loads it is desirable to build rolled sections at a distance and interconnect them.3 gives the parameters that are required for Lacing or batten design. The joining of element sections is done by two ways: a. implies single lacing with riveted connection 2. its value stays at that specified number until it is specified again. Parameter Name CTYPE Default Value Description 1 Type of joining 1. implies double lacing with riveted connection 3. implies batten with welded connection COG 0.3-Parameters used in Indian Lacing or Batten steel member design. 11C. Minimum thickness of weld Allowable welding stress THETA 50 degree WMIN WSTR 6 mm 108 N/mm 2 482 — STAAD. It should lie between 40 degree and 70 degree. Angle of inclination of lacing bars.0 Used when member properties are defined through user provided table using GENERAL option. This parameter is used when member properties are defined through user provided table using GENERAL option. EDIST 32 mm (Rivetted Connection) 25 mm (Welded Connection) Edge Distance. 1. double channel back-to-back. FVB FYB SPA 100 N/mm 2 300 N/mm 2 0.Pro . double channel face-to-face. Indian Codes .1984 Parameter Name DCFR Default Value Description 0.0 mm Allowable shear stress in rivet Allowable bearing stress in rivet Spacing between double channels. 0.Steel Design per IS 800 . 2 Allowable Stresses The member design and code checking in STAAD are based upon the allowable stress design method as per IS:802 (1995).1 Axial Stress Tensile Stress The allowable tensile stress. This section discusses the salient features of the allowable stresses specified by IS:802 and implemented in STAAD. as calculated in STAAD as per IS:802 is described below. Thus. the permissible stress in axial tension. Members are proportioned to resist the design loads without exceeding the allowable stresses and the most economic section is selected on the basis of least weight criteria. It is a method for proportioning structural members using design loads and forces.Pro is capable of performing steel design based on the Indian code IS 802 1995 Use of Structural Steel in Overhead Transmission Line Towers . Indian Codes .Steel Design per IS 802 STAAD. allowable stresses. 11D.Code of Practice. Design of members per IS 802 requires the STAAD Indian Design Codes SELECT Code Pack.11D. and design limitations for the appropriate material under service conditions. 11D. Two major failure modes are recognized: failure by overstressing. The design philosophy and procedural logistics for member selection and code checking are based upon the principles of allowable stress design. The estimated tensile stresses on the net effective sectional area in various members.1 General Comments This section presents some general statements regarding the implementation of Indian Standard code of practice (IS:802-1995 – Part 1) for structural steel design for overhead transmission line towers in STAAD. multiplied by the appropriate factor of safety shall not exceed minimum guaranteed yield stress of the material. σ in MPa on the net effective area of the sections at shall not exceed σat = Fy Where: F = minimum yield stress of steel in Mpa y International Design Codes Manual — 483 . and failure by stability considerations. The code checking part of the program checks stability and strength requirements and reports the critical loading condition and the governing code criteria. 11D.2. The flowing sections describe the salient features of the allowable stresses being calculated and the stability criteria being used. 11D. Condition: when (b/t) > 378/√Fy The equations in condition 1 shall be used. E = modulus of elasticity of steel in N/mm 2 KL/r = largest effective slenderness ratio of any unbraced segment of the member. and R = appropriate radius of gyration in cm.0. 11D. the allowable compressive stress is (in N/mm 2) Fa = π2 E/(KL/r)2 II.0. Condition: when (b/t) ≤ [ (b/t)lim = 210/√Fy ]: i. Mpa y K = restraint factor. When KL/r ≤ Cc. b = distance from edge of the fillet to the extreme fibre in mm.550/(b/t) Where: F = allowable unit stress in compression.5[(KL/r)/Cc]2 } ii. Note: The maximum permissible value of b/t for any type of steel shall not exceed 25.677 . and t = thickness of flange in mm. Indian Codes . Condition: when (b/t)lim < (b/t) ≤ 378/√Fy : The equations in condition 1 shall be used.Steel Design per IS 802 Compressive Stress The estimated compressive stresses in various members multiplied by the appropriate factor of safety shall not exceed the value given by the formulae described below. substituting for F the value F given by: y cr Fcr = Fy [1.677·(b/t)/(b/t)lim] III. substituting for F the value F given by: y cr Fcr = 65. Following are the default values used in STAAD: 484 — STAAD.3 Stability Requirements Slenderness ratios are calculated for all members and checked against the appropriate maximum values.Pro . L = unbraced length of the compression member in cm. Mpa a F = minimum guaranteed yield stress of the material. I. the allowable compressive stress is (in N/mm 2) Fa = Fy {1 . When KL/r > Cc. 3.5L/r 5 L/r 6 28.6 + 0.75L/r 4 60 + 0.762L/r International Design Codes Manual — 485 .1-Slenderness ratio limits of compression members Type of Member Slenderness Limit 120 Leg Members.2-Compression slenderness ratio calculation depending on ELA parameter ELA Value 1 Type of Member Calculation of KL/r L/r Leg sections or joint members bolted at connections in both faces Members with concentric loading at both ends of the unsupported panel with values of L/r up to and including 120 Member with concentric loading at one end and normal eccentricities at the other end of the unsupported panel for value of L/r up to and including 120 Members with normal framing eccentricities at both ends of the unsupported panel for values of L/r up to and including 120 Member unrestrained against rotation at both ends of the unsupported panel for value of L/r from 120 to 200 Members partially restrained against rotation at one end of the unsupported panel for values of L/r over 120 and up to and including 225 2 L/r 3 30 + 0.11D. ground wire peak member and lower members of cross arms in compression Other members carrying computed stress Redundant members and those carrying nominal stresses 200 250 Slenderness ratios of compression members are determined as follows: Table 11D.1 Compression Member Table 11D. the critical condition. In addition. 11D.1 Design Steps The following are the steps used by the program in member design: 486 — STAAD. Using TRACK 9 option calculation steps are also printed. The code checking output labels the members as PASSed or FAILed.48. Refer to Section 2.4 Minimum Thickness Requirement As per Clause7.2 Tension Members Slenderness ratio KL/r of a member carrying axial tension only.1 of IS: 802-1995 minimum thickness of different tower members shall be as follows: Members Minimum Thickness (mm) Galvanized Leg Members.2 of the Technical Reference Manual for details the specification of the Code Checking command.11D. ground wire peak member and lower members of cross arms in compression Other members 5 Painted 6 4 5 11D.3.2 + 0.615L/r Members partially restrained against rotation at both ends of the unsupported panel for values of L/r over 120 and up to and including 250 If the value for ELA is given in the input for any particular member is such that condition for L/r ratio to fall within the specified range is not satisfied.5 of the Technical Reference Manual for general information on Code Checking. Axial forces at two ends of the members are utilized for the code checking calculations. governing load case. 11D. STAAD goes on by the usual way of finding slenderness ratio using KL/r formula.Pro . The code checking is based on the IS:802 (1995) requirements. location (distance from the start) and magnitudes of the governing forces are also printed out.Steel Design per IS 802 ELA Value 7 Type of Member Calculation of KL/r 46. Refer to Section 5. Indian Codes .5.5 Code Checking The purpose of code checking is to verify whether the specified section is capable of satisfying applicable design code requirements. 11D. shall not exceed 400. the member has passed the check. If PROFILE parameter is provided. The ratio for actual stress to allowable stress. Member selection may be performed with all angle or channel sections and user provided tables.7 Member Selection by Optimization Steel section selection of the entire structure may be optimized.6 Member Selection STAAD is capable of performing design operations on specified members. 11D. This method requires substantial computer time and hence should be used with caution. The process of MEMBER SELECTION may be controlled using the parameters listed in Table 9C. Depending upon whether the member is under tension or compression the slenderness ratio of the member is calculated. This calculated ratio is checked against allowable slenderness ratio. Thickness of the member (maximum of web and flange thicknesses) is checked against minimum allowable thickness. whose properties are originally provided from user specified table. the lightest section.4 of the Technical Reference Manual for additional details. will be limited to sections in the user provided table. Up to three (3) profiles may be provided for any member with a section being selected from each one. Once an analysis has been performed.1. Allowable axial and tensile stresses are calculated. depending upon whether the member is painted or galvanized.6 of the Technical Reference Manual for general information on Member Selection. that is. the program can select the most economical section. the search for the lightest section is restricted to that profile. The optimization is based on member stiffness contributions and corresponding force distributions. Selection of members.0 or user defined value. Actual axial stress in the member is calculated. The section selected will be of the same type (either angle or channel) as originally specified by the user. 2. International Design Codes Manual — 487 .48. Number of bolts required for the critical load case is calculated.48.3. Refer to Section 5. which satisfies the applicable code requirements. Refer to Section 5. 4. if less than 1.3 of the Technical Reference Manual for details the specification of the Member Selection command. An optimum member size is determined through successive analysis/design iterations. the program determines whether the member is under compression or tension for the load case under consideration. Refer to Section 2. the net section factor is calculated by the program itself (See "Calculation of Net Section Factor" on page 493). 3. 11D. If the slenderness criterion is fulfilled check against allowable stress is performed. The optimization method utilizes a state-of-the -art numerical technique which requires automatic multiple analysis. If the minimum thickness criterion is fulfilled. If the member is under tension and there is no user defined net section factor (NSF). It may be noted that the parameters DMAX and DMIN may be used to specify member depth constraints for selection. 0 | 488 — STAAD.Steel Design per IS 802 11D.9 # BOLT = 6 FYB = 436.0 | | C = 1.6 | | * |<---LENGTH (ME= 1.8 Tabulated Results of Steel Design An example of a TRACK 2.4 | | L/R-Z = 87.4 | |************* RZ = 2.0 output for a compression member is shown here: STAAD.9 BOLT CAP = 24.0 | | | | | |PARAMETER BOLTING STRESSES | |IN NEWT MM IN NEWT MM| |--------------------------------------| | L/R-Y = 40.80 --->| RY = 4.1 | | IS-802 * =============================== ==| |== SY = 38.0 FVB = 218.Pro .PRO CODE CHECKING .0 | | LEG = 1.5 BOLT DIA = 12 MM FA = 188.0 | | FYLD = 250.7 | |DESIGN CODE * | | | | AZ = 5.11D.0 | | GALVA = 0.( 802) v1.| |MEMBER 8 * | INDIAN SECTIONS | | | AX = 17.66 KN fa = 80.7 | | KL/R = 87. Indian Codes .0 | | * | ST ISA125x95x8 | | | --Z AY = 6.8 | | * SZ = 16.0 IS- ******************************************** |-------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN CM UNIT | | * |=============================| ==| |== ----------. ALLOWABLE THICKNESS : 6.94 EQN.0 MM RESULT : PASS CHECK FOR SLENDERNESS RATIO --------------------------VALUE OF L/r : 87.| ELA | NSF | = | = | | 1. USED TO FIND KL/r : L/r ACTUAL VALUE OF KL/r : 87.94 ALLOWABLE KL/r : 120.0 1.0 MM ACTUAL THICKNESS : 8.00 RESULT : PASS CALCULATION OF ALLOWABLE STRESS International Design Codes Manual — 489 .0 |**************************************************************************| |* *| |* DESIGN SUMMARY ( KN-METR) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS COMPRESSION 0.428 1 | | 137.0 0.0 also adds the following set of calculation details: DETAILS OF CALCULATION ---------------------CHECK FOR MINIMUM THICKNESS --------------------------TYPE : PAINTED MIN.13 C 0.00 | |* *| |**************************************************************************| | | |-------------------------------------------------------------------------| Using TRACK 9.0 0. 86 KN BOLT CAP : 24.14159265*3. Indian Codes . Use specified NSF value 1. its value stays at that specified number until it is specified again.WEB THICKNESS .41 MPA CHECK AGAINST PERMISSIBLE STRESS -------------------------------LOAD NO.14159265*E : 127.3-Indian Steel Design IS 802 Parameters Parameter Name CNSF Default Value Description 0.0 : 108. Net section factor will be calculated.16 / 1700.8. 24 BOLTING ------BOLT DIA : 12 MM SHEARING CAP : 24.(0.66 KN BEARING CAP : 41.0 This parameter indicates whether user has defined the net section factor or the program will calculate it.28 (b/t)cal : 13. This is the way STAAD works for all codes. 490 — STAAD.677 .0 9.5*(KL/r/Cc)*(KL/r/Cc))*Fcr : 188.Pro .0 .9 Design Parameters Note: Once a parameter is specified. 0. : 1 DESIGN AXIAL FORCE : 137131.67 MPA RESULT : PASS EXAMPLE PROBLEM NO. OF BOLTS REQD.0 MM (b/t)lim : 210/sqrt(fy) : 13.91 (b/t)cal <= (b/t)lim (modified) AND KL/r <= Cc Fcr : (1. Table 11D.66 KN NO.50 (b/t)cal > (b/t)lim (b/t)lim (modified) : 378/sqrt(fy) : 23. STRESS : 137131.53 b : LENGTH OF LEG .677*(b/t)cal/(b/t)lim))*fy : 247.18 MPA ALLOWABLE AXIAL COMP.11D.ROOT RADIUS : 125. STRESS : (1-0.Steel Design per IS 802 --------------------------------CRITICAL CONDITION : COMPRESSION Cc : sqrt(2*3.0 : 80.1 -PAGE NO. : 6 ************** END OF TABULATED RESULT OF DESIGN ************** 11D.16 N ACTUAL AXIAL COMP. Allowable shear stress in bolt Allowable bearing stress in bolt Yield Strength of steel Thickness of gusset plate. Pair of angle placed back-toback connected by only one leg of each angle to the same side of a gusset plate DBL 12 mm Diameter of bolt for calculation of number of bolts and net section factor. this is major axis. 0. This parameter indicates what type of end conditions is to be used. Usually. KZ 1.3.0 cm. Maximum allowable depth.0 cm.Parameter Name DANGLE Default Value Description 0. 1.0 FVB FYB FYLD GUSSET 218 MPA 436 MPA 250 MPA 5 mm KY 1. Double angle placed back-toback and connected to each side of a gusset plate 1.0 This parameter indicates how the pair of angles are connected to each other. Refer Section 9C. 0.0 International Design Codes Manual — 491 . Usually. Minimum of the thicknesses of the gusset plate and the leg is used for calculation of the capacity of bolt in bearing DMAX DMIN ELA 100.0 K value in local y-axis. Minimum allowable depth. this is minor axis. This is required to find whether the angle is in single or double shear and the net section factor. K value in local z-axis. 0. Tension members (KL/r = 400) 10.Pro . The angle is connected by shorter leg 1.0 Unbraced length in local z-axis to calculate slenderness ratio. The angle is connected by longer leg LY Member Length Member Length 1.0 Net section factor for tension members 492 — STAAD. Indian Codes .Steel Design per IS 802 Parameter Name LEG Default Value Description 1. Ground wire peak and lower members of cross arms in compression (KL/r = 120) 2.11D. For this case KY and KZ values are must to find actual KL/r ratio of the member. 1. Unbraced length in local z-axis to calculate slenderness ratio.0 This parameter is meant for plain angles. Leg. Type of member to find allowable Kl/r for slenderness calculations for members. Redundant members and members carrying nominal stresses (KL/r = 250) 4. Do not perform KL/r check Any value greater than 10. LZ MAIN NSF 1.0 indicates user defined allowable KL/r ratio. Members carrying computed stress (KL/r = 200) 3. Parameter Name NHL Default Value Description 0. this parameter is to be defined.5 mm. net where: a. Default value is one bolt width plus 1. it is the ratio of the net effective area.0 mm Deduction for holes. For an angle section. A . TRACK 0. 11D. Suppress critical member stresses 1. Print all critical member stresses 2.0. Print expanded output.0 Level of output detail: 0. Pair of angles placed back-to-back connected by only one leg of each angle to the same side of a gusset plate International Design Codes Manual — 493 .10 Calculation of Net Section Factor The procedure for calculating the net section factor for an angle section is as follows: l For a channel section. to the gross area. diagonal or zigzag line across the member is different from the default value. net section factor is taken to be 1. Print design calculations along with expanded output (not available in GUI input). Single angle connected by only one leg Anet = A1 + A2 · K1 Where: A = net cross-sectional area of the connected leg 1 l A = gross cross-sectional area of the unconnected leg 2 K1 = 3·A1 /(3·A1 + A2 ) The area of a leg of an angle = Thickness of angle x (length of leg – 0. If the area of holes cut by any straight. 9.5x thickness of leg) b. 494 — STAAD.5x thickness of leg) c. Indian Codes . Design some members as per IS-802 and show detailed calculation steps for the critical loading condition. 28 A transmission line tower is subjected to different loading conditions. Double angles placed back-to-back and connected to each side of a gusset plate A net = gross area minus the deduction for holes 11D.11D.11 Example Problem No.Pro .Steel Design per IS 802 Anet = A1 + A2 · K1 Where: A = net cross-sectional area of the connected leg 1 A = gross cross-sectional area of the unconnected leg 2 K1 = 5·A1 /(5·A1 + A2 ) The area of a leg of an angle = Thickness of angle x (length of leg – 0. 11 13 14. 18 20 12. 28 1. 15 17 18. 21 15 5.2 STAAD Input File This input file is included with the program as C:\SProV8i\STAAD\Examp\Ind\Examp28. 8 9 10.2.4 24 -1. 13 -2.2.8.4 24 1.2.6.2. 6 2. 22 1.2 30 1. 37 -2 15 -2. 2 1. 25 2. 11 -3 0 3. 51 -4.2. 55 -7. 24 2.1 Given End Condition = Members with normal framing eccentricities at both ends of the unsupported panel for values of L/r up to and including 120 Diameter of the bolt = 16 mm Thickness of the gusset plate = 8 mm Net Section Factor is to be calculated.2.4.4. 8 1.2 30 -1. 43 1.4.2 30 -1.11D.4 9 2. 32 -1.2.4.2 27 1. 7 8 9.6 21 1.4 24 -1.2 27 -1.11.4 24 1. 34 -2. 35 2.4. 16 18 19.2 27 1. 36 -2. 5 2.8.6 21 -1. 2 3 4. 3 2. 26 20 10. 50 4. 11D.2 33 1.2. 23 2. 13 15 16.2 33 -1. 15 -2.2. 20 1. 18 -1. 14 -2.6.6 6 -2. 53 -4. 9 1. 61 0 35 0.2 33 1. 17 -2 15 2.2. 49 7.2 30 1. 57 1.2 27 -1. 47 4.2 27 -1.2. 33 -2.6.8 3 -2.2 27 -1. 4 2.2. 19 -1.6 6 -2. 52 -7. 4 5 6.2.2.2 27 1.8 18 1.2 27 -1. 30 1.2.6. 25 19 9. MEMBER INCIDENCES 1 1 3. 29 1.2. 42 -1.8.6 6 2.2.6 21 1. 12 14 15.4 9 -2.2 33 -1. 10 11 13.2. 48 4. 31 -3 0 -3.2. 22 16 6.2 30 1.2 30 -1.6. 58 -1. 26 2.8. 16 -2.2. STAAD TRUSS INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 3 0 3.4 9 -2. 27 2 15 -2.2 12 -2. 12 -1.2.6 21 -1.8.4. 46 7.8 18 -1.2 30 -1. 5 6 7.2.8 3 2. 59 1.6 6 2. 7 2 15 2.2 27 1.8 3 2.8. 19 13 3. 45 4.2. 40 -1.6.8 3 -2. 39 -1. 38 -1. 21 3 0 -3.4 9 2.2 27 1.2.6. 60 -1. 23 17 7.2 12 -2.2 27 1. 17 19 20.2 30 1. 9 10 2.8 18 -1.2. 3 4 5.11. 6 7 8.6.8. 20 14 4. 44 -1.2.2 12 2.2 27 -1. 24 18 8. 54 -4.4. 56 -4.2.std.2 12 2. International Design Codes Manual — 495 .4. 10 1.8.8 18 1. 14 16 17. 41 1.2. 200 53 56. 190 51 12. 77 9 28. 159 12 44. 122 37 17. 165 46 45. 199 44 54. 44 20 2. 32 14 5. 95 27 37. 46 21 23. 108 26 37. 138 38 17. 81 2 30. 85 35 36. 120 35 15. 168 50 48. 68 4 25. 184 47 48. 89 39 40. 181 2 47. 51 27 28. 92 24 34. 118 33 13. 78 9 30. 93 25 35. 123 38 18. 174 46 49. 198 55 54. 43 20 9. 67 23 4. 83 33 34. 119 34 14. 47 23 24. 158 44 22. 105 25 34. 64 1 23. 148 22 43. 42 19 10. 84 34 35. 185 50 45. 144 32 20. 31 3 14. 182 22 45. 34 15 6. 137 37 18. 183 2 48. 147 2 41. 35 16 5. 58 6 26. 171 49 48. 177 50 46. 90 40 32. 141 39 20. 164 47 46. 196 54 32. 69 5 24. 86 36 37. 56 4 24. 175 45 48. 99 22 32. 37 17 6. 140 39 18. 145 32 44. 154 42 2. 134 36 15.Pro . 70 5 26. 101 31 23. 178 43 47. 71 6 25. 129 33 14. 100 21 33. 153 12 41. 57 5 25. 126 32 12. 192 52 51.11D. 49 25 26. 143 40 12. 53 29 30. 136 37 16. 203 42 56. 102 23 34. 96 28 38. 112 28 39. 63 2 22. 195 56 54. 131 34 15. 33 15 4. 30 13 4. 109 27 36. 104 24 35. 45 12 10. 194 44 56. 79 10 29. 124 39 19.Steel Design per IS 802 27 12 2. 127 31 13. 151 43 44. 28 11 3. 97 29 39. Indian Codes . 52 28 29. 173 47 50. 115 30 39. 55 3 23. 91 23 33. 128 11 33. 130 13 34. 59 7 27. 135 36 17. 114 29 40. 157 43 32. 197 56 55. 87 37 38. 75 8 27. 74 7 28. 38 17 8. 161 41 47. 149 42 41. 61 9 29. 170 50 49. 163 45 2. 36 16 7. 139 38 19. 98 30 40. 72 6 27. 60 8 28. 62 10 30. 40 18 9. 201 52 55. 162 47 45. 94 26 36. 187 48 46. 41 19 8. 179 47 49. 73 7 26. 132 35 14. 54 30 22. 65 21 3. 107 26 35. 496 — STAAD. 117 22 40. 113 29 38. 188 42 53. 133 35 16. 172 43 48. 176 41 50. 121 36 16. 142 40 19. 88 38 39. 116 30 32. 110 27 38. 155 22 41. 166 41 45. 106 25 36. 80 10 22. 156 43 2. 82 31 33. 39 18 7. 146 12 42. 111 28 37. 191 53 52. 29 1 13. 189 53 51. 48 24 25. 160 32 42. 167 43 50. 125 40 20. 193 42 51. 150 41 43. 202 51 54. 50 26 27. 66 3 24. 152 44 42. 186 45 49. 180 22 50. 169 48 22. 103 33 24. 76 8 29. 253 44 41. 243 37 7. 224 42 60. 205 44 53. 250 20 30. 211 53 54. 229 43 57. 247 39 9. 228 43 60. 230 41 59. 246 18 28.3 ALL DENSITY 76.01 19 TO 26 28 TO 45 55 TO 62 64 TO 81 91 TO 98 100 TO 125 127 TO 144 155 156 159 160 223 224 229 230 235 TO 250 TA ST ISA150X150X10 27 63 99 126 149 TO 154 157 158 161 TO 214 219 TO 222 225 TO 228 231 232 251 252 TO 258 TA ST ISA80X50X6 CONSTANTS E 2. 240 15 25. 217 41 57. 239 35 5. 225 42 57. 245 38 8. 214 54 52.05E+008 ALL POISSON 0. 238 14 24. 256 58 61. 244 17 27. 210 12 54. 226 41 58. 242 16 26. 213 51 55. 255 60 61.8195 ALL ALPHA 6. 257 57 61. 223 44 58. 207 32 56. 236 13 23. 254 43 42.204 56 52. 206 53 55. 231 60 57. 219 60 59. 220 59 57. 221 57 58. 227 44 59. MEMBER PROPERTY INDIAN 1 TO 18 46 TO 54 82 TO 90 145 TO 148 215 TO 218 TA LD ISA200X150X18 SP 0. 248 19 29. 209 32 51. 216 42 58. 249 40 10. 251 32 2. 212 56 51. 252 22 12. 235 33 3. 258 59 61. 215 44 60.5E-006 ALL SUPPORTS 1 11 21 31 FIXED UNIT METER KG LOAD 1 VERT SELFWEIGHT Y -1 JOINT LOAD 61 FX 732 46 49 52 55 FX 153 61 FX 1280 FY -1016 FZ 160 46 49 52 55 FX 9006 FY -7844 FZ 1968 2 12 22 32 FX 4503 FY -3937 FZ 1968 LOAD 2 GWBC SELFWEIGHT Y -1 JOINT LOAD 61 FX 549 International Design Codes Manual — 497 . 218 43 59. 241 36 6. 222 58 60. 237 34 4. 232 59 58. 208 12 53. 11.0 MEMB 28 DBL 16 ALL GUSSET 8 ALL TRACK 9 ALL CHECK CODE MEMB 1 28 FINISH 11D. Indian Codes .Steel Design per IS 802 46 49 52 55 FX 1148 61 FX 515 FY -762 FZ 2342 46 49 52 55 FX 6755 FY -5906 2 12 22 32 FX 3378 FY -2953 LOAD 3 LEFT PCBC SELFWEIGHT Y -1 JOINT LOAD 61 FX 549 46 49 52 55 FX 1148 61 FX 960 FY -762 46 49 FX 6755 FY -5906 52 55 FX 4211 FY -4551 FZ 13293 2 12 22 32 FX 3378 FY -2953 LOAD 4 RIGHT PCBC SELFWEIGHT Y -1 JOINT LOAD 61 FX 549 46 49 52 55 FX 1148 61 FX 960 FY -762 52 55 FX 6755 FY -5906 46 49 FX 4211 FY -4551 FZ 13293 2 12 22 32 FX 3378 FY -2953 PERFORM ANALYSIS UNIT NEW MMS PARAMETER CODE IS802 LY 2800 MEMB 28 LZ 2800 MEMB 28 MAIN 1.0 member code check follows: 498 — STAAD.0 MEMB 1 ELA 4 MEMB 1 CNSF 1.3 Output A portion of the output for the TRACK 9.Pro .11D. 0 | | LEG = 1.0 IS-802) ******************************************** |-------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN CM UNIT | | * |=============================| ==||== ----------.0 | | * | LD ISA200X150X18 | || --Z AY = 48.( v1.6 BOLT DIA = 16 MM FA = 195.01 --->| RY = 6.0 FVB = 218.3 | | | | | |PARAMETER BOLTING STRESSES | |IN NEWT MM IN NEWT MM| |--------------------------------------| | L/R-Y = 48.PRO CODE CHECKING .0 | |DESIGN CODE * | | || AZ = 36.2 | |************* RZ = 6.0 | | ELA = 4.0 | International Design Codes Manual — 499 .3 # BOLT = 32 FYB = 436.6 | | * |<---LENGTH (ME= 3.STAAD.0 | | IS-802 * |-----------------------------| || SY = 297.1 | | L/R-Z = 47.| |MEMBER 1 * | INDIAN SECTIONS | || AX = 120.0 | | FYLD = 250.2 | | KL/R = 84.7 BOLT CAP = 55.81 KN fa = 145.3 | | * SZ = 350.0 | | GALVA = 0.0 | | NSF = 1.0 | | C = 1. 26 C 0.24 b : LENGTH OF LEG .0 0.00 | |* *| |**************************************************************************| | | |-------------------------------------------------------------------------| STAAD TRUSS -PAGE NO.Pro . Indian Codes .0 0.0 MM ACTUAL THICKNESS : 18.ROOT RADIUS 500 — STAAD.14159265*3.0 MM RESULT : PASS CHECK FOR SLENDERNESS RATIO --------------------------VALUE OF L/r : 48.11D. USED TO FIND KL/r : 60.WEB THICKNESS .14159265*E : 127.0 + 0. 5 DETAILS OF CALCULATION ---------------------CHECK FOR MINIMUM THICKNESS --------------------------TYPE : PAINTED MIN.5*L/r ACTUAL VALUE OF KL/r : 84.63 EQN.00 RESULT : PASS CALCULATION OF ALLOWABLE STRESS --------------------------------CRITICAL CONDITION : COMPRESSION Cc : sqrt(2*3.744 1 | | 1742.31 ALLOWABLE KL/r : 120. ALLOWABLE THICKNESS : 6.Steel Design per IS 802 | | |**************************************************************************| |* *| |* DESIGN SUMMARY ( KN-METR) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS COMPRESSION 0. OF BOLTS REQD.7 | | * SZ = 44.0 | |DESIGN CODE * | | | | AZ = 10.0 | | IS-802 * =============================== ==| |== SY = 95.: 200.53 --->| RY = 5.81 KN NO.0 ******************************************** |-------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN CM UNIT | | * |=============================| ==| |== ----------.2 | | * | ST ISA150X150X10 | | | --Z AY = 10.15. STRESS :1742259.0 MM (b/t)lim : 210/sqrt(fy) : 13.28 (b/t)cal <= (b/t)lim AND KL/r <= Cc ALLOWABLE AXIAL COMP. 7 STAAD. : 1 DESIGN AXIAL FORCE : 1742259.0 .5*(KL/r/Cc)*(KL/r/Cc))*fy : 195.28 (b/t)cal : 9.18.( IS-802) v1.PRO CODE CHECKING .0 : 167.0 : 145.75 N ACTUAL AXIAL COMP.0 .19 MPA RESULT : PASS STAAD TRUSS -PAGE NO.8 | | * |<---LENGTH (ME= 6.66 KN BEARING CAP : 55.81 KN BOLT CAP : 55. 6 BOLTING ------BOLT DIA : 16 MM SHEARING CAP : 87.75 / 12000.| |MEMBER 28 * | INDIAN SECTIONS | | | AX = 29. : 32 STAAD TRUSS -PAGE NO.9 | |************* RZ = 3.07 MPA CHECK AGAINST PERMISSIBLE STRESS -------------------------------LOAD NO.0 | | | International Design Codes Manual — 501 . STRESS : (1-0. 5 = 249.0 6.0 | | FYLD = 250.0 | | GALVA = 0.0 | | ELA = 1.194 3 | | 112.11D.0 = 48.0 0.Pro .0 | | C = 1.83 KN 3 -FA fa |**************************************************************************| |* *| |* DESIGN SUMMARY ( KN-METR) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS TENSION 0.9 | | L/R-Z = 94.86 T 0.5 | | KL/R = 94.0 FVB = 218.0 | | NSF = 0.0 | | LEG = 1.Steel Design per IS 802 | | |PARAMETER STRESSES | |IN NEWT MM NEWT MM| |-------------------------| | L/R-Y = 47.0 FYB = 436.8 | | | BOLTING IN ------------BOLT DIA = 16 MM BOLT CAP = # BOLT = 43. Indian Codes .53 | |* *| |**************************************************************************| | | 502 — STAAD. USED TO FIND KL/r : K*L/r ACTUAL VALUE OF KL/r : 93.797 ) : 48.0 MM RESULT : PASS CHECK FOR SLENDERNESS RATIO --------------------------VALUE OF L/r : 93.51 MPA RESULT : PASS BOLTING ------BOLT DIA : 16 MM SHEARING CAP : 43.96 EQN.94 MPA CHECK AGAINST PERMISSIBLE STRESS -------------------------------LOAD NO.83 KN NO. OF BOLTS REQD.|-------------------------------------------------------------------------| STAAD TRUSS -PAGE NO. : 3 STAAD TRUSS -PAGE NO.96 ALLOWABLE KL/r : 400. 9 ************** END OF TABULATED RESULT OF DESIGN ************** International Design Codes Manual — 503 .91 N ACTUAL AXIAL TENSILE STRESS : 112855.0 MM ACTUAL THICKNESS : 10. : 3 DESIGN AXIAL FORCE : 112855.91 / ( 2920.0*0.00 RESULT : PASS CALCULATION OF ALLOWABLE STRESS --------------------------------CRITICAL CONDITION : TENSION ALLOWABLE AXIAL TENSILE STRESS : 249.83 KN BEARING CAP : 55. ALLOWABLE THICKNESS : 6.81 KN BOLT CAP : 43. 8 DETAILS OF CALCULATION ---------------------CHECK FOR MINIMUM THICKNESS --------------------------TYPE : PAINTED MIN. 504 — STAAD.Pro . Design of members per IS 801 requires the STAAD Indian Design Codes SELECT Code Pack. including revisions dated May.2.2 Design Procedure The program calculates effective section properties in accordance with Clause 5. The program allows design of single (noncomposite) members in tension.6. STAAD. The properties listed in the tables are gross section properties.1 International Design Codes Manual — 505 . l l The program will check member strength in accordance with Clause 6 of the Standard as follows: 11E. 11E. Maximum Section Depths. The Tables are currently available for the following shapes: l Channel with Lips Channel without Lips Angle without Lips Z with Lips Hat l l l l Shape selection may be done using the member property pages of the graphical user interface (GUI) or by specifying the section designation symbol in the input file.1 Members in tension Resistance is calculated in accordance with Clauses 6. as applicable.1.3.11E.2.1 Cross-Sectional Properties The user specifies the geometry of the cross-section by selecting one of the section shape designations from the Gross Section Property Tables from IS:811-1987 (Specification for cold formed light gauge structural steel sections). Crosssectional properties and overall slenderness of members are checked for compliance with l Clause 6. shear. 11E.2. Maximum Flat Width Ratios for Elements in Compression Clause 5. Both unreduced and effective section properties are used in the design stage.3.Pro uses unreduced section properties in the structure analysis stage. Maximum Effective Slenderness Ratio for members in Compression Clause 5. 1988.1.Pro is capable of performing steel design based on the Indian code IS 801 1975 Code of practice for use of cold formed light gauge steel structural members in general building construction. Indian Codes . compression.4. as well as their combinations. bending.2.Design per Indian Cold Formed Steel Code STAAD. Cold work of forming strengthening effects has been included as an option. 0 which may be subjected to torsionalflexural buckling Clause 6.Pro . Clause 6.3 Members in compression Resistance calculations are based on Clauses: l l l Clause 6.7.3 Combined Bending and Shear in Webs.6.1 Shapes not subject to torsional-flexural buckling.1. Clause 6.3.7.4 Members in compression and bending Resistance calculations are based on Clauses: l l l All clauses for members in compression Clause 6.1.3 Laterally Unsupported Members. l l 11E.1.3 Code Checking and Member Selection The following two design modes are available: 506 — STAAD.2 Compression on flat unstiffened element.3 Singly-symmetric sections and nonsymmetrical shapes or intermittently fastened singly-symmetrical components of built-up shapes having Q < 1.7.4.1 Shear stress in webs. Indian Codes .4. Singly-symmetric shapes or Intermittently fastened singly-symmetric components of built-up shapes having Q=1. Clause 6.2 Singly-symmetric sections and nonsymmetrical shapes of open cross section or intermittently fastened singly-symmetrical components of built-up shapes having Q = 1.2 Bending stress in webs Clause 6.6. Clause 6.0 which may be subject to torsional-flexural buckling.2.2 Members in bending and shear Resistance calculations are based on Clauses: l l l Clause 6. Singly-symmetric shapes or Intermittently fastened singly-symmetric components of built-up shapes having Q<1.0 which may be subjected to torsionalflexural buckling.11E.Design per Indian Cold Formed Steel Code 11E.4.8 Cylindrical Tubular Sections.0 which may be subject to torsional-flexural buckling. Clause 6.6. 11E. Clause 6.2.2.2.1 Doubly-symmetric shapes or Shapes not subjected to torsional or torsionalflexural buckling Clause 6. l l 11E. 3 of the Technical Reference Manual for details the specification of the Member Selection command. channel. The following table contains the input parameters for specifying values of design variables and selection of design options..1-Indian cold formed steel design parameters Parameter Name CODE Default Value Description - Must be specified as IS801 Design Code to follow. See section 5.48. presents design results for that section.11E. The results are presented in a form of a PASS/FAIL identifier and a RATIO of load effect to resistance for each member checked. If no section satisfying the depth restrictions or lighter than the initial one can be found. Refer to Section 2. International Design Codes Manual — 507 . Table 11E. Refer to Section 2.48.) and.1 Code Checking The program compares the resistance of members with the applied load effects. regardless of whether it passes the code check or not. Refer to Section 5. if a suitable replacement is found.e.48. 11E. The program will then evaluate all database sections of the type initially specified (i. angle.2 of the Technical Reference Manual for details the specification of the Code Checking command.6 of the Technical Reference Manual for general information on Member Selection. The user may choose the degree of detail in the output data by setting the TRACK parameter. In addition.5 of the Technical Reference Manual for general information on Code Checking.3. Note: Once a parameter is specified. in accordance with IS:801-1975. 11E.2 Member Selection The user may request that the program search the cold formed steel shapes database (IS standard sections) for alternative members that pass the code check and meet the least weight criterion.4 Design Parameters Input for the coefficients of uniform bending must be specified. its value stays at that specified number until it is specified again. a minimum and/or maximum acceptable depth of the member may be specified.1 of the Technical Reference Manual.3. etc. Code checking is carried out for locations specified by the user via the SECTION command or the BEAM parameter. Refer to Section 5. the program leaves the member unchanged. This is the way STAAD works for all codes. See IS:801-1975. Specifies whether the cold work of forming strengthening effect should be included in resistance computation.Pro . effect should not be included 1. Indian Codes . Coefficient of equivalent uniform bending Ω .0. 6. and instead. CMY 0. Section not subject to torsional flexural buckling 1.0 BEAM When this parameter is set to 0.6.4 to 1.7.0 CWY 0. See IS:801-1975. For TRUSS members only start and end locations are designed.7. 6. See IS:8011975. the 13 location check is not conducted. See IS:801-1975. Section subject to torsional flexural buckling 508 — STAAD. 1. effect should be included CMZ 1.1 0. checking is done only at the locations specified by the SECTION command (See STAAD manual for details. Values range from 0.4 to 1. 6.11E. Used y for Combined axial load and bending design. Values range from 0. 6.1. the adequacy of the member is determined by checking a total of 13 equally spaced locations along the length of the member.Design per Indian Cold Formed Steel Code Parameter Name Default Value Description 1.85 Coefficient of equivalent uniform bending Ω .85 FLX 1 Specifies whether torsional-flexural buckling restraint is provided or is not necessary for the member.0.1 0. Used z for Combined axial load and bending design. 0 KZ 1. It is a fraction and is unit-less. Effective length factor for overall buckling in the local Z-axis. Values can range from 0.0 Effective length factor for torsional buckling. Values can range from 0.01 (for a column completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression.04 MPa (3600. KY 1. It is a fraction and is unitless. Effective length factor for overall buckling about the local Y-axis.0 International Design Codes Manual — 509 .01 (for a column completely prevented from buckling) to any user specified large value.72 kg/cm 2) Ultimate tensile strength of steel in current units.01 (for a member completely prevented from buckling) to any user specified large value.0 kg/cm 2) Yield strength of steel in current units. It is used to compute the KL/R ratio for determining the capacity in axial compression. Values can range from 0. It is a fraction and is unit-less.Parameter Name FU Default Value Description 450 MPa (4588. FYLD 353. KX 1. Indian Codes .11E.Pro . Effective length for overall buckling in the local Z-axis. It is used to compute the KL/R ratio for determining the capacity in axial compression.01 (for a member completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression. It is input in the current units of length. RATIO 1. Effective length for overall buckling in the local Y-axis. Values can range from 0. 0 – Check slenderness ratio 0 – Do not check slenderness ratio LY Member length LZ Member length MAIN 0 NSF DMAX 1. It is used to compute the KL/R ratio for determining the capacity in axial compression.0 STIFF Member Length 510 — STAAD. in the current units. Permissible ratio of actual to allowable stresses Spacing of shear stiffeners for stiffened flat webs. in current units. Net section factor for tension members Maximum allowable depth. Values can range from 0.Design per Indian Cold Formed Steel Code Parameter Name LX Default Value Description Member length Unbraced length for twisting. It is input in the current units of length. Values can range from 0. It is input in the current units of length.0 cm.01 (for a member completely prevented from buckling) to any user specified large value.01 (for a member completely prevented from torsional buckling) to any user specified large value.0 2540. 4 1. 5. and PASS/FAIL status. Prints member and material properties in addition to that printed by TRACK 1. Do not comply with 5.4 International Design Codes Manual — 511 . 0. The allowable values are: 0.4. TSA 1 Specifies whether webs of flexural members are adequately stiffened to satisfy the requirements of IS:801-1975.2. Prints only the member number. ratio. Prints the design summary in addition to that printed by TRACK 0 2.2. section name. 1.2.Parameter Name TRACK Default Value Description 0 This parameter is used to control the level of detail in which the design output is reported in the output file. Comply with 5. 512 — STAAD.Pro . Pro V8i (SELECTseries 3) (release 20. The IS 800: 2007 Code is used as the basis of this design. Slenderness 2. A brief description of some of the major capacities is described herein. STAAD compares the actual design forces with the capacities as defined by the Indian Standard Code.Pro is capable of performing steel design based on the Indian code IS 800 . Tension 4..11F. Design of members per IS 800 requires the STAAD Indian Design Codes SELECT Code Pack.Code of practice.e. Indian Codes . 1. Shear International Design Codes Manual — 513 . Section Classification 3.Steel Design per IS 800:2007 STAAD. 11F. Where: n = optional integer (i. 2) which signifies the numerical order of parameter command block (if multiple blocks are specified).07.1.1 General Comments For steel design.2007 General construction in steel . Compression 5. 11F.08) or higher are required for design per WSD. The following commands should be used to initiate design per Limit State Method of this code: PARAMETER n CODE IS800 LSD The following commands should be used to initiate design per Working Stress Method of this code: PARAMETER n CODE IS800 WSD Note: STAAD.2 Design Process The design process follows the following design checks. . 2.Pro .Pro is capable of designing I-Sections with slender webs for IS 800:2007. Combined Interaction Check All of the design check criteria are described in the following sections.8 Table 3.7 of IS 800:2007 and Table B2. This classification is a function of the geometric properties of the section as well as nature of the load applied to the member. This method requires that the flanges be non-slender elements (i. Thus local buckling becomes an important criterion..2.1. on the web is a slender element) to qualify for a valid section for design.2-(a) – (d) of the code. as defined in Table 11F. for Outstanding and Internal Elements of a section. and the slenderness ratio (L/r) of tension members shall not exceed 400.Pro V8i (SELECTseries 3) (release 20.7. 11F. 514 — STAAD. Compact. STAAD is capable of determining the section classification for the standard shapes and design the section for the critical load case accordingly. Bending 7. The IS:800-2007 code does not provide any clear guidelines about what method should be adopted for the design of slender section. refer to section 3. or Slender element sections depending upon their local buckling characteristics. The "Flange Only" methodology is used where it is assumed that flexure is taken by the flanges alone and the web will resist shear with adequate shear buckling resistance. the design will not be performed and a warning message is displayed in the output. If any of the flange elements become slender. Note: This feature requires STAAD. The design procedures are different depending on the section class. Slender Sections STAAD. 11F.1 Slenderness As per Section 3.11F. Indian Codes .08) or higher. Steel sections are classified as Plastic.Steel Design per IS 800:2007 6.2 Section Classification The IS 800: 2007 specification allows inelastic deformation of section elements. You can edit the default values through MAIN and TMAIN parameters.07. For the criteria for being included in those classes. The Section Classification is done as per section 3. Semi-Compact.e. When a design is performed. the slenderness ratio (KL/r) of compression members shall not exceed 180. the output file reports the maximum utilization ratio from all the above mentioned checks. 4 of the code.3 Tension Limit State Method The criteria governing the capacity of Tension members are based on: l Design Strength due to Yielding in Gross Section Design Strength due to Rupture of Critical Section Design Strength due to Block Shear l l STAAD calculates the tension capacity of a given member based on these three limit states. Working Stress Method The criteria governing the allowable stress from tension in members are based on Section 11. l l Note: Block shear is not checked by default. γ . is taken as 1. International Design Codes Manual — 515 . involving rupture at the section with the net effective area. and the corresponding check is done as per section 6. Clause 5. This check is made option through use of the DBS parameter. Here.1 of the code. and ATN must be supplied to the program for any member which is to be checked for block shear. This criteria is made optional by the parameter DBS.2.2. AVN. Rupture of Net Section .4. respectively.2 of the code. The limit state of yielding in the gross section is intended to prevent excessive elongation of the member.25 per Table 5. The Net Section Area may be specified through the use of the parameter NSF.to prevent excessive elongation of the member due to material yielding. The Design strength. Clause 5. ATG. γ and γ .11F.. ATG. M0 M1 per Table 5.4. AVN.1 of the code: l Yielding of Gross Section . and ATN must be supplied to the program for that member. The Design strength. involving block shear at an end connection.10 and 1. Additional design parameters AVG. is evaluated as per section 6. the number of bolts in the connection may be specified through the use of the design parameter ALPHA. The code parameter. The number of bolts in the connection may be specified through the use of the design parameter ALPHA.to prevent rupture of the net effective section area.25. The code parameters.3 of the code. are taken as 1.1 of the M1 code. is evaluated as per section 6. additional design parameters AVG. Block Shear — to prevent block shearing at the end connection. If the value of DBS is specified as 1. c or d as per clause 7. this is limited to value of Ae as described below. λ = (FYLD/Fcc)1/2 φ = 0. YY ZZ Fac = 0.4 Compression The design capacity of the section against Compressive Force. This is equal to e the gross cross sectional area.1.3.0.2 and Table 7 of IS 800:2007.5[ 1 + a(λ . Indian Codes . Limit State Method The buckling strength of the member is affected by residual stress. the strength of the members subjected to axial compression is defined by buckling class a. initial bow and accidental eccentricities of load.2 of the code. The permissive compressive stress is calculated by first determining the Buckling Class of the section per Table 10 of the code and α & α based on Table 7. In the case of slender sections. Fcd = (FYLD/γmo )/ [φ + (φ2 + λ2 ] λ = the non-dimensional slenderness factor is evaluated for each local Y and Z axis. FYLD .2 of IS 800:2007.2. Imperfection factor.Pro .1.2.Steel Design per IS 800:2007 These criteria are dependant on the steel material yield stress parameter. b.6·Fcd Where: F cd = the minimum of the values of Fcd calculated for the local Y and Z axis. for any non-slender (plastic. Working Stress Method The actual compressive stress is given by: fc = FX/Ae Where: A = The effective section area as per Clause 7. and ultimate tensile strength parameter. the guiding phenomenon is the flexural buckling. FU.2) + λ2 ] F cc = the Euler Buckling Stress. and Euler’s Buckling Stress ultimately govern compressive force capacity of the section as per clause 7.11F. To account for all these factors. Fcc = π2 ·E/(Kl/r)2 516 — STAAD. 11F. obtained from buckling class. AX. compact. or semi-compact) section class. K = the effective length factor for bending about either the local Y or Z axis. 8. respectively.2(a). r = radius of gyration about the local Y or Z axis for the section.4 of the code.1.1. Slender Sections For member with slender section under axial compression. 8.(d/tw .3. as provided in the KY and KZ parameters. e A = Gross area of section.2.2.and minor-axis directions are evaluated as per section 8.4. Working Stress Design The actual shear stress is determined about the major and minor axes. (corresponding to “Internal Element of Compression Flange”) Ae= Ag .1.4.4. Refer to clause 7.42ε) · tw2 Where: A = Effective area of section. w 11F.5 Shear The design capacities of the section against Shear Force in major. 8. Among shear buckling design methods. Simple post-critical method is adopted as per sec. FYLD = The yield strength of steel specified in the FYLD parameter. respectively: τbY = FY / AY τbZ = FZ / AZ The permissible shear stress is determined as: International Design Codes Manual — 517 . taking care of the following phenomena: l Nominal Plastic Shear Resistance Resistance to Shear Buckling l Shear area of the sections are calculated as per sec. Nominal plastic shear resistance is calculated as per sec.2 and Table 2 of IS 800:2007. design compressive strength should be calculated on area ignoring depth thickness ratio of web in excess of the class 3 (semicompact) limit. g d = Depth of web. t = thickness of web. e)]1/2 518 — STAAD. when transverse stiffeners are provided only at supports. w FYLD = Yield Strength of Web.35) for webs with stiffeners.Pro . w v = √ ( 250 / FYLD ) K = Shear Buckling Coefficient: = 5.35 + 4. w λw = [FYLD / (√3 · τcr. 0. λw ≤ 0. d = Clear Depth of Web between Flanges. λw ≥ 1.4.11F. Indian Codes .8 < λw < 1.Steel Design per IS 800:2007 a.4.2. with reference to Clause 8. whichever is appropriate.0 / (c/d)2 for (c/d) ≥ 1.2.0 = 5.e = The Elastic Critical Shear Stress of the Web τcr.0 + 5. t = Thickness of Web.(a) n Vn = Vcr = τb · Av A = AY or AZ.2 τ cr.8) ) · (FYLD / √3) when.1. When subjected to shear buckling: τab = 0.e = (Kv · π2 · E) / (12 · (1 – μ2 ) · (d/tw)2 ) λ = Non-dimensional Web Slenderness Ratio for Shear Buckling Stress. When subjected to pure shear: τab = 0. = 4.1. v Shear buckling must be checked when (d/ tw) > 67 · ϵw for webs without stiffener or (d/tw) > 67 · ϵw · √(Kv /5.70 · Vn · Av Where: V = Nominal Shear Strength as per Clause 8.8 = ( 1 – 0.35 / (c/d)2 for (c/d) < 1.2 = FYLD / (√3 · λw2 ) when.8 · (λw .0.40 · FYLD b.0 c = Spacing of Transverse Stiffeners μ = Poisson’s Ratio τ = Shear Stress corresponding to Web-buckling: b = FYLD / √3. when.35. 8(λw . International Design Codes Manual — 519 .4.8) ](fyw⁄√3) iii. You can control the lateral support condition of the member by the use of LAT parameter. determined as follows: b i.6 Bending The design bending moment capacity of a section is primarily dependent on whether the member is laterally supported or unsupported.8 τb = fyw⁄√3 ii.0.35 + 4.2 τb = [1 . Design methods for resistance to shear buckling are described in clause 8.e = elastic critical shear stress of the web = (kv ·π2 ·E)/[12·(1 .0 c = spacing of transverse stiffeners d = depth of the web 11F. given by: λw= [ fyw⁄(√3 τcr.2 of IS:800-2007 code. When λw ≤ 0.2.0 + 5.e )]1/2 τ cr.0. Vn = Vcr Where: V = shear force corresponding to web buckling cr = Av · τb τ = shear stress corresponding to web buckling.Slender Sections Slender sections should be verified against shear buckling resistance if d/tw > 67 · ε for web without stiffeners or if it exceeds 67 · ε · √(Kv ⁄5.8 < λw < 1.35/(c/d)2 for c/d < 1.2 τb = fyw⁄((√3 λw2 ) ) λw = non-dimensional web slenderness ratio or shear buckling stress.35) for a web with stiffeners.μ2 ) (d⁄tw)2 ] μ = Poisson’s ratio and K = v l l l 5.0 5.35 when transverse stiffeners are provided only at supports 4.2. When λw ≥ 1. When 0.0/(c/d)2 for c/d ≥ 1. 2 of IS 800:2007.60·Md /Zetz Where: M = Design Bending Strength as per Clause 8. About the major axis: fabcz = 0.60·Md /Zecz fabtz = 0.11F. respectively: fbcz = Mz/Zecz fbtz = Mz/Zetz fbcy = My /Zecy fbty = My /Zety The permissible bending stress is given as follows: a.2.60·FYLD for Semi-compact sections b. = Plastic Section Modulus of the Section.2 d Md = βb · Zpz · fbd fbd = χLT · FYLD / γmo Z Z ez pz = Elastic Section Modulus of the Section.2. about major (Z) and minor (Y) axes. based on the following factors: l Lateral Torsional Buckling Section Classification l Working Stress Design Actual bending stress values are given by.Steel Design per IS 800:2007 If the member is laterally supported. then the design strength is calculated as per the provisions of the section 8. Indian Codes . based on the following factors: l Whether section with webs susceptible to shear buckling before yielding Shear Force to Design Shear Strength Ratio Section Classification l l If the member is laterally unsupported. For laterally unsupported beams: i. 520 — STAAD.66·FYLD for Plastic or Compact sections Fabc = Fabt = 0. For laterally supported beams: Fabc = Fabt = 0.1 of IS 800:2007.2. then the design strength is calculated as per the provisions of the section 8.Pro . 0 for Plastic and Compact Section or Zez/Zpz for Semib Compact Section. International Design Codes Manual — 521 . It = Torsional constant of the section.21 for Rolled Steel Section and 0.49 for Welded Steel LT Section β = 1.α = 0.2 ) + λLT2 ) χ = The Bending Stress Reduction Factor to account for Lateral LT Torsional Buckling. G = Shear modulus of the material. About the minor axis. the permissible bending stress is calculated as for a laterally supported section. Slender Sections For member with slender section subjected to bending. χLTZ = 1 2 2 ϕ LTZ + ϕ LTZ − λ LTZ Z = Elastic Section Modulus of the section about Major Axis for ecz the compression side. ii.5 · Bf) Where: Z ez = Elastic Section modulus about major principal axis. λ LT = Non-dimensional slenderness ratio λLT = (βb · Zpz · FYLD / Mcr)1/2 ≤ (1. It = Warping constant of the section. Zez = 2·[Bf · tf3 /12 + (Bf · tf) · (D/2 . M cr = π 2EI y 2 L LT GI t + π 2EI w L LT 2 Iy = Moment of inertia about the minor axis.5 · D) Zey = 2·(Bf · tf3 /12) ⁄ (0. moment is taken by flanges alone.tf/2)2 )] ⁄ (0.2 · Zez · FYLD / Mcr )1/2 ϕLT = 0. Z = Elastic Section Modulus of the section about Major Axis for etz the tension side.5 · ( 1 + αLT · ( λLT – 0. Design bending strength should be calculated with effective elastic modulus disregarding the contribution of web of the section. L = Effective length for lateral torsional buckling as determined LT using either the KX or LX parameters. 6·Ky (Cmy fbcy /fabcy ) + Kzfbcz/fabcz ≤ 1. Indian Codes . moment.6fy ) + fbcy /fabcy + fbcz/fabcz ≤ 1.2. CMY and CMZ. Combined Axial Compression and Bending — The following formulas are intended to require member stability: fc/facy + 0.11F.3. shear. 11F. Working Stress Method The following interactions are considered: a. b. 9. The Moment Capacity will be Md = Ze· fy /γm0 for “Laterally Supported” condition. Limit State Method This interaction check is done taking care of two aspects: l Section Strength Overall Member Strength l Section Strength interaction ratio is calculated as per sec. torsion . CMX. Note: Slender section can only attain elastic moment capacity and cannot reach to plastic moment capacity. B = Width of flange.6·Ky (Cmy fbcy /fabcy ) + KLTfbcz/fabcz ≤ 1. f is defined in clause 8.1 of the code.Pro . taking care of the design parameters PSI.0 522 — STAAD. Combined Bending and Shear — No reduction in allowable stresses for the interaction of bending and shear is considered. 9.0 fc/(0. D = Overall depth of section.2 of IS:800-2007 (described in previous Working Stress bd Design section). T = thickness of flange.2.2.Steel Design per IS 800:2007 Z ey f f = Elastic Section modulus about minor principal axis.0 fc/facz + 0. The Moment Capacity will be Md = Ze· fbd /γm0 for “Laterally Un-Supported” condition.7 Combined Interaction Check Members subjected to various forces – axial.are checked against combined interaction check. Where. Overall Member Strength interaction ratio is calculated as per sec.3. at f . Double Angle. 11F. respectively.f = Allowable bending compressive stress about minor and major abcy abcz axes. governed by buckling. t f = Allowable axial tensile stress. Tee.0. These parameter names.1·ny /(CmLT . HSS Tube.0. f .8·nz KLT = 1 .f = Allowable bending tensile stress about minor and major axes. about the acy acz local Y and Z axis.Where: f = Actual axial compressive stress. For more information on these facilities.2)·nz ≤ 1 + 0.0. Channel. Ky = 1 + (λy . International Design Codes Manual — 523 .25) ≥ 0. the specified steel section available in Steel Section Library of STAAD may be used (namely: I-shaped section. Member properties may also be specified using the User Table facility except for the General and Prismatic member types.4 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.0. abty abtz respectively. refer to Section 1. with their default values. respectively.25) c.0 Where: f = Actual axial tensile stress. bcy bcz respectively.3 Member Property Specification For specification of member properties. f = Actual bending tensile stress about minor and major axes. f . f = Actual bending compressive stress about minor and major axes.0. HSS Pipe. bty btz respectively. 11F.2)·ny ≤ 1 + 0. or Double Channel section). f .1·λLT·ny /(CmLT . are listed in the following table.7 the STAAD Technical Reference Manual. Angle. f = Allowable compressive stress. Combined Axial Tension and Bending — The following formulas are intended to require member stability: ft/fat + fbty /fabty + fbtz/fabtz ≤ 1. c f .8·ny Kz = 1 + (λz . Indian Codes . end bolt line.0 (as per Section 6. This parameter is applicable only when DBS = 1.1 of the Technical Reference Manual. as per Section 6. See section 5. AVN 524 — STAAD. based on the endconnection type.0 (as per Section 6. ALPHA 0.Pro .6 = For one or two bolts 0.1).1).Steel Design per IS 800:2007 Table 11F. AVG None (Mandatory for Block Shear check) None (Mandatory for Block Shear check) Minimum Gross Area in shear along bolt line parallel to external force.4.8 = For four or more bolts ATG None (Mandatory for Block Shear check) Minimum Gross Area in Tension from the bolt hole to the toe of the angle.3.4. This parameter is applicable only when DBS = 1.0 (as per Section 6.3: 0. perpendicular to the line of the force.1).11F.8 A Factor. controlling the Rupture Strength of the Net Section. Minimum Net Area in shear along bolt line parallel to external force. This parameter is applicable only when DBS = 1.0 (as per Section 6. end bolt line. ATN None (Mandatory for Block Shear check) Minimum Net Area in Tension from the bolt hole to the toe of the angle.4.48.1).4.7 = For three bolts 0.1-Indian Steel Design IS 800:2007 Parameters Parameter Name CODE Default Value Description - Must be specified as IS800 LSD Design Code to follow. perpendicular to the line of the force. This parameter is applicable only when DBS = 1. denoting starting point for calculation of "Deflection Length". as per Section 9.9 0.3.1. section 9.0 = design at ends and those locations specified by the SECTION command.2.2.2) Cm value in local Y & Z axes.Parameter Name BEAM Default Value Description 1.0 0.0 DFF None (Mandatory for deflection check) Start Joint of member End Joint of member 1000 in. denoting end point for calculation of "Deflection Length". 0 = Minimum detail 1 = Intermediate detail level 2 = Maximum detail CAN 0. DJ1 Joint No. "Deflection Length" / Maximum allowable local deflection.2: 0 = non-cantilever beams for bending check and deflection check 1 = cantilever beam CMX 0.2.2. Check for Design against Block Shear: 0 = Design against Block Shear will not be performed 1 = Design against Block Shear will be performed If DBS = 1.0. and ATN must be supplied to calculate Block Shear Strength. Joint No. ATG.9 Equivalent uniform moment factor for Lateral Torsional Buckling(as per Table 18. AVN.0 = design at ends and at every 1/12th point along member length (default). as per section 8. Maximum allowable depth. Non-Zero Positive values of AVG. 1.0 Beam Type.3. DJ2 DMAX International Design Codes Manual — 525 . Tdb. CMY CMZ DBS 0. 8) LY Member Length Member Length 180 LZ MAIN 526 — STAAD.Steel Design per IS 800:2007 Parameter Name DMIN FU Default Value Description 0.3.Pro .2D of web from the compression flange 2 = Longitudinal stiffeners are provided at 0.2.0 LAT 0. Effective Length Factor for Lateral Torsional Buckling (as per Table-15. Section 8.1 and 8. as per Section 8. Section 8.0 KZ 1.0 LST 0 Defines the number of longitudinal stiffeners used: 0 = No longitudinal stiffener 1 = Longitudinal stiffener is provided at 0.2D and 0. Usually. Allowable Slenderness Limit for Compression Member (as per Section 3.5D of the web from the compression flange LX Member Length Effective Length for Lateral Torsional Buckling (as per Table-15.0 in. Indian Codes . Yield Strength of Steel in current units. respectively: 0 = Beam is laterally unsupported 1 = Beam is laterally supported FYLD 250 MPA KX 1.11F. 420 MPA Minimum allowable depth.3.0 KY 1.1) K value in local Y-axis. the Minor Axis. Same as above except in Z-axis (Major). Specifies lateral support of beam. Ultimate Tensile Strength of Steel in current units.1) Length to calculate Slenderness Ratio for buckling about local Y axis.2. the Major Axis. Usually.2. K value in local Z-axis. 1 of the Technical Reference Manual for details. Ratio of the Moments at the ends of the laterally unsupported length of the beam.2.1: 0.8) Used to search for the lightest section for the profile(s) specified for member selection. Allowable Slenderness Limit for Tension Member (as per Section 3.0 RATIO 1.1.Parameter Name NSF Default Value Description 1. 0 = Minimum detail 1 = Intermediate detail level 2 = Maximum detail TSP TST 0 0 Spacing of transverse stiffeners. Used to control transverse stiffeners in design: 0 = No Transverse Stiffener is provided 1 = Transverse Stiffener is provided 11F.0 = For any other case TMAIN 400 PROFILE None PSI 1.0 Net Section Factor for Tension Member. International Design Codes Manual — 527 .6.8 = where Factored Applied Moment and Tension can vary independently 1.0 Permissible ratio of the actual to allowable stresses. as per Section 9. Specifies the section type per 8. See Section 5.48.3.5 Code Checking and Member Selection Both Code Checking and Member Selection options are available for the IS 800: 2007 code.1(c): 1 = Hot rolled section 2 = Welded section STP 1 TRACK 0 Controls the levels of detail to which results are reported. 11F.6.2 Example 2 Commands for member selection UNIT NEWTON METER PARAMETER 1 CODE IS800 LSD MAIN 160 MEMB 7 KY 0.8 MEMB 2 TMAIN 350 MEMB 2 TRACK 2 MEMB 2 CHECK CODE MEMB 2 11F. Check per the IS800: 2007 y u Limit State Design methodology. Refer to Section 2.3 of the Technical Reference Manual for details the specification of the Member Selection command. bending strength.1 Example 1 Commands for code checking UNIT NEWTON METER PARAMETER 1 CODE IS800 LSD ALPHA 0.Steel Design per IS 800:2007 Refer to Section 2. and shear strength of laterally supported plate girder 800-6-200-10 given F = 250 MPa and F = 420 MPa.Pro .5. Refer to Section 5.1 Solution Material properties: 528 — STAAD.11F.5 of the Technical Reference Manual for general information on Code Checking.48. Refer to Section 5.8 MEMB 7 KZ 0.6 Verification Example Calculate compressive strength. 11F.6 of the Technical Reference Manual for general information on Member Selection.2 of the Technical Reference Manual for details the specification of the Code Checking command.5.7 ALL DBS 1 ALL CAN 1 MEMB 2 PSI 0.9 MEMB 7 FYLD 350 ALL SELECT ALL 11F. Indian Codes .48. 7 > 9.800 mm2 Izz = 912.0 b/tf = 97/10 = 9.95 mm Rzz = √(Izz⁄Area) = 321. < 13.0(10)5 MPa should be used.8 > 42·ε = 42(1. International Design Codes Manual — 529 .846 MPa Cross sectional properties: Ag = 800·6 + 2·(200·10) = 8.E = 2.0) = 42 d/tw = 800/6 = 133.1(10)6 mm4 Iyy =13.0) 1 + 2(0. Web: r2 = (Fx /Area)/fy = (19.8 Thus.0 kN·m y z M = 51. the web is considered slender.644 / 8.800)/250 = 0.2 kN y z F = 2.tw)/2 = (200 .Pro.33 > 123.0089 126ϵ 1 + 2r 2 = 126(1.659 kN·m Section Classification Flange: b = (bf .644 kN (Compression) x F = 1.0(1 + μ) = 78.95 mm Force: F = 19.35(10)6 mm4 Ryy = √(Iyy ⁄Area) = 38.0 kN M = 0.3 G = E/2.0 kN·m x M = 10.6·ε Thus. IS 800:2007 specifies that a modulus of 2. μ = 0. the flange is considered semi-compact.05(10)5 MPa Note: This is the default value of the modulus of elasticity for steel used by STAAD.0089) = 123.4·ε.6)/2 = 97 mm ε f = √(250/fy ) = √(250/250) = 1. 2) + (0.1.33(10)6 mm4 530 — STAAD.95 = 15. χ χ= χ= 1 ϕ+ ϕ −λ 2 2 ≤ 1.0 mm and buckling is f about YY axis (per Table 7 and Table 10 in IS 800:2007). Partial factor of safety γmo = 1.5[1 + 0.800 .05(10) (42.7.0(1.1 of IS 800:2007): Fcc = π E (KL / R ) 2 2 = π 2.077 kN Calculation of bending strength The web is slender and hence it is disregarded in bending strength calculation.Steel Design per IS 800:2007 The overall section is classified as slender.33 .000) / 321. mm2 Slenderness ratio: (ky L/Ry ) = 0.36) 2 2 5 = 1.49(0.95 = 42.42. Indian Codes .512.1. is equal to 0.0·ε) · tw2 = 8.1) = 195.2) + λ2 ] = 0.10 Per Cl.49 and buckling class is c as T < 40.677 − 0. 200(10) 3 I z = 2 + 200 × 10 12 ( 800 2 + 10 2 2 ) = 656.60(10)6 mm3 Iy =2(10)(200)3 ⁄12 = 13.471)2 ] = 0.0.·(195. 127 MPa Non-dimensional effective slenderness ratio: = Fy Fcc = 250 1.0·(5.677 Stress reduction factor.(d/tw .512.0.86 < 1.53 Euler buckling stress (per Cl. 127 = 0.000) / 38.471 2 2 fcd = χ·(fy /γmo ) = 0.1(10) 6 mm4 Zez = Iz/(820/2) =656.Pro . Calculation of compressive strength Net area of section: Ae= Ag .677 + 0.5[1 + α(λ .2.11F.0 1 0.7.7.42.5 MPa Design compressive strength (per Cl.1(10)6 /410 = 1. α.86·(250 / 1.2.36 (kzL/Rz) = 1.0 = 0.471 Imperfection factor.1.33·(5.[133.471 .1 of IS 800:2007: ϕ = 0.0)]·(6)2 = 5.5) = 1.2 of IS 800:2007): Pd = Ae·fcd = 5. 60(10)6 250 449.2.49 for welded steel section per Cl.333(10)3 mm4 For laterally supported beam: Mdz = Zez · Fy /γmo = 1.13 + 1.0 Hence.2 of IS 800:2007 ϕLTZ = 0.8.0 = (800 + 10)2 · 2003 · 10/24.574(250)/1.5×[1 + αLT (λLTZ .30 kN·m Calculation of shear strength c = spacing of stiffener = 1000 mm d = depth of web = 800 mm c/d = 1000/800 = 1.10 = 364 kN·m Mdy = Zey · Fy /γmo =133.0/(c/d)2 = 7.35 + 4.33(10)6 5. 333 + = 449.33(10)6 /(0.333(250)/1.943 α LT = 0.574 fbdz = (χLTZ· Fy ) ⁄ γmo = 0.5×200) = 133.47 International Design Codes Manual — 531 .8.6 kN·m MdY = (Zey · Fy ) / γmo = 133.0.25 > 1.2.1 = 30.35 = 81.333(250)/1. 846133.4 MPa Mdz = Zez· fbdz = 1.2.0] = 133.333 mm3 Ixx = 2(Bf · Tf3 /3.13 2 − 0.187(10) 12 5.187(10)12 mm6 Elastic lateral torsional buckling moment (per Cl.2.60(10)6 (250)/1.1 of IS 800:2007): LLT = 5.05(10) 513.8(10) 6 ( ) = 0.8 kN ⋅ m λLTZ = Z ezF y M cr = 1.8.4) = 208.3 kN·m For laterally unsupported beam: Warping constant: Iw = (d + Tf)2 · Bf3 · Tf/24.(a): kv = 5.1 = 30.33 67 k v / 5.0 = 2. 000 78. 000 2 π 22.4.13 χLTZ = 1 ϕ LTZ + 2 2 ϕ LTZ − λ LTZ = 1 1.943 2 = 0.05(10) 52.Zey = Iy ⁄(0.2) + λLTZ2 ] = 1.1 = 130.91 d/Tw = 800/6 = 133.5×Bf) = 13.2.0) = 2.0[(200)(10)3 /3. per Cl.6(10)6 (130.000 mm M cr = = π 2EI y L LT 2 GIxx + 2 π 2EI w L LT 2 π 22. 1 200(10)(82.0 kN 11F.776 Negligible 532 — STAAD.5 kN = 300.732 Negligible MInor Axis Shear Strength.077 1. e = k vπ E 12 1 − µ 2 d / T w 2 2 ( ) = 7.35).Steel Design per IS 800:2007 Since.323 > 1. shear strength is governed by shear buckling.e = 410 3 ⋅ 82.6 208. V (kN) crZ 300. Elastic critical stress of the web tcr.681 Negligible 30.Pro . d/Tw > 67√(kv ⁄5.6. P (kN) d Reference STAAD.44 = 1. V (kN) crY 208.0 299.Pro Difference 1.46) 1. Indian Codes .303 Negligible 359.91 ⋅π 2.2-IS 800:2007 Verification Problem 1 Item Compressive Strength.323) 2 = 82. M dz (kN·m) (Laterally unsupported) Minor Axis Bending Strength.46) 1.05(10) 2 5 2 12 1 − 0.33 ( ) = 82.11F.076(10)3 Negligible Major Axis Bending Strength.5 359.30 30.1 = 359.2 Hence τb = f yw 3λ w 2 = 250 3 (1. M dy (kN·m) (Laterally unsupported) Major Axis Shear Strength.46 Shear force corresponding to shear buckling = A · τ v b VcrY = VcrY = A WY ⋅ τ b γ m0 A WZ ⋅ τ b γ m0 = = 800(6)(82.3 2 133.2 Comparison Table 11F.44 Non-dimensional web slenderness ratio for shear buckling stress: λw = f yw 3 t cr . 2 0 5 0.3 DENSITY 76.004 END MEMBER PROPERTY AMERICAN 1 UPTABLE 1 SLEND MEMBER PROPERTY INDIAN 2 TABLE ST ISMB500 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 JOINT LOAD 3 FY -2 MEMBER LOAD International Design Codes Manual — 533 .01 0.2E-005 DAMP 0.006 0.8195 ALPHA 1.0088 0.6.90933E-007 0.3 STAAD Input File STAAD SPACE START JOB INFORMATION ENGINEER DATE 22-OCT-08 END JOB INFORMATION INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 0 0 0.2 0.000912133 1.03 END DEFINE MATERIAL START USER TABLE TABLE 1 UNIT METER KN WIDE FLANGE SLEND 0. DEFINE MATERIAL START ISOTROPIC STEEL E 2. 3 5 5 0.33477E-005 1.82 0.11F. 2 2 3.05E+008 POISSON 0.00492 0. MEMBER INCIDENCES 1 1 2. IS-800 2007 (V2.33 ALL STP 2 ALL TST 1 MEMB 1 TSP 1 MEMB 1 ***LATERALLY UNSUPPORTED**** *LAT 1 ALL TRACK 2 MEMB 1 CHECK CODE MEMB 1 PARAMETER 2 CODE IS800 LSD CAN 0 MEMB 1 KY 0.PRO CODE CHECKING .Pro .0) ************************************************ 534 — STAAD.6.33 ALL STP 2 ALL TST 1 MEMB 1 TSP 1 MEMB 1 ***LATERALLY SUPPORTED**** LAT 1 ALL TRACK 2 MEMB 1 CHECK CODE MEMB 1 FINISH 11F.4 Output TRACK 2.11F.2 2 FZ -2 SELFWEIGHT Y -1 ALL PERFORM ANALYSIS PRINT SUPPORT REACTION PRINT MEMBER FORCES PARAMETER 1 CODE IS800 LSD CAN 0 MEMB 1 KY 0.0 output for the Laterally unsupported check STAAD.Steel Design per IS 800:2007 2 UNI GY -2 JOINT LOAD 2 FX 1. Indian Codes . |---------------------------------------------------------------------------------| | Member Number: 1 | | Member Section: ST SLEND (UPT) | | Status: PASS Ratio: 0.000E+00 | | Parameters: LZ: 5.659E+00 | |---------------------------------------------------------------------------------| | Section Properties: (Unit: CM ) | | AXX: 88.000 KY: 0.580E+03 | | ZEY: 133.000E+00 | | KZ: 1.213E+03 RZZ: 32.000E+00 | | MX: 0.1.644E+00 C | |---------------------------------------------------------------------------------| | Section Class: Slender.00 | | Critical Condition: Sec.895E+00| | AZZ: 40.IS-800 2007 (V2.000E+00 IZZ: 91.200E+00 | |---------------------------------------------------------------------------------| | Slenderness Check: (Unit: METE) | | Actual Length: 5.000E+00 MY: -10.187E+06| | ZEZ: 2.000E+00 IXX: 19.401 Critical Load Case: 1 Location: 0.37 Allowable Ratio: 180.200E+00 FZ: -2. Flange Class: Semi-Compact. 9.PRO CODE CHECKING .1 | | Critical Design Forces: (Unit: KN METE) | | FX: 19.225E+03 ZPZ: 2.3.477E+00 ZPY: 207. Web Class: Slender | |---------------------------------------------------------------------------------| STAAD.644E+00 C FY: -1.0) ************************************************ |---------------------------------------------------------------------------------| International Design Codes Manual — 535 .093E+00 CW: 2.000E+00 MZ: 51.000E+00 LY: 5.195E+00| | AYY: 48.00 LOAD: 1 FX: 19.335E+03 RYY: 3.000E+00 IYY: 1.330 | | Actual Ratio: 42. 1 | | 536 — STAAD.1.000E+00| | Capacity: 299.2 | | Capacity: 1.:Cl.000E+00 General | | Major Axis: Actual Design Force: 51.:Cl. 7.000E+03 As per sec.4.1.000 ALPHA: 0.:Cl.:Cl. No. No. 8.11F.4.2 | | Actual Design Force: 19. 7.000E+03 | | NSF: 1. No.:Cl.Pro . 8.2 | | Minor Axis: Actual Design Force: -2.Steel Design per IS 800:2007 Member Number: 1 | | Member Section: ST SLEND (UPT) | |---------------------------------------------------------------------------------| | Tension: (Unit:KN METE) | | Parameters: FYLD: 250.000E+00 LC: 1 Loc: 0. No.659E+00 LC: 1 Loc: 0.2 | | Minor Axis: Actual Design Force: -10.800 DBS: 0 | | Capacity: 2. No.000E+00| | Capacity: 208.:Cl.000E+00 LC: 0 | |---------------------------------------------------------------------------------| | Compression: (Unit:KN METE) | | Buckling Class: Major: b Minor: c As per Sec.2.2 | | Actual Design Force: 0.000E+00| | Capacity: 30.:Cl.1.2. 8.200E+00 LC: 1 Loc: 0.000E+00| | Capacity: 359.303E+00 As per sec. No.732E+00 As per sec. No.776E+00 As per sec.644E+00 LC: 1 | |---------------------------------------------------------------------------------| | Shear: (Unit:KN ) | | Major Axis: Actual Design Force: -1.000E+00 LC: 1 Loc: 0. 8. 6. Indian Codes .2 | |---------------------------------------------------------------------------------| | Bending: (Unit:KN METE) | | Parameters: Laterally Unsupported KX: 1.2.000E+03 FU: 420.681E+00 As per sec.00 LX: 5.076E+03 As per sec. 3.000 0 0. No.233 1 5.000E+00 | | Sec.007 1 0.3.3.1.000E+00 | | Shear Major 0.0) ************************************************ |---------------------------------------------------------------------------------| | Member Number: 1 | | Member Section: ST SLEND (UPT) | | Status: PASS Ratio: 0.018 1 0.401 As per sec.00 | | Critical Condition: Sec.0 output for the laterally supported check STAAD.000E+00 | | Sec.000E+00 | | Bend Major 0.340 1 0. Location from Start | | | | Tension 0.210 1 5.2.1.900 | | Interaction Ratio: 0.360 Critical Load Case: 1 Location: 0. 9.000E+00 | |---------------------------------------------------------------------------------| TRACK 2.900 CMY: 0.2 (Z) 0. 9.3.PRO CODE CHECKING .000E+00 | |---------------------------------------------------------------------------------| | Checks Ratio Load Case No. 9.248 1 0.401 1 0.000E+00 | | Bend Minor 0.900 CMZ: 0. 9. 9.:Sec.00 CMX: 0.003 1 0.000E+00 | | Sec.000E+00 | | Compression 0.3.000E+00 | | Shear Minor 0.|---------------------------------------------------------------------------------| | Combined Interaction: | | Parameters: PSI: 1.1.1 0.IS-800 2007 (V2.1 | | LC: 1 Loc: 0.2 (Y) 0.1 | | Critical Design Forces: (Unit: KN METE) | International Design Codes Manual — 537 .2. 000E+00 | | MX: 0.093E+00 CW: 2.Pro .000E+00 LY: 5.330 | | Actual Ratio: 42.800 DBS: 0 | 538 — STAAD.200E+00 FZ: -2.000E+00 MZ: 51.477E+00 ZPY: 207.000E+00 IYY: 1.644E+00 C FY: -1.11F.659E+00 | |---------------------------------------------------------------------------------| | Section Properties: (Unit: CM ) | | AXX: 88.225E+03 ZPZ: 2.335E+03 RYY: 3.000E+00 IZZ: 91.00 LOAD: 1 FX: 19.000 ALPHA: 0.IS-800 2007 (V2. Web Class: Slender | |---------------------------------------------------------------------------------| STAAD.000 KY: 0.000E+00 | | KZ: 1. Indian Codes .000E+03 FU: 420.580E+03 | | ZEY: 133.187E+06| | ZEZ: 2.000E+00 | | Parameters: LZ: 5.Steel Design per IS 800:2007 | FX: 19.PRO CODE CHECKING .195E+00| | AYY: 48.000E+00 MY: -10. Flange Class: Semi-Compact.213E+03 RZZ: 32.644E+00 C | |---------------------------------------------------------------------------------| | Section Class: Slender.000E+03 | | NSF: 1.000E+00 IXX: 19.200E+00 | |---------------------------------------------------------------------------------| | Slenderness Check: (Unit: METE) | | Actual Length: 5.37 Allowable Ratio: 180.0) ************************************************ |---------------------------------------------------------------------------------| | Member Number: 1 | | Member Section: ST SLEND (UPT) | |---------------------------------------------------------------------------------| | Tension: (Unit:KN METE) | | Parameters: FYLD: 250.895E+00| | AZZ: 40. 000E+00| | Capacity: 363. No.1. No.900 | | Interaction Ratio: 0.076E+03 As per sec. Location from Start | | Capacity: International Design Codes Manual — 539 .644E+00 LC: 1 | |---------------------------------------------------------------------------------| | Shear: (Unit:KN ) | | Major Axis: Actual Design Force: -1.000E+00 LC: 0 | |---------------------------------------------------------------------------------| | Compression: (Unit:KN METE) | | Buckling Class: Major: b Minor: c As per Sec.2 | | Capacity: 1. No.776E+00 As per sec.2 | | Actual Design Force: 0.4.3.:Cl.1.360 As per sec.:Sec.2 | |---------------------------------------------------------------------------------| | Bending: (Unit:KN METE) | | Parameters: Laterally Supported KX: 1.2. 8.2. No.2 | | Actual Design Force: 19. No. 6.00 CMX: 0.000E+03 As per sec.000E+00 LC: 1 Loc: 0.1 | |---------------------------------------------------------------------------------| | Combined Interaction: | | Parameters: PSI: 1. 7.1 | | Minor Axis: Actual Design Force: -10. 7.659E+00 LC: 1 Loc: 0. 9.4.710E+00 As per sec.:Cl.:Cl.1 | | LC: 1 Loc: 0. No.1.732E+00 As per sec.000E+00| | Capacity: 299.:Cl.303E+00 As per sec.1.900 CMZ: 0. 8. 8.1.2. 8. No.:Cl.:Cl. No.:Cl.2 | | Minor Axis: Actual Design Force: -2.000E+00| | Capacity: 30.000E+00| | Capacity: 359.000E+00 | |---------------------------------------------------------------------------------| | Checks Ratio Load Case No.200E+00 LC: 1 Loc: 0.000E+00 LC: 1 Loc: 0.000E+00 General | | Major Axis: Actual Design Force: 51.00 LX: 5.2.900 CMY: 0. 000E+00 | | Shear Minor 0.007 1 0.000 0 0. 9.2 (Y) 0.1.2. 9.Steel Design per IS 800:2007 | | | Tension 0.3.3.003 1 0. 9.000E+00 | | Shear Major 0.018 1 0.000E+00 | | Sec.141 1 5.11F.000E+00 | |---------------------------------------------------------------------------------| 540 — STAAD.000E+00 | | Sec.000E+00 | | Sec.000E+00 | | Bend Major 0.2 (Z) 0.360 1 0.126 1 5.340 1 0. Indian Codes .Pro .142 1 0.3.2.1 0.000E+00 | | Compression 0.000E+00 | | Bend Minor 0. Section 12 Japanese Codes International Design Codes Manual — 541 . 542 — STAAD.Pro . 2 Member Dimensions Concrete members which will be designed by the program must have certain section properties input under the MEMBER PROPERTY command. Warning: It is absolutely imperative that you do not provide the cross section area (AX) as an input. will be assumed to be circular with a 350 mm diameter. 12A. the details regarding placement of the reinforcement on the cross section are also reported in the output. and Circular) l 12A. In addition. 12A. Slenderness effects result in additional forces being exerted on the column over and above those obtained from the elastic analysis. There are two options by which the slenderness effects can be accommodated.3 Slenderness Effects and Analysis Considerations Slenderness effects are extremely important in designing compression members. Design of members per AIJ requires the STAAD Japan Design Codes SELECT Code Pack.1 Section Types for Concrete Design The following types of cross sections for concrete members can be designed: l For Beams — Prismatic (Rectangular and Square) For Columns — Prismatic (Rectangular. Design for a member involves calculation of the amount of reinforcement required for the member. the first set of members are rectangular (450 mm depth and 250 mm width) and the second set of members. with only depth and no width provided. The following is an example the required input: UNIT MM MEMBER PROPERTY 1 3 TO 7 9 PRISM YD 450. Square.Pro is capable of performing concrete design based on the Japan code AIJ 2002 Architectural Institute of Japan Standards for Structural Calculation of Steel Reinforced Concrete Structures. ZD 250.12A. In the above input. Japanese Codes .Concrete Design Per 1991 AIJ STAAD. Calculations are based on the user specified properties and the member forces obtained from the analysis. These are the D (YD) and b (ZD) dimensions for rectangular or square cross sections and the D (YD) for circular cross sections. 11 13 PR YD 350. International Design Codes Manual — 543 . The results include design results for most critical load case. STAAD does not factor the loads automatically. Example UNIT KG CM START CONCRETE DESIGN CODE JAPAN FYMAIN SRR295 ALL FYSEC SRR295 ALL FC 350 ALL CLEAR 2. All these sections are designed for flexure. Program first try to design the section for g = 0 and pt = 544 — STAAD.Concrete Design Per 1991 AIJ The first option is to compute the secondary moments through an exact analysis. It is assumed that the magnified moment is equivalent to the total moment comprised of the sum of primary and secondary moments. The column is designed for the axial load and total of primary and secondary biaxial moments if the first method is used and for the axial load and magnified biaxial moments if the second method is used. shear and torsion for all load cases. STAAD provides facilities to design according to both of the above methods. the command PDELTA ANALYSIS must be used instead of PERFORM ANALYSIS in the input file.5 MEM 2 TO 6 TRACK 1. Secondary moments are caused by the interaction of the axial loads and the relative end displacements of a member. However this number can be redefined by NSECTION parameter. To utilize the first method.5 for dead load etc. shear and torsion.1 Design for Flexure Reinforcement for positive and negative moments are calculated on the basis of section properties provided by the user.4 Beam Design Beams are designed for flexure.12A. This is due to the fact that load combinations are just algebraic combinations of forces and moments.) should be provided by the user. The user must note that to take advantage of this analysis. The program considers 12 equally spaced divisions of the beam member.1). The second method mentioned above is utilized by providing the magnification factor as a concrete design parameter (See the parameter MMAG in Table 10A. whereas a primary load case is revised during the P-delta analysis based on the deflections. The axial loads and joint displacements are first determined from an elastic stiffness analysis and the secondary moments are then evaluated. The second option is to approximately magnify the moments from the elastic analysis and design the column for the magnified moment. Japanese Codes . Also. note that the proper factored loads (like 1.4.0 MEMB 2 TO 9 DESIGN BEAM 2 TO 9 END CONCRETE DESIGN 12A. 12A. all the combinations of loading must be provided as primary load cases and not as load combinations.Pro . It arranges the bar in layers as per the requirements and recalculate the effective depth and redesign the sections for this effective depth.0 is lower than the actual moment the program gives message that the section fails. Beams are designed for MZ only. the program will design the assigned beam(s) for torsion. cm 12A.balanced reinforcement ratio. If allowable moment is lower than the actual moment program increases g value for same pt and checks the satisfactory conditions.3 Design for Torsion Torsion design for beam is optional. This procedure continues until pt reaches to its maximum value( 2 % ). 12A. f . Q . Stirrups are always assumed to be 2-legged b.5 times the actual value and this can be done utilizing the Design Shear Modification factor. k (SMAG parameter) without changing the Design Moment. But if the allowable moment for pt = maximum value and g = 1. The program then calculates the required bar size. The reinforcement ratio for the stirrup. and spacing of stirrups. Notes: a.4. of bars needed to design the section. Notes: a. The moment MY is not considered in flexure design b. STAAD beam design procedure is based on the local practice and considering the fact that Japan is a high seismic zone area.0. If additional reinforcement is needed.0. is evaluated for the beam. MMAG parameter can be used to increase design moment c. Governing density to determine Light weight or Normal Weight Concrete is 2. If conditions are not satisfied this procedure continues until g reaches to 1. If the TORSION parameter value is 1. this additional pt is added to flexure pt and additional Pw is added to shear design Pw. The allowable shear stress of concrete. d.3 kg/sq. The program first checks whether extra reinforcement is needed for torsion or not. is added to the clear cover to take stirrup size into consideration for flexure design. aw. International Design Codes Manual — 545 . is s automatically calculated from design load type (permanent or temporary) and given density of concrete. For seismic loading it is needed to increase shear force ≥ 1. The update effective depth is used to D then calculate the allowable shear stress. is calculated for design Bar size and stirrup pitch and w all the necessary checking is done.2 Design for Shear The Design Shear value.4 cm.4.0 and then pt value is increased keeping g = 1. p . 1. This program automatically calculates the Bar size and no. the column moments will be multiplied by that value. a = 1. If the interaction equation is not satisfied program increases Pt and calculates Pcap. column shear force will be multiplied by that value.12A. MY moment. If biaxial design is requested program solve the following interaction equation 6. If the column is in "zone B" or in "zone C". while for circular sections Pg value is calculated for MZ and MY separately.0+1. maximum MZ. Column design is done for Rectangular. the program will design the column for biaxial moments. Japanese Codes . Mycap. maximum axial force. design is performed by increasing Pt and checking allowable load for that known Pt and known actual eccentricity of the column. Square and Circular sections. Otherwise column design is always uniaxial. If the BIAXIAL parameter value is 1. 8. The value of Pt needed for minimum axial force.0. program increases Pt and this procedure continues until the column design conditions are satisfied or the column fails as the required Pt is higher than Pt maximum value.0 £ a £ 2. Steps involved: 1. If the interaction equation is satisfied program determines bar size and calculates no. design is done by considering allowable tensile stress of steel only. If the SMAG parameter is used. xn is calculated for given P and Pt and checking is done for allowable moment.Concrete Design Per 1991 AIJ 12A.0 . 2. Mycap and Mzcap and solve the interaction equation again and this process continues until the eqn. 5. is satisfied or the column fails as Pt exceeds its maximum limit.66666666 ´ (ratio-0. where.Pro . But if Track 2 is used. you can get detailed design results of that member. Depending on the axial force zone is determined for Pt = 0. MZ moment. If biaxial design is not requested program assumes that interaction equation is satisfied (if uniaxial design is performed successfully). 546 — STAAD. Mzcap & Pcap represents section capacity 7. 9. and shear force. of bars and details output is written. 3. If the MMAG parameter is used.2). Both the ends of the members are designed for all the load cases and the loading which produces largest amount of reinforcement is called as critical load.0. If Track 0 or Track 1 is used. maximum MY among all the load cases for both the ends will be printed. design results will be printed for critical load only. if allowable moment is less than the actual moment. For rectangular and square sections Pt value is calculated separately for MZ and MY.5 Column Design Columns are designed for axial force. If the column is in "zone A". 4. ratio = P/Pcap & 1. Column design for biaxial moments is optional. If the column is in tension. 4. MINMAIN — Minimum required size of longitudinal/transverse reinforcing bar The other parameters shown in Table 12A. 12A. CLEAR — Distance from the outer surface of the element to the edge of the bar. it must first be modeled using finite elements and analyzed. Elements are designed for the moments Mx and My. It is necessary to declare length and force units as centimeters and Kilograms before performing the concrete design. its value stays at that specified number until it is specified again. FC— Concrete grade 3.6 Slab/Wall Design To design a slab or a wall.7 Design Parameters The program contains a number of parameters which are needed to perform the design.1 contains a complete list of the available parameters and their default values. 2. Note: Once a parameter is specified. These moments are obtained from the element force output (see Chapter 2 of the Technical Reference Manual). International Design Codes Manual — 547 .5 MEMB 2 TO 6 DESIGN COLUMN 2 TO 6 END CONCRETE DESIGN 12A. This is considered the same on both top and bottom surfaces of the element. This is the way STAAD works for all codes.12A.5. The longitudinal bar is the layer closest to the exterior face of the slab or wall. The command specifications are in accordance with Chapter 2 and Chapter 6 of the Technical Reference Manual. FYMAIN — Yield stress for reinforcing steel .transverse and longitudinal.1 are not applicable to slab or wall design. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements. The following parameters are those applicable to slab and wall design: 1.1 Example UNIT KGS CMS START CONCRETE DESIGN CODE JAPAN FYMAIN SRR295 ALL FC 210 ALL CLEAR 2. The reinforcement required to resist the Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist the My moment is denoted as transverse reinforcement. These values may be changed to suit the particular design being performed. Table 10A. 0 MAXMAIN 41. Same as FYMAIN except this is for secondary steel.2 of the Technical Reference Manual. uniaxial design only 1. Temporary Loading EFACE 0. See section 5. Permanent Loading 1. Acceptable values for steel grade and their associated yield stress values are shown in the following table.0 cm (beam) 4. Compressive Strength of Concrete. (Note: Both SFACE & EFACE are input as positive numbers).52. Design Code to follow. Program automatically calculates yield stress value depending on design load type (permanent or temporary).12A.0 Value to define biaxial or uniaxial design type for Column 0. DEPTH YD Depth of concrete member.Pro . BIAXIAL 0.0 cm Maximum main reinforcement bar size 548 — STAAD. Steel grade. Value to define design load type 0.0 cm (Column) Clear cover for Beam or clear side cover for column. Japanese Codes .1-Japanese Concrete Design Parameters Parameter Name CODE Default Value Description - Must be specified as JAPAN. design for biaxial moments CLEAR 3.Concrete Design Per 1991 AIJ Table 12A.0 FC FYMAIN 210 Kg/cm2 SR235 FYSEC SR235 LONG 0. This value defaults to YD as provided under MEMBER PROPERTIES. Face of support location at end of beam. 0 will mean spiral.0 TRACK 0. Design shear magnification factor Value to request for torsion design for beam 0.0 Beam Design: 0. maximum MZ and maximum MY among all load cases for both ends. Design results for minimum P. maximum P.0 SFACE 0.0 0.0 SMAG TORSION 1. Five section design results & design forces. Design moment magnification factor Number of equally-spaced sections to be considered in finding critical moments for beam design. torsion design needed MINMAIN 10 mm MINSEC 10 mm MMAG NSECTION 1. 2. Critical section design results. Minimum main reinforcement bar size.Parameter Name MAXSEC Default Value Description 41. Tied Column. International Design Codes Manual — 549 . Minimum secondary reinforcement bar size.0 cm Maximum secondary reinforcement bar size.0 12 REINF 0. A value of 1. 12 section design results & design forces. 2. Column Design: 1. 1. torsion design not needed 1. Detail design results for critical load case only. Face of support location at start of beam. Table 12A.Pro .12A.Concrete Design Per 1991 AIJ Parameter Name WIDTH Default Value Description ZD Width of concrete member. This value defaults to ZD as provided under MEMBER PROPERTIES.2-Table of permissible Steel Grades and associated Yield Stresses for FYMAIN and FYSEC parameters Steel Grade Long Term Loading Tension & Compression 1600 Shear Reinforcement 1600 Short Term Loading Tension & Compression 2400 Shear Reinforcement 2400 SR235 SRR235 SDR235 SR295 SRR295 SD295A SD295B SDR295 SDR345 SD345 SD390 1600 2000 3000 3000 2000 2000 3000 3000 2200 (2000) 2000 3500 3500 2200 (2000) 2000 4000 4000 550 — STAAD. Japanese Codes . can be used as member property and STAAD will automatically adopt International Design Codes Manual — 551 . The design philosophy and procedural logistics are based on the principles of elastic analysis and allowable stress design. Members are proportioned to resist the design loads without exceedance of the allowable stresses or capacities and the most economical section is selected on the basis of the least weight criteria.2 Member Capacities Member design and code checking per AIJ 2005 are based upon the allowable stress design method. 12B. I-Shape. l l The method for calculating allowable bending stress was updated for the AIJ 2005 from the AIJ 2002 code. Specify the design parameter values if different from the default values. analysis and design methods. The code checking part of the program also checks the slenderness requirements and the stability criteria. Refer to the AIJ 2002 documentation for additional details.Pro is capable of performing steel design based on the Japanese code AIJ 2005 Specifications for structural steel design. PIPE.1 General This section presents some general statements regarding the implementation of the “Architectural Institute of Japan” (AIJ) specifications for structural steel design (2005 edition) in STAAD. L-Shapes. Two major failure modes are recognized: failure by overstressing and failure by stability considerations. It is a method for proportioning structural members using design loads and forces. allowable stresses. Design of members per AIJ 2005 requires the STAAD Japan Design Codes SELECT Code Pack. Specify whether to perform code checking or member selection. 12B. and design limitations for the appropriate material under service conditions. 12B. Facilities are available for member selection as well as code checking. CHANNEL.2. Users are recommended to adopt the following steps in performing the steel design: l Specify the geometry and loads and perform the analysis. The following sections describe the salient features of the design approach.12B.Steel Design Per 2005 AIJ STAAD. Prismatic section etc. TUBE. All other allowable limit states. The basic measure of member capacities are the allowable stresses on the member under various conditions of applied loading such as allowable tensile stress. remain unchanged.1 Design Capabilities All types of available shapes like H-Shape. etc. unsupported width to thickness ratios and so on. Explained here is the procedure adopted in STAAD for calculating such capacities. These depend on several factors such as cross sectional properties. Japanese Codes .. slenderness factors. allowable compressive stress etc. 5 (For Permanent Case) = F ( For Temporary Case ) Allowable compressive stress (fc) = {1 .77 x F/ ( = f x 1.2. Calculation of sectional properties The program extract sectional properties like sectional area ( A ). program calculates moment of inertia ( I )and sectional area ( A ) for 1/6th i i section and then uses following formula: i = √(Ii/Ai) Note: The above mentioned procedure for calculation of i is applicable for I shape. I ) from in-built Japanese Steel Table and calculates Z . Moment of Inertia about Y axis and Z axis ( I . For calculation of i ( radius of gyration needed for y y z bending ).5 (for Temporary case) c Where: Δ = √(π2 E/(.Pro . Japanese Codes . STAAD compares the actual stresses with the allowable stresses as required by AIJ specifications.. T NSF = Net Section Factor for tension Actual compressive stress ( F ) = Force / A C Allowable tensile stress ( f ) t = F / 1. Axial Stress: Actual tensile stresses ( F ) = Force / ( A x NSF ). 1. 2. yy zz z Z .12B. Calculation of actual and allowable stresses Program calculates actual and allowable stresses by following methods: i. 12B.4x(λ/Δ 2 )} x F/v when λ ≤ Δ = 2. H shape and Channel sections.6 x F)) Δ=F v = 3/2 + 2/3x(λ/Δ 2 ) 552 — STAAD.Steel Design Per 2005 AIJ the design procedure for that particular shape if Steel Design is requested.2 Methodology For steel design. The design procedure consist of following three steps. i . i using appropriate formula. STEEL TABLE available within STAAD or UPTABLE facility can be used for member property. Z are section modulus for tension tz Allowable bending stress for M (fbcy ) = ft Allowable bending stress for M When λb ≤ p λb .ii.75 .5 x (f bcz for Permanent case) C = 1. fb = λb −p λ b F 1 − 0. f Where: = 1.05 (M2 / M1) + 0. fb = F/ν When p λb < λb ≤ eλb .1. f Allowable bending stress for M . fb = 1 λ 2 b F 2.Z cz are section modulus for compression Z . Bending Stress: Actual bending stress for My for compression: ( Fbcy ) = My / Zcy Actual bending stress for Mz for compression ( Fbcz) = Mz / Zcz Actual bending stress for My for tension ( Fbty ) = My / Zty Actual bending stress for Mz for tension ( Fbtz ) = Mz / Ztz Where: Z cy ty .4 λb −p λ e b ν y z When eλb < λb .3 (M2 / M1)2 Allowable bending stress for M .6 bcz For Temporary case. f y bty z btz =f =f t bcz International Design Codes Manual — 553 .17 Where: λb = My / Me e λb = 1 / 0. fs = Fs / 1. Fs = F / √(3) 3.Steel Design Per 2005 AIJ Note: The parameter CB can be used to specify a value for C directly. axial compression. Axial compressive stress ratio = FC / fc iii. Shear Stress Actual shear stresses are calculated by the following formula: qy = Qy / Aww Where: A ww = web shear area = product of depth and web thickness qz = Qz / Aff Where: A = flange shear area = 2/3 times total flange area ff Allowable shear stress.12B. For all the conditions calculated value should not be more than the value of RATIO. Japanese Codes . Shear stress ratio for qy = qy / fs viii. Conditions: i. Axial tensile stress ratio = FT / ft ii. Checking design requirements: User provided RATIO value (default 1.3 Design Parameters You are allowed complete control over the design process through the use of parameters mentioned in Table 10B. These parameters communicate design decisions 554 — STAAD. and shear) are calculated as for AIJ 2002. Combined compression & bending ratio = (Fbtz+Fbty -FC) / ft v.5.Pro . iii. See "Member Capacities" on page 570 12B. Combined tension & bending ratio = (FT+Fbtz+Fbty ) / ft vi.0) is used for checking design requirements: The following conditions are checked to meet the AIJ specifications. If for any condition value exceeds RATIO. program gives the message that the section fails.3 of this chapter. von Mises stress ratio (if the von Mises stresses were set to be checked) = fm/(k ft) Note: All other member capacities (axial tension. Shear stress ratio for qz = qz / fs ix. Combined tension & bending ratio = Fbcz/fbcz+Fbcy /fbcy .FT/ft vii. Combined compression & bending ratio = FC / fc+Fbcz/fbcz+Fbcy /fbcy iv. Depending on the particular design requirements of the situation. Table 12B. Use 0.0 0.from the engineer to the program. See "Member Capacities" on page 570 Bending Stress for how C is calculated and applied.0 = calculate moments at twelfth points along the beam. Note: Once a parameter is specified. BEAM 0. CB 0 C value from the AIJ code. some or all of these parameter values may have to be changed to exactly model the physical structure. Any other value be used in lieu of the program calculated value. 1. its value stays at that specified number until it is specified again. and use the maximum Mz location for design. denoting starting point for calculation of "Deflection Length" (See Note a) International Design Codes Manual — 555 . This is the way STAAD works for all codes.1-Japanese Steel Design Parameters Parameter Name CODE Default Value Description - Must be specified as JAPANESE 2005 to invoke the AIJ 2005. Design Code to follow. DFF None (Mandatory for deflection check) Start Joint of member "Deflection Length" / Maxm.48.0 = design only for end moments or those at locations specified by the SECTION command. See section 5. allowable local deflection DJ1 Joint No. The default parameter values have been selected such that they are frequently used numbers for conventional design.0 to direct the program to calculated Cb.1 of the Technical Reference Manual. 0 = Sidesway in local y-axis.0 KZ 1. Permissible ratio of the actual to allowable stresses. Minimum allowable depth for member.0 Same as above except in local z-axis.12B. K value in local y-axis. 556 — STAAD. Usually. denoting end point for calculation of "Deflection Length" (See Note a) Maximum allowable depth for member.0 LY Member Length Member Length 0.Pro . Usually.0 cm FYLD KY 235 MPA 1.0 LZ MAIN 0.0 = check for slenderness 1.0 = No sidesway RATIO 1. 1. 1 = Perform Von Mises stress check.Steel Design Per 2005 AIJ Parameter Name DJ2 Default Value Description End Joint of member Joint No.0 SSZ 0. Japanese Codes .0 = suppress slenderness check MISES 0 Option to include check for von Mises stresses 0 = Do not include check. Same as above except in z-axis DMAX 100 cm DMIN 0. NSF 1. this is the major axis.0 SSY 0. this is the minor axis. 0. Yield strength of steel in Megapascal. Length in local y-axis to calculate slenderness ratio. K value in local z-axis.0 Net section factor for tension members. = Perform and print deflection check. = Print all critical member stresses 2. = Print expanded output 3. However.1 Notes a. 4. For example.0 = suppress slenderness check . It may be noted that for most cases the "Deflection Length" will be equal to the length of the member.Parameter Name TMAIN Default Value Description 400 Allowable Slenderness Limit for Tension Member 1. Any value greater than 1 = Allowable KL/r in tension. Note: Only produces results when BEAM 0 is used. The parameters DJ1 and DJ2 should be used to International Design Codes Manual — 557 . A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. = Suppress critical member stresses 1. TMP 0 0 = Permanent Loading 1 = Temporary Loading TRACK 0. UNL Member Length 12B. Unsupported length for calculating allowable bending stress. "Deflection Length" is defined as the length that is used for calculation of local deflections within a member. The “Deflection Length” for all three members will be equal to the total length of the beam in this case.3. the "Deflection Length" may be different. refer to the figure below where a beam has been modeled using four joints and three members.0 Same as above provided as a fraction of actual member length. in some situations. UNF 1.0 Level of output detail: 0. = Print maximum details. These checks are performed at locations indicated by the BEAM parameter.Steel Design Per 2005 AIJ model this situation. DJ1 should be 1 and DJ2 should be 4. The default is set that this check is not performed. which is modified for beam elements based on the corresponding equation in AIJ steel design code (both 2002 and 2005 editions of AIJ).Pro V8i (SELECTseries 2) build 2007. The MISES parameter must be set to 1 to initiate the checks. indicates that the left-hand side in the equation should be less than unity. The von Misers stresses are evaluated and checked as follows: σx + 3τ xy f 2 2 < 1. The von Mises stress equation shown below.12B.07 or higher. If DJ1 and DJ2 are not used. 2. and 3.Pro . the unity check value can be modified by use of the RATIO parameter. ALL DJ1 1 ALL DJ2 4 ALL b. "Deflection Length" will default to the member length and local deflections will be measured from original member line.0 Where: Longitudinal stress in beam element: σx = Fx Ax + My Zy + Mz Zz F = Axial force x M = Bending moment about y-axis y 558 — STAAD. Thus. Japanese Codes .4 Von Mises Stresses Check Note: This feature requires STAAD. PARAMETERS DFF 300. c. D = Maximum local deflection for members 1. for all three members here. 12B. The above parameters may be used in conjunction with other available parameters for steel design. Note: As with other design checks. Along with slenderness ratios. Axial tension of 10 kN is also applied to the member. Problem A cantilever beam of length 2 meter is subjected to a permanent joint load of 3 kN in the Y direction and 2 kN in the Z direction as well as a 0. Static analysis. 12B. stresses. Given Section properties International Design Codes Manual — 559 . von Mises stress equation is checked. 3D beam element. 12B. When its left-hand side yields the maximum ratio value.5.M = Bending moment about z-axis z A = Cross-sectional area. stress value of (numerator of the von Mises stress equation) is output as the value of fm. x Z = Section modulus about y-axis y z Z = Section modulus about z-axis τxy = Mx Zx + Fy Ay 2 + Fz Az 2 M = Torsional moment x F = shear stress in y direction y z F = shear stress in z direction Z = Torsional section modulus = 2I /D x x x D = Depth of the member x I = Torsional constant x A = Effective shear area in the y direction y z A = Effective shear area in the z direction f = Allowable tensile stress t In the STRESSES output category. An H100x50x5 section is used from the Japanese steel tables. it is printed as RATIO and “VON MISES” is printed as CRITICAL COND.5 Verification Problems In the next few pages are included verification examples for reference purposes.1 Verification Problem No. 1 A slender. cantilever beam subjected to a load at the end.008 kN·m torque applied at the end. and deflections. 5 = 300.282 ) = 33.Pro . 000 37.26 N / mm 2 Since ft = FYLD/1.26/(200. So OK.0 · 1) = 0. 185 + −900.731 < 1.0 kN (Shear-Y) 2.06 = 133. A = 467 mm 2 x y z Z = 2I /D = 2·15000/100 = 300 mm 3. σ and τ x xy at the section of the fixed end are calculated as follows: + 600.000 mm 4 x A = 1185 mm 2.67 + √(62 + 4.04)2 = 146.04 x N/mm2 xy m From σ and τ . 000 1. Section forces at the fixed end are ass follow: 10.35 + 24. Z = 37400 mm 3 x x x y z The maximum of the left hand side of the von Mises stress equation apparently occurs at the fixed end of the beam.6 MPa Solution From these section forces. Japanese Codes .0 N/mm2 and k = 1 for permanent loading. 000 300 + −3.Steel Design Per 2005 AIJ D = 100 mm x I = 15. 920 σx = Fx Ax + My Zy + Mz Zz = −10.0 MPa/15 = 200. f is calculated: 2 fm = σx2 + 3τxy = (133.44 + 101.05E+05 MPa G = E/2. A = 500 mm 2. 000 2 500 + −2. 000 5.85)2 + 3(33. Unbraced length = 100mm.008 kN·m (Torsion Member Length L = 2 m.0 kN·m (Bending-Y) 6.0 kN (Shear-Z) -0. 000 2 467 = 26. Material FYLD = 300 MPa E = 2. 400 = 8.0 kN (Tension) 6.12B. Z = 5920 mm 3.0 kN·m (Bending-Z) 3.85 N/mm2 τxy = Mx Zx + Fy Ay 2 + Fz Az 2 = −8. 560 — STAAD. Ratio = 146. 2-Comparison of results for a AIJ 2005 verification problem Hand Calculation von Mises Stress.Comparison Table 12B.Pro Result 146.2E-005 DAMP 0.05E+008 POISSON 0.03 END DEFINE MATERIAL MEMBER PROPERTY JAPANESE 1 TABLE ST H100X50X5 UNIT MMS KN CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED UNIT METER KN LOAD 1 LC1 JOINT LOAD International Design Codes Manual — 561 .26 None STAAD Input File STAAD SPACE VERIFICATION EXAMPLE NO.3 DENSITY 76. 2 300 0 0 MEMBER INCIDENCES 1 1 2 UNIT METER KN DEFINE MATERIAL START ISOTROPIC STEEL E 2.8195 ALPHA 1. f (N/mm 2) m STAAD.3 Comments 146.1 START JOB INFORMATION ENGINEER DATE 18-AUG-10 END JOB INFORMATION * VERIFICATION FOR VON MISES STRESSES IN AIJ 2005 UNIT MMS KN JOINT COORDINATES 1 0 0 0. 90(KN-MET) | |PARAMETER |L1 STRESSES | |IN N MM | L1 L1 IN N MM| |--------------.Pro .( AIJ 2005) ******************************************** |--------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN CM UNIT | | * |=============================| ===|=== -----------.00 | |DESIGN CODE * | | | AZ = 4.67 | | AIJ-2005 * =============================== ===|=== ZY = 5.05 FV = 115.30 | | 0.0 output portion is as follows: STAAD.75 + FTZ = 200.4 | | DFF = 0.0 | | CB = 1.40 | | * |<---LENGTH (ME= 0.PRO CODE CHECKING .4 | | UNL = 2.92 | | * ZZ = 37.0 | L0 fbz = 24.12 | |************* iZ = 3. Japanese Codes .85 | L1 L1 FCY = 200.97 | | ZX = 0.85 + L1 L1 FTY = 200.85 | | * | ST H100X50X5 | | --Z AY = 5.5 | | dff = 0.0 | | FYLD = 300.0 | | CMZ = 0.6 + L1 fa = 8.8 | L1 FA = 189.5 | L1 L1 FCZ = 200.5 | | KL/R-Z= 7.12B.0 ABSOLUTE MZ ENVELOPE fv = 6.0 | 562 — STAAD.30 --->| iY = 1.Steel Design Per 2005 AIJ 2 FX 10 FY 3 FZ 2 MX 0.0 | | CMY = 0.0 | | (WITH LOAD NO.002 ALL MISES 1 ALL TRACK 2 ALL FYLD 300000 ALL CHECK CODE ALL FINISH Output The TRACK 2.00 +---+---+---+---+---+---+---+---+---+---| fby = 101.| |MEMBER 1 * | JAPANESE SECTIONS | | AX = 11.1 | | NSF = 1.0 -0.+ L1 L1 -------------| | KL/R-Y= 26.) FT = 200.008 PERFORM ANALYSIS LOAD LIST 1 PRINT MEMBER FORCES LIST 1 PARAMETER 1 CODE JAPANESE 2005 TMP 0 ALL UNL 0. 60 0.00 0.| fm = 146.9 | | ------------------------Tou = 34.000 | | LOADING 1 1 1 1 1 | | | |**************************************************************************| |* *| |* DESIGN SUMMARY (KN-MET) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS VON MISES 0.90 | | LOCATION 0.00 2.000 0.90 0.000 0.0 | | | | AXIAL SHEAR-Y SHEAR-Z MOMENT-Y MOMENT-Z | | | | VALUE -10.3 | | MAX FORCE/ MOMENT SUMMARY (KN-MET) Sx = 133.731 1 | | 10.000 0.000 | |* *| |**************************************************************************| | | |--------------------------------------------------------------------------| International Design Codes Manual — 563 .00 3.000 0.60 -0.00 T 0. 564 — STAAD.Pro . 12C. the steel section library available in STAAD may be used. Facilities are available for member selection as well as code checking.2 Analysis Methodology Elastic analysis method is used to obtain the forces and moments for design. 12C. The user is allowed complete flexibility in providing loading specifications and in using appropriate load factors to create necessary loading situations. Specify whether to perform code checking or member selection.12C. Analysis is done for the primary and combination loading conditions provided by the user. Japanese Codes .Pro is capable of performing steel design based on the Japanese code AIJ 2002 Specifications for structural steel design.7 the STAAD Technical Reference Manual. These properties are stored in a database file.Steel Design Per 2002 AIJ STAAD. Two major failure modes are recognized: failure by overstressing and failure by stability considerations. If International Design Codes Manual — 565 . Dynamic analysis may also be performed and the results combined with static analysis results.3 Member Property Specifications For specification of member properties of standard Japanese steel shapes. Members are proportioned to resist the design loads without exceedance of the allowable stresses or capacities and the most economical section is selected on the basis of the least weight criteria. 12C. The next section describes the syntax of commands used to assign properties from the built-in steel table. Specify the design parameter values if different from the default values. The code checking part of the program also checks the slenderness requirements and the stability criteria.1 General The design philosophy and procedural logistics are based on the principles of elastic analysis and allowable stress design. Users are recommended to adopt the following steps in performing the steel design: l Specify the geometry and loads and perform the analysis. Members properties may also be specified using the User Table facility. Design of members per AIJ 2002 requires the STAAD Japan Design Codes SELECT Code Pack.4 Built-in Japanese Steel Section Library The following information is provided for use when the built-in steel tables are to be referenced for member property specification. refer to Section 1. The following sections describe the salient features of the design approach. For more information on these facilities. l l 12C. Depending upon the analysis requirements. regular stiffness analysis or P-Delta analysis may be specified. Pro . 1 TO 9 TA ST I300X150X11 12 TO 15 TA ST I350X150X9 12C. A complete listing of the sections available in the built-in steel section library may be obtained using the tools of the graphical user interface.4. these properties are also used for member design. shear deformation is always considered for these members during the analysis. Following are the descriptions of different types of sections. the portion after the decimal point should be excluded.12C. Since the shear areas are built into these tables. 12C. Japanese Codes . An example of member property specification in an input file is provided at the end of this section.1 I shapes I shapes are specified in the following way: Note: While specifying the web thickness.4. the portion after the decimal point should be excluded.2 H shapes H shapes are specified as follows: Note: While specifying the web thickness. 1 TO 8 TA ST H200X100X4 13 TO 17 TA ST H350X350X12 566 — STAAD.Steel Design Per 2002 AIJ called for. 25 TO 34 TA ST C125X65X6 46 TO 49 TA ST C200X90X8 12C.4.4.4. the portion after the decimal point should be excluded.3 T shapes T shapes are specified as follows: Note: While specifying the web thickness. 17 TO 27 TA D C300X90X10 45 TO 76 TA D C250X90X11 SP 2. are available. The letter D in front of the section name is used to specify a double channel. Front-to-front double channels are similarly added by adding FR in front of the section name.5 Double Channels Back to back double channels.5 In the above commands. members 17 to 27 are a back-to-back double channels C300X90X10 with no spacing in between. Members 45 to 76 are a double channels C250X90X11 with a International Design Codes Manual — 567 .12C.0 28 TO 30 TA FR C200X90X8 SP 2. 20 TO 25 TA ST T250X19 12C. with or without a spacing in between them.4 Channels Channel sections are specified as follows. The standard angle specification is as follows. 12C. In the case of an equal angle.4.7 Double angles Short leg back-to-back and long leg back-to-back double angles may be specified by using the words SD or LD in front of the angle size. the word RA (Reverse Angle) should be used instead of ST as shown below. The spacing between the angles may be specified by using the word SP after the angle size followed by the value of the spacing. For example.6 Angles Two types of specification may be used to describe an angle.Steel Design Per 2002 AIJ spacing of 2 length units.0 WT 6.Pro .8 Tubes Tube names are input by their dimensions.4. all in millimeters.5. 8 TO 25 TA SD L100X65X7 SP 2. 7 TO 23 TA RA L90X75X9 12C.5 length units.0 The first example indicates a short legs back-to-back double angle comprised of 100X65X7 angles separated by 2 length units. The letter L (signifying that the section is an angle) is followed by the length of the legs and then the thickness of the leg. The latter is a long legs back-to-back double angle comprised of 300X90X11 angles separated by 3 length units. The word ST signifies that the section is a standard angle meaning that the major principal axis coincides with the local YY axis specified in Chapter 1 of Section 1. Members 28 to 30 are front-to-front double channels C200X90X8 with a spacing of 2. either SD or LD will serve the purpose.12C. Japanese Codes .0 36 TO 45 TA LD L300X90X11 SP 3.4. 12C. 6 TA ST TUBE DT 8.0 TH 0.2 of the Technical Reference Manual. 1 4 TA ST L150X90X9 If the minor principal axis coincides with the local YY axis specified in Chapter 2 of the User's Manual.5 568 — STAAD. is a tube that has a height of 8 length units. 12C.10 Circular Hollow sections Circular hollow sections defined by JIS G3475:2005 Design Standard for Steel Structures Based on Allowable Stress Concept as Architectural pipe sections are specified as shown in the following example. no member selection. 12C. Only code checking.0 mm and a thickness of 7. 1 TO 9 TA ST PIPE PIP267. 12C.12 Square Hollow sections Square hollow sections defined by JIS G3466:2005 Design Standard for Steel Structures . Sample Input file containing Japanese shapes International Design Codes Manual — 569 . 12C.0 mm. Only code checking.4.0 specifies a pipe with outside diameter of 267.4X16 specifies a pipe with outside diameter of 660.4 mm and a thickness of 16. width of 6 length units and a wall thickness of 0.11 Rectangular Hollow sections Rectangular hollow sections defined by JIS G3466:2005 Design Standard for Steel Structures Based on Allowable Stress Concept are specified as shown in the following example.Based on Allowable Stress Concept are specified as shown in the following example. a width of 100 mm.4. and a thickness of 12 mm. Only code checking. no member selection can be performed on TUBE sections. can be performed on CHS sections. can be performed on PIPE sections. Only code checking.4.4X7. no member selection. 1 TO 9 TA ST PIPE SHS200XS00X12 specifies a square tube with a width of 200 mm and a thickness of 12 mm.9 Pipes (General Pipe sections) Circular hollow sections defined by JIS G3444:2005 Design Standard for Steel Structures Based on Allowable Stress Concept as general pipe sections are specified as shown in the following example.0 mm. 1 TO 9 TA ST PIPE RHS200X100X12 specifies a tube with a depth of 200 mm. no member selection.4. can be performed on CHS sections. Only code checking. no member selection.5 length units. 1 TO 9 TA ST PIPE CHS660. can be performed on CHS sections. Steel Design Per 2002 AIJ STAAD SPACE UNIT KIP FEET JOINT COORD 1 0 0 0 12 11 0 0 MEMB INCIDENCE 1 1 2 11 UNIT INCH MEMBER PROPERTY JAPANESE * H-SHAPE 1 TA ST H200X100X4 * I SHAPE 2 TA ST I250X125X10 * T SHAPE 3 TA ST T200X19 * CHANNEL 4 TA ST C125X65X6 * DOUBLE CHANNEL 5 TA D C200X90X8 * REGULAR ANGLE 6 TA ST L100X75X7 * REVERSE ANGLE 7 TA RA L90X75X9 * DOUBLE ANGLE .LONG LEG BACK TO BACK 8 TA LD L125X75X7 SP 2.0 * DOUBLE ANGLE .12C.0 ID 2. These depend on several factors such as cross sectional properties.Pro .5 PRINT MEMBER PROPERTIES FINISH 12C. It is a method for proportioning structural members using design loads and forces. Japanese Codes . allowable stresses. 570 — STAAD.5 * TUBE 10 TA ST TUBE DT 3.0 WT 2.SHORT LEG BACK TO BACK 9 TA SD L300X90X11 SP 1. allowable compressive stress etc.25 * PIPE 11 TA ST PIPE OD 3. and design limitations for the appropriate material under service conditions.5 Member Capacities Member design and code checking per AIJ 2002 are based upon the allowable stress design method. The basic measure of member capacities are the allowable stresses on the member under various conditions of applied loading such as allowable tensile stress.5 TH 0. 5.2 Methodology For steel design. Calculation of actual and allowable stresses Allowable stresses for structural steel under permanent loading shall be determined on the basis of the values of F given in the following table. For calculation of i ( radius of gyration needed for bending ). 12C. iz using appropriate formula.1-Table: Values of F (N/mm 2) Steel for Construction Structures Thickness SN400 SNR400 STKN400 SN490 SNR490 STKN490 Steel for General Structures Steel for Welded Structu SN490 SNR490 STKN490 SS400 STK400 STKR400 SS490 SS540 SM400 SMA400 SM520 SSC400 t≤ 40 235 325 235 275 375 235 325 355 International Design Codes Manual — 571 . H shape and Channel sections. Moment of Inertia about Y axis and Z axis ( Iyy.1 Design Capabilities All types of available shapes like H-Shape. iy. Prismatic section etc. 12C.5. 2. program calculates moment of inertia ( Ii )and sectional area ( Ai ) for 1/6th section and then uses following formula: i = √(Ii/Ai) Note: The above mentioned procedure for calculation of i is applicable for I shape. TUBE. L-Shapes. 1.slenderness factors. Izz) from in-built Japanese Steel Table and calculates Zz. Calculation of sectional properties The program extract sectional properties like sectional area ( A ). STEEL TABLE available within STAAD or UPTABLE facility can be used for member property. can be used as member property and STAAD will automatically adopt the design procedure for that particular shape if Steel Design is requested. Zy. unsupported width to thickness ratios and so on. The design procedure consist of following three steps. Explained here is the procedure adopted in STAAD for calculating such capacities. CHANNEL. I-Shape. Table 12C. PIPE. STAAD compares the actual stresses with the allowable stresses as required by AIJ specifications. allowable stresses specified in this chapter may be increases by 50% Program calculates actual and allowable stresses by following methods: i. Japanese Codes .Steel Design Per 2002 AIJ Steel for Construction Structures Thickness SN400 SNR400 STKN400 SN490 SNR490 STKN490 Steel for General Structures Steel for Welded Structu SN490 SNR490 STKN490 SS400 STK400 STKR400 SS490 SS540 SM400 SMA400 SM520 SSC400 40< t ≤ 100 215 295 215 255 215 295 335 Note: In checking members for temporary loading be the combination of stresses described in Chap.6 x F)) Δ=F v = 3/2 + 2/3x(λ/Δ 2 ) ii.0. Bending Stress: 572 — STAAD. T NSF = Net Section Factor for tension Actual compressive stress ( F ) = Force / A C Allowable tensile stress ( f ) t = F / 1.4x(λ/Δ 2 )} x F/v when λ ≤ Δ = 2.12C.3.5 (For Permanent Case) = F ( For Temporary Case ) Allowable compressive stress (fc) = {1 .5 (for Temporary case) where: Δ = √(π2 E/(.Pro . Axial Stress: Actual tensile stresses ( F ) = Force / ( A x NSF ).77 x F/ (λ/Δ 2 ) when λ > Δ = fc x 1. 75 .05 (M2 / M1) + 0.Z cz are section modulus for compression Z . f y bty z btz bcz = 1.Actual bending stress for My for compression ( Fbcy ) = My / Zcy Actual bending stress for Mz for compression ( Fbcz) = Mz / Zcz Actual bending stress for My for tension ( Fbty ) = My / Zty Actual bending stress for Mz for tension ( Fbtz ) = Mz / Ztz Where: Z cy ty .4 x (lb / i)2 / (C λ2 )} ft max = 900/ (lb x h / Af ) For Temporary case. f Where: C = 1.. Shear Stress Actual shear stresses are calculated by the following formula: qy = Qy / Aww Where: A ww = web shear area = product of depth and web thickness qz = Qz / Aff Where: International Design Codes Manual — 573 . Z are section modulus for tension tz Allowable bending stress for M (fbcy ) = ft y Allowable bending stress for Mz (fbcz) = { 1 . f Allowable bending stress for M .3 (M2 / M1)2 Allowable bending stress for M .1. iii.5 x (f bcz for Permanent case) =f =f t bcz Note: The parameter CB can be used to specify a value for C directly. Example: 574 — STAAD.0) is used for checking design requirements The following conditions are checked to meet the AIJ specifications.0) is used for checking design requirements The following conditions are checked to meet the AIJ specifications. Axial compressive stress ratio = FC / fc iii.3 Output Format ( TRACK 3 ) One new output format has been introduced which provides details step by step information of Steel Design for guiding load case only.Steel Design Per 2002 AIJ A = flange shear area = 2/3 times total flange area ff Allowable shear stress. Combined tension & bending ratio = Fbcz/fbcz+Fbcy /fbcy . Shear stress ratio for qy = qy / fs viii. If section command is not used design information will be printed for two ends only. For all the conditions calculated value should not be more than the value of RATIO. Checking design requirements: User provided RATIO value (default 1.5. If for any condition value exceeds RATIO . Note: This output format is available only when the BEAM parameter value is 0 and the TRACK parameter value is 3. If for any condition value exceeds RATIO.12C. program gives the message that the section fails. If Section command is used before Parameter command this output will provide details information for all the sections specified by Section Command. f = F / 1. Conditions: i.FT/ft vii. 1. Combined compression & bending ratio = FC / fc+Fbcz/fbcz+Fbcy /fbcy iv. program gives the message that the section fails. Combined compression & bending ratio = (Fbtz+Fbty -FC) / ft v. Checking design requirements: User provided RATIO value (default 1.5. Japanese Codes . von Mises stress ratio (if the von Mises stresses were set to be checked) = f /(k f ) m t 12C. For all the conditions calculated value should not be more than the value of RATIO. Shear stress ratio for qz = qz / fs ix.Pro . Combined tension & bending ratio = (FT+Fbtz+Fbty ) / ft vi. If Member Truss option is used no Shear Design information will be printed. F = F / √(3) s s s 3. Axial tensile stress ratio = FT / ft ii. 1 (1) of the AIJ code. unsupported length of the compression flange (UNL. 12C.0 ALL PARAMETER CODE JAPANESE 2002 BEAM 0.1 (4) of the code.1 (2) of the code.6 Combined Loading For members experiencing combined loading (axial force. 12C. The allowable stresses in shear are computed according to Clause 5. STAAD calculates the tension capacity of a given member based on a user supplied net section factor (NSF-a default value of 1. bending and shear).5. the tensile load must not exceed the tension capacity of the member.SECTION 0.75 1. the actual member length will be used.0 ALL TMP 0.25 0. The allowable stresses in bending (compressive and tensile) are calculated as per the criteria of Clause 5.7 Allowable stress for Shear Shear capacities are a function of web depth. In members with axial tension. thickness of flanges. LY. Compressive resistance is a function of the slenderness of the cross-section (Kl/r ratio) and the user may control the slenderness value by modifying parameters such as KY.5.5. web thickness etc.0 is present but may be altered by changing the input value.5 0. 12C.6 Allowable stress for Bending The permissible bending compressive and tensile stresses are dependent on such factors as length of outstanding legs. In the absence of user provided values for effective length.1 (3). 12C. KZ and LZ. The slenderness ratios are checked against the permissible values specified in Chapter 11 of the AIJ code. The tension capacity of the member is calculated on the basis of the member area.0 MEMB 5 TO 8 TRACK 3 ALL CHECK CODE ALL FINISH 12C.1) and proceeds with member selection or code checking. applicable interaction formulas are checked at different locations of the member for all modeled loading International Design Codes Manual — 575 .4 Allowable stress for Axial Tension Allowable axial stress in tension is calculated per section 5.0 MEMB 1 TO 4 TMP 1.5 Allowable stress for Axial Compression The allowable stress for members in compression is determined according to the procedure of section 5. defaults to member length) etc.5. see Table 8B.0 0. 7 Design Parameters The user is allowed complete control over the design process through the use of parameters mentioned in Table 9B. Note: Once a parameter is specified. Design only for end moments or those at locations specified by the SECTION command. BEAM 0. CB 0 C value from the AIJ code.2.1 is used. Depending on the particular design requirements of the situation.2-Japanese Steel Design Parameters Parameter Name CODE Default Value Description - Must be specified as JAPANESE 2002 to invoke the AIJ 2002. some or all of these parameter values may have to be changed to exactly model the physical structure. Japanese Codes .1 of the Technical Reference Manual. See section 5. Any other value be used in lieu of the program calculated value. and use the maximum Mz location for design. its value stays at that specified number until it is specified again. This is the way STAAD works for all codes. These parameters communicate design decisions from the engineer to the program. For members with axial compression and bending. See "Member Capacities" on page 570 Bending Stress for how C is calculated and applied. the criteria of clause 6.0 to direct the program to calculated Cb. The default parameter values have been selected such that they are frequently used numbers for conventional design. 12C.Steel Design Per 2002 AIJ situations. Use 0. Calculate moments at twelfth points along the beam. 1.12C. Table 12C.0 Locations of design: 0.1 of this chapter. 576 — STAAD. Design Code to follow. Members subjected to axial tension and bending are checked using the criteria of clause 6.Pro .48. K value in local z-axis. Perform check for slenderness 1. denoting starting point for calculation of "Deflection Length" (See Note a) Joint No. International Design Codes Manual — 577 . Length in local y-axis to calculate slenderness ratio. K value in local y-axis. Same as above except in z-axis DJ2 End Joint of member DMAX 100 cm DMIN 0.0 cm KY 1. Usually.0 Net section factor for tension members. allowable local deflection DJ1 Joint No. 1.Parameter Name DFF Default Value Description None (Mandatory for deflection check) Start Joint of member "Deflection Length" / Maxm. Perform Von Mises stress check. Minimum allowable depth for member. Usually. this is the major axis. this is the minor axis. Do not include check.0 LZ FYLD MAIN Yield strength of steel in Megapascal. denoting end point for calculation of "Deflection Length" (See Note a) Maximum allowable depth for member.0 KZ 1. Check for slenderness: 0.0 LY Member Length Member Length 235 MPA 0. Suppress slenderness check MISES 0 Option to include check for von Mises stresses 0. NSF 1. Japanese Codes .12C. TMP 0 Loading condition: 0.Steel Design Per 2002 AIJ Parameter Name RATIO Default Value Description 1. UNF 578 — STAAD. UNL Member Length 1. = Print maximum details.0 Level of output detail: 0. Sidesway in local y-axis. Note: Only produces results when BEAM 0 is used.0 SSZ TMAIN 0. = Suppress critical member stresses 1. Sidesway: 0. No sidesway SSY 0. Any value greater than 1 = Allowable KL/r in tension. = Print all critical member stresses 2. = Print expanded output 3. = Perform and print deflection check.0 Permissible ratio of the actual to allowable stresses. Permanent Loading 1. 4.Pro . 1. Temporary Loading TRACK 0. Same as above provided as a fraction of actual member length. Allowable Slenderness Limit for Tension Member 1.0 = suppress slenderness check .0 Unsupported length for calculating allowable bending stress.0 400 Same as above except in local z-axis. A straight line joining DJ1 and DJ2 is used as the reference line from which local deflections are measured. The “Deflection Length” for all three members will be equal to the total length of the beam in this case. moments are calculated at every twelfth point along the beam. c. In addition. The above parameters may be used in conjunction with other available parameters for steel design.12C. If DJ1 and DJ2 are not used. 2. Code checking is done using forces and moments at specified sections of the members. PARAMETERS DFF 300. The parameters DJ1 and DJ2 should be used to model this situation. location (distance from start joint) and magnitudes of the governing forces and moments are also printed. Thus. DJ1 should be 1 and DJ2 should be 4. "Deflection Length" is defined as the length that is used for calculation of local deflections within a member. and the maximum moment about the major axis is used. The adequacy is checked per the AIJ requirements. D = Maximum local deflection for members 1. for all three members here. in some situations. refer to the figure below where a beam has been modeled using four joints and three members. governing load case. If the BEAM parameter for a member is set to 1.7. the critical condition. the "Deflection Length" may be different. When no sections are specified and the BEAM parameter is set to zero (default). "Deflection Length" will default to the member length and local deflections will be measured from original member line. and 3. However. International Design Codes Manual — 579 . It may be noted that for most cases the "Deflection Length" will be equal to the length of the member. ALL DJ1 1 ALL DJ2 4 ALL b. 12C. The code checking output labels the members as PASSed or FAILed.1 Notes a. design will be based on the forces at the start and end joints of the member. For example.8 Code Checking The purpose of code checking is to check whether the provided section properties of the members are adequate to carry the forces transmitted to it by the loads on the structure. indicates that the left-hand side in the equation should be less than unity. or members listed as PRISMATIC. Sample Input data for Steel Design UNIT METER PARAMETER CODE JAPANESE 2002 NSF 0. The section selected will be of the same type as that specified initially.2 of the Technical Reference Manual for details the specification of the Code Checking command.2 MEMBER 3 4 RATIO 0. The von Mises stress equation shown below.3 of the Technical Reference Manual for details the specification of the Member Selection command.9 Member Selection The member selection process basically involves determination of the least weight member that PASSes the code checking procedure based on the forces and moments obtained from the most recent analysis. a member specified initially as a channel will have a channel selected for it.5 of the Technical Reference Manual for general information on Code Checking. which is modified for beam elements based on the corresponding equation in AIJ steel design code (both 2002 and 2005 editions of AIJ). Refer to Section 5.0 MEMBER 7 KY 1.9 ALL TRACK 1. PIPES. Refer to Section 2.85 ALL UNL 10. Japanese Codes . Note: Member selection cannot be performed on TUBES. Refer to Section 5. 580 — STAAD. For example.6 of the Technical Reference Manual for general information on Member Selection. Selection of members whose properties are originally provided from a user table will be limited to sections in the user table. 12C. The default is set that this check is not performed.07 or higher. The MISES parameter must be set to 1 to initiate the checks.48.48.Steel Design Per 2002 AIJ Refer to Section 2.10 Von Mises Stresses Check Note: This feature requires STAAD.Pro V8i (SELECTseries 2) build 2007.Pro .12C.0 ALL CHECK CODE ALL SELECT ALL 12C. These checks are performed at locations indicated by the BEAM parameter. When its left-hand side yields the maximum ratio value. stress value of (numerator of the von Mises stress equation) is output as the value of fm.Note: As with other design checks. x Z = Section modulus about y-axis y z Z = Section modulus about z-axis τxy = Mx Zx + Fy Ay 2 + Fz Az 2 M = Torsional moment x F = shear stress in y direction y z F = shear stress in z direction Z = Torsional section modulus = 2I /D x x x D = Depth of the member x I = Torsional constant x A = Effective shear area in the y direction y z A = Effective shear area in the z direction f = Allowable tensile stress t In the STRESSES output category. The von Misers stresses are evaluated and checked as follows: σx + 3τ xy f 2 2 < 1. International Design Codes Manual — 581 . it is printed as RATIO and “VON MISES” is printed as CRITICAL COND.0 Where: Longitudinal stress in beam element: σx = Fx Ax + My Zy + Mz Zz F = Axial force x M = Bending moment about y-axis y z M = Bending moment about z-axis A = Cross-sectional area. and deflections. Along with slenderness ratios. the unity check value can be modified by use of the RATIO parameter. von Mises stress equation is checked. stresses. Pro .582 — STAAD. Section 13 Mexican Codes International Design Codes Manual — 583 . 584 — STAAD.Pro . 13A. l l l Columns — Prismatic (Rectangular.1 . It will calculate the reinforcement needed for the specified concrete section. ZD 20. (Normas Técnicas Complementarias para Diseño y construcción de Estructuras de Concreto) of the Mexican Construction Code for the Federal District –Aug. Mexican Codes .Pro is capable of performing concrete design based on the Mexican code NTC 1987 Normas Técnicas Complementarias para Diseño y construcción de Estructuras de Concreto (Complementary Technical Norms for Design and Construction of Concrete Structures).13A. and T-shapes Walls — Finite element with a specified thickness Figure 13A. 1993 (Reglamento de Construcciones para el Distrito Federal). IZ 53333 IY 13333 International Design Codes Manual — 585 . Trapezoidal. All the concrete design calculations are based on the current: Complementary Technical Standards for the Design and Construction of Concrete Structures – Nov. 13A.1 Design Operations STAAD has the capabilities for performing concrete design.Concrete shape nomenclature for beams and columns 13A. The following example shows the required input: UNIT CM MEMBER PROPERTY 13 TO 79 PRISM YD 40. Square.Concrete Design Per MEX NTC 1987 STAAD.3 Member Dimensions Concrete members which will be designed by the program must have certain section properties input under the MEMBER PROPERTY command.2 Section Types for Concrete Design The following types of cross sections can be defined for concrete design. and Circular) Beams — Prismatic (Rectangular & Square). 1987. Design of members per NTC 1987 requires the STAAD Latin American Design Codes SELECT Code Pack. For concrete design.13A. Mexican Codes . beams and columns are designed for moments directly obtained from the analyses without any magnification. trapezoidal or Tshaped and the BEAM design will be done accordingly. ZB 12. Note that no area (AX) is provided for these members. Note that the third and the fourth set of members in the above example represent a T-shape and a TRAPEZOIDAL shape respectively.1 is a complete list of the available parameters and their default values. 586 — STAAD. YB. this property must not be provided. the program will determine whether the section is rectangular. This is the way STAAD works for all codes. ZD 18.2 of the Technical Reference Manual. Similarly. For example. Depending on the properties (YD. 17 TO 19 PR YD 24. ZB. ZD. etc. 13A. The factors MMY and MMZ may be used for magnification of column moments. Notice that in the above example the IZ and IY values provided are actually 50% of the values calculated using YD and ZD. Default parameter values have been selected such that they are frequently used numbers for conventional design requirements. the program calculates these values from YD and ZD. ZD 48. Design Code to follow. the values of SFACE and EFACE (parameters that are used in shear design). ZB 12. YB 18.Pro .) provided. with only depth and no width provided. This is a conventional practice which takes into consideration revised section parameters due to cracking of section. are assigned values of zero by default but may be changed depending on the actual situation. the first set of members are rectangular (40 cm depth and 20 cm width) and the second set of members. 14 TO 16 PRIS YD 24. the user may generate load cases which contain loads magnified by the appropriate load factors.1-Mexican Concrete Design Parameters Parameter Name CODE Default Value Parameters - Must be specified as MEXICAN. will be assumed to be circular with 20 cm diameter. the distances of the face of supports from the end nodes of a beam. The manual describes the commands required to provide these parameters in the input file. Note: Once a parameter is specified.4 Design Parameters The program contains a number of parameters which are needed to perform design by the Mexican code. These values may be changed to suit the particular design being performed. its value stays at that specified number until it is specified again.Concrete Design Per MEX NTC 1987 11 13 PR YD 20.52. See section 5. If shear areas and moments of inertias are not provided. In the above input. Table 13A. For beams. Table 3. 1 NTC l l FALSE .Not cold formed bar TRUE .I 2nd paragraph l l DCP TRUE FALSE .Loads applied indirectly TRUE . in current units.5.4.5 NTC Concrete TRUE: Precautions are taken to assure dimensions l International Design Codes Manual — 587 . IMPERIAL (No 3 to 18) 1.1. Beam Loads and reactions in direct compression Cl-2.Direct compression DEPTH YD Depth of concrete member.a.Parameter Name BTP Default Value Parameters 2 Bar type to use: 0. l DIM TRUE FALSE: Not precautions taken Section reduction to section 1.1d) to define Modulus of Elasticity 1. Class 2 Concrete CFB FALSE Cold formed Bar classification to define development multipliers according to table 3. MEXICAN (No 2 to 18) CCL 1 Concrete class according to 1.Cold formed bar CLB CLS CLT DAG 3 cm 3 cm 3 cm 2 cm Clear cover for bottom reinforcement Clear cover for side reinforcement Clear cover for top reinforcement Maximum diameter of aggregate. in current units. METRIC (4. This value defaults to YD as provided under MEMBER PROPERTIES. Class 1 Concrete 2.2 to 60mm) 2. 200 Kg/cm 2 Compressive Strength of Concrete Yield Stress for main reinforcing steel Yield Stress for secondary (stirrup) reinforcing steel Part of the longitudinal steel considered to reduce shear.Exposed to soil or weather l FC FYMAIN FYSEC 200 Kg/cm 2 4. Mexican Codes .Pro . geometric or confinement ones) l l FALSE .Lightweight concrete MAXMAIN 12 Maximum main reinforcement bar size (Number 2 -18) Minimum main reinforcement bar size (Number 2 -18) MINMAIN 2.1 NTC l l LSS 0 LTC FALSE FALSE .Not exposed to soil or weather TRUE . for the time being.Ductile Frames EFACE 0 Face to support location of end of beam. Some design conditions are considered (not including.5 588 — STAAD.Concrete Design Per MEX NTC 1987 Parameter Name DSD Default Value Parameters TRUE Ductile frames in accordance with Section 5 of the code. Value between 1 and 0.Non-Ductile frames TRUE . Light Concrete to define development multipliers according to table 3. 0 (zero) is conservative.13A. for shear force at start is computed at a distance of EFACE+d from the start joint of the member.Regular concrete TRUE . If specified.200 Kg/cm 2 4. Positive number. Exposition to soil or weather to define cover and min Steel reinforcement l EXP FALSE FALSE . 2 Tied Column. about Mz.000 Kg/cm 2 12 NSECTION Number of equally-spaced sections to be considered in finding critical moments for beam design Stirrups angle with the axis of the element Slab beared perimeter. MMY 1. A value of 1 will mean spiral. If specified. Positive number Beam needed for torsional equilibrium Cl.0 MOE 198. Concrete modulus of elasticiy. To calculate min steel required according to 2.5 Minimum secondary reinforcement bar size (Number 2 -18) Moment magnification factor for columns. for shear force at start is computed at a distance of SFACE+d from the start joint of the member.No TRUE .1.Yes International Design Codes Manual — 589 . Face to support location of start of beam. about My.0 MMZ 1.Parameter Name MINSEC Default Value Parameters 2.2. Moment magnification factor for columns.1.6a) 2nd paragraph l l PHI 90 degrees PSS TRUE REINF 0 SFACE 0 TEQ FALSE FALSE . 6 mm. will print out a schematic interaction diagram and intermediate interaction values in addition to all of the above.13A. Critical Moment will not be printed out with beam design report. Note: When using metric bars for design. 8 mm. in current units. all active beam loadings are prescanned to locate the possible critical sections. Will print out detailed design results. 13A. Will mean a print out. The following metric bar sizes are available: 4. 25 mm. 50 mm and 60 mm. shear and torsion. 32 mm. All of these equally spaced sections are scanned to determine moment and shear envelopes. Will print out required steel areas for all intermediate sections specified by NSECTION. 16 mm.Pro . 2. 1. 590 — STAAD. Mexican Codes . 2. The total number of sections considered is 12 (twelve) unless this number is redefined with an NSECTION parameter. WIDTH ZD Width of concrete member. provide values for these parameters in actual ‘mm‘ units instead of the bar number. 10 mm.Concrete Design Per MEX NTC 1987 Parameter Name TRACK Default Value Parameters 0 Beam Design 0. 1.2mm. Column Design 0. 12 mm. For all these forces. This value defaults to ZD as provided under MEMBER PROPERTIES * These values must be provided in the current unit system being used. 40 mm. 20 mm. Will mean a print out column interation analysis results in addition to TRACK 0 output.5 Beam Design Beams are designed for flexure. due to design conditions could be 2 or 4-legged. In case the program selects 2 different diameters for the main or compression reinforcement. of the main reinforcement calculated under flexural design.4 Output Level Serial number of bar level which may contain one or more bar group International Design Codes Manual — 591 . Clauses 2.1). that is if the required reinforcement is greater than the maximum allowable for the cross section. the number of bars and the distance over which they are provided are calculated. The moment MY is not considered in the flexural design. These values are reported as ROW.2.1. It is important to note that beams are designed for flexural moment MZ only. 3. ROWMX and ROWMN in the output and can be printed using the parameter TRACK 1. Note that the value of the effective depth "d" used for this purpose is the update value and accounts for the actual c.5. Note that the coordinates of these START and END points are obtained after taking into account the anchorage requirements.10 and 5.(Clear cover + diameter of stirrup + half the dia.0 (see Table 13A. Effective depth is chosen as Total depth . the program reports that beam fails in maximum reinforcement.1. If the section dimensions are inadequate to carry the applied load. Based on the total stirrup reinforcement required.2 of NTC Concrete are utilized to obtain the actual amount of steel required as well as the maximum allowable and minimum required steel.4 of NTC Concrete are used to calculate the reinforcement for shear forces and torsional moments. the anchorage details are also provided. the maximum. of main reinforcement). The relevant clauses in Sections 1. 1. SFACE and EFACE have default values of zero unless provided under parameters (see Table 13A. Shear forces are calculated at a distance (d+SFACE) and (d+EFACE) away from the end nodes of the beam. Anchorage length is calculated on the basis of the Clauses described in Section 3. 13A.5. 13A. At any particular level. 13A.5.5.2 Design for Shear Shear reinforcement is calculated to resist both shear forces and torsional moments.5-6 and 5.1-2-5.3 Design for Anchorage In the output for flexural design. 2. the spacing.2. the size of bars.g. In addition. Rectangular sections are also designed with compression reinforcement.13A.1 Design for Flexure Reinforcement for positive and negative moments are calculated on the basis of the section properties provided by the user. the START and END coordinates of the layout of the main reinforcement is described along with the information whether anchorage in the form of a hook or continuation is required or not at these START and END points.6. only the anchorage for the largest diameter is analyzed. Stirrups due to geometric conditions are assumed to be 2-legged. minimum and actual bar spacing are also printed.1).5.1 of NTC concrete. and a trial value is obtained by adopting proper bar sizes for the stirrups and main reinforcements. FLEXURE PER CODE NTC FOR THE DESIGN AND CONSTRUCTION OF CONCRETE STRUCTURES. Mexican Codes . is needed at the start (STA) or at the end (END).DDF LEN . SIZE . Row Actually required flexural reinforcement (As/bd) where b = width of cross section (ZD for a rectangular or square section) and d = effective depth of cross section (YD minus the distance from extreme tension fiber to the centroid of main reinforcement). ROWMN Minimum required flexural reinforcement (Amin/bd) ROWMX Maximum required flexural reinforcement (Amax/bd) Spacing Distance between centers of adjacent bars of main reinforcement Vu Factored shear force at section Vc Nominal shear strength provided by concrete Vs Nominal shear strength provided by shear reinforcement Tu Factored torsional moment at section Tc Nominal torsional moment strength provided by concrete Ts Nominal torsional moment strength provided by torsion reinforcement Example Output for Beam Design ===================================================================== BEAM NO.75(mm) LEVEL HEIGHT BAR INFO FROM TO ANCHOR (mm) (mm) (mm) STA END _____________________________________________________________________ 592 — STAAD.Concrete Design Per MEX NTC 1987 Height Height of bar level from the bottom of the beam Bar Info Reinforcement bar information specifying number of bars and bar size From Distance from the start of the beam to the start of the reinforcement bar To Distance from the start of the beam to the end of the reinforcement bar Anchor (STA/END) States whether anchorage.6000.13A. either hook or continuation.253.Pro . FC 20. 2 DESIGN RESULTS .75 X 253.00(mm) FY 412. If PNMAX is less than the axial force Pu/FR.00 KN Vs= 0. 212. Minimum eccentricity conditions to be satisfied according to section 2. the column moments are multiplied by the corresponding MMAG value to arrive at the ultimate moments on the column.1. Muy.a are checked. bar arrangement and axial load. independently.2.00 Kn Me LOAD STIRRUPS ARE NOT REQUIRED. Solve the Interaction Bresler equation: (Mny /Mycap )α + (Mnz/Mzcap )α Where α = 1.MM 5 . 4.00 Kn Me Ts= 0.3. Fc.003 Steps involved: 1. Fy Ultimate Strain for concrete : 0. Method used: Bresler Load Contour Method Known Values: Pu.MM 2468. D.Vu= 5. Column design is done for square. These values are referred to as MYCAP and MZCAP respectively. find International Design Codes Manual — 593 . reinforcement is always assumed to be equally distributed on all faces. rectangular and circular sections. 2.2.00 KN Vs= 0. 1 1 13A.09 Kn Me Tc= 0.2 ) is a good amount to start with.63 KN Vc= 0. find the uniaxial moment capacities of the column for the Y and the Z axes. Ensure that the actual nominal load on the column does not exceed PNMAX.2.SHEAR AT START SUPPORT . Assume some reinforcement.09 Kn Me Tc= 0. If the Interaction equation is satisfied. 6000. For rectangular and circular sections. the column cannot be designed with its current dimensions. If the MMAGx & -MMAGy parameters are specified. 2 D E S I G N R E S U L T S . 5 . 3.24.63 KN Vc= 0. NO YES YES NO B E A M N O. This means that the total number of bars for these sections will always be a multiple of four (4). Minimum reinforcement (1% for ductile design or according to section 4.00 KN Tu= 0.6 Column Design Columns design in STAAD per the Mexican code is performed for axial force and uniaxial as well as biaxial moments. 0. If the column is subjected to uniaxial moment: α = 1 6.00 KN Tu= 0. where Po is the maximum axial load capacity of the section. 5. Calculate PNMAX = Po.00 Kn Me LOAD STIRRUPS ARE NOT REQUIRED. If the reinforcement exceeds 6% (or 4% for ductile design). find an arrangement with available bar sizes. 2782. (FR is the strength reduction factor) increase the reinforcement and repeat steps 2 and 3. Muz. AT END SUPPORT . Find an approximate arrangement of bars for the assumed reinforcement. All active loadings are checked to compute reinforcement.Vu= 5.1 2 42. Clear cover. B. For the assumed reinforcement. The loading which produces the largest amount of reinforcement is called the critical load.00 Kn Me Ts= 0. The values printed for the TRACK 1. 7.19.0 or TRACK 2.700 (PROVIDE EQUAL NUMBER OF BARS ON EACH FACE) 594 — STAAD.0 is used for the TRACK parameter. the assumed reinforcement is increased (ensuring that it is under 6% or 4% respectively) and steps 2 to 6 are repeated. Mu = Ö (Mux.700 BAR CONFIGURATION REINF PCT.NUMBER 5 1. Pnmax = Maximum allowable axial load on the column. In the case of circular columns. Mexican Codes . M_bal = Uniaxial moment capacity of balanced strain condition. P_tens = Maximum permissible tensile load on the column. the values are for any of the radial axes.4 (mm) TIED AREA OF STEEL REQUIRED = 626. for the actual reinforcement that the column has been designed for. E_bal = M_bal / P_bal = Eccentricity of balanced strain condition. each representing a different point on the Pn-Mn curve are printed.9 FC .8 Column Design Output The next table illustrates different levels of the column design output. If a value of 2. Des. 13A.Mmagy)² e/h = (Mn/Pn)/h where h is the length of the column l l l 13A.6 MPa SQRE SIZE 25.0 for the column member. the reinforcement details are written to the output file. 12 different Pn-Mn pairs.411.13A.230 1 END 0.Concrete Design Per MEX NTC 1987 the uniaxial capacities and solve the interaction equation again.4 x 25. If the interaction equation is not satisfied. Des.Mmagx)²+ (Muy.7 Column Interaction The column interaction values may be obtained by using the design parameter TRACK 1.Pro .0 output are: l l l l l l l l P0 = Maximum allowable pure axial load on the column (moment zero). By the moment to check shear and torsion for columns the sections have to be checked as beams and the most strict of both shear and torsion reinforcement adopted. P_bal = Axial load capacity of balanced strain condition. LOAD LOCATION PHI ---------------------------------------------------------4 . The output is generated without any TRACK specification: ==================================================================== COLUMN NO. 1 DESIGN PER MEX NTC-87 . Pn = Pu/FR where FR is the Strength Reduction Factor and Pu is the axial load for the critical load case. M0 = Moment capacity at zero axial load. If the equation is satisfied now.AXIAL + BENDING FY .Mnx = Mux*MMAGx/FR where FR is the Strength Reduction Factor and Mu is the bending moment for the appropriate axis for the critical load case. Each of these points represents one of the several Pn-Mn combinations that this column is capable of carrying about the given axis. 00 161168.91 27205616.(cm) 2095196.50 11408365.50 16296947.84 28901764.00 Pn | * 1128182. M-bal.95 24433192.00 Pn.69 27278232.00 | * 1611689.62 23117562.62 | * 1289351.00 P0 |* 1772858.81 29473708.2 M0 P-tens.00 -550620.00 NOMINAL| * AXIAL| * COMPRESSION| * Pb|-------*Mb | * ___________|____*_______ | * M0 Mn.00 483506.max|__* 1450520.00 0. | * BENDING International Design Codes Manual — 595 .50 967013.75 28658428.00 40.38 727411.00 644675.00 805844. e-bal.TRACK=1 generates the following additional output: COLUMN INTERACTION: MOMENT ABOUT Z/Y -AXIS (Kg-cm ) -------------------------------------------------------P0 Pn max P-bal.62 25462606.00 20083028. Des.Pn 'Des.00 20000000.12 29235398.38 2095196.38 5373253.Mn e/h 20606994.00 322337.00 NaN -------------------------------------------------------- TRACK=2 generates the following output in addition to all the above: Pn Mn Pn Mn | 1934027. and EXP listed in Table 11A.Concrete Design Per MEX NTC 1987 P-tens|* MOMENT 13A.00 / 0 0.44 / 1 0. FC. FY. CLB.MM/MM) (KN-MM/MM) 47 TOP : Longitudinal direction .00 / 0 BOTT: 0.35 / 1 47 SHEAR CAPACITY 57.06 KN ***PASS*** FOR LOAD CASE 3 ***** INDICATES REINFORCEMENT EXCEEDS MAXIMUM ***************************END OF ELEMENT DESIGN*************************** 596 — STAAD. REINF MOM-X /LOAD TRANS. design is not performed at any other point on the surface of the element.MM/MM) (KN-MM/MM) (SQ. Element design will be performed only for the moments MX and MY at the center of the element. A typical example of element design output is shown below. CLS. MXY. 47 TOP : 0.254 10. Mexican Codes . DIM.13A. 47 TOP : Transverse direction . The parameters FYMAIN. it must be modeled using finite elements. Other parameters mentioned are not used in slab design.2 .1 Example Output for Element Design ELEMENT DESIGN SUMMARY ---------------------ELEMENT LONG. Figure 13A. CLT. Shear is checked with Q. REINF MOM-Y /LOAD (SQ.205 0.Element moments: Longitudinal (L) and Transverse (T) 13A.9. FXY. The reinforcement required to resist Mx moment is denoted as longitudinal reinforcement and the reinforcement required to resist My moment is denoted as transverse reinforcement. Also.9 Slab Design Slabs are designed per Mexican NTC specifications. Design will not be performed for FX.Only minimum steel required.1 are relevant to slab design.Only minimum steel required.205 0.362 13. To design a slab.Pro . The following sections describe the salient features of the Mexican specifications as implemented in STAAD steel design. Because the different factors reflect the degree of uncertainty of different loads and combinations of loads and of the accuracy of predicted strength. The Limit States Design Method uses separate factors for each load and resistance. a more uniform reliability is possible. A brief description of the fundamental concepts is presented here. desired section type.1 General The design philosophy considered is that of the Load Cases and Resistance Method or Limit States Design usually known as Load and Resistance Factor Design (LRFD). 1993).Pro is capable of performing steel design based on the Mexican code NTC 1987 (Normas Técnicas Complementarias para Diseño y construcción de Estructuras Metálicas) (Complementary Technical Standards for the Design and Construction of Steel Structures – Dec. members are proportioned to resist the design loads without exceeding the limit states of strength. Appropriate load and resistance factors are used so that a uniform reliability is achieved for all steel structures under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. 13B. The primary considerations in ultimate limit state design are strength and stability. Two major categories of limit-state are recognized--ultimate and serviceability. The code checking portion of the program checks that main code requirements for each selected section are met and identifies the governing criteria. 13B. The method may be summarized by the inequality Yi Qi ≤ Rn FR International Design Codes Manual — 597 . the most economic section is selected on the basis of the least weight criteria as augmented by the designer in specification of allowable member depths. Mexican Codes . Accordingly.2 Limit States Design Fundamentals The primary objective of the Limit States Design Specification is to provide a uniform reliability for all steel structures under various loading conditions. or other such parameters. while that in serviceability is deflection. Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use. 1987) or the Reglamento de Construcciones para el Distrito Federal (Mexican Construction Code for the Federal District –Aug. Design of members per NTC 1987 requires the STAAD Latin American Design Codes SELECT Code Pack. and stability.Steel Design Per NTC 1987 STAAD. It allows to check deformation to verify serviceability.13B. In the STAAD implementation of the Mexican Standards for steel structures. Y . it is assumed that the user will use appropriate load factors and create the load combinations necessary for analysis. FR. STAAD is capable of determining the section classification for the standard shapes and design accordingly. Refer to Section 1. 13B. Thus local buckling becomes an important criterion. the required strength is the summation of the various load effects. The design procedures are different depending on the section class. Steel sections are classified as compact (type 2). multiplied by a resistance factor.3 Member End Forces and Moments Member end forces and moments in the member result from loads applied to the structure. that always refers to the gross section. noncompact (type 3).).6 Axial Compression The column strength equations take into account inelastic deformation and other recent research in column behavior.Steel Design Per NTC 1987 On the left side of the inequality. etc. STAAD immediately does a slenderness check on appropriate members before continuing with other procedures for determining the adequacy of a given member. the following figures show the member end actions with their directions. Q .Pro . This classification is a function of the geometric properties of the section.4 Section Classification The Limit States Design specification allows inelastic deformation of section elements. 13B. 13B. STAAD calculates the tension capacity of a given member based on these two limit states and proceeds with member selection or code check accordingly.13B. bracing member. or slender element (type 4). In calculation of resistances of various elements (beams. 13B. The design portion of the program will take into consideration the load effects (forces and moments) obtained from analysis. R . n In the STAAD implementation of the Mexican Standards.5 Member in Axial Tension The criteria governing the capacity of tension members is based on two limit states. In addition to the tension resistance criterion. The limit state of yielding in the gross section is intended to prevent excessive elongation of the member. is the nominal strength or resistance.19 of the Technical Reference Manual for additional details. one for 598 — STAAD. on the right i i side. Mexican Codes . The design strength. In both the member selection and code checking process. multiplied by their respective load factors. These forces are in the local member coordinate system. columns etc. sections depending upon their local buckling characteristics. The net section area may be specified by the user through the use of the parameter NSF (see Table 13B. the user defines if tension members are required to satisfy slenderness limitations which are a function of the nature of use of the member (main load resisting component. besides sections type 1 are able for plastic design. Two equations governing column strength are available. The second limit state involves fracture at the section with the minimum effective net area. resistance (nominal strength) and applicable resistance factor will be automatically considered.).1). STAAD immediately does a slenderness check on appropriate members before continuing with other procedures for determining the adequacy of a given member. the procedure described in Section 2. Both equations include the effects of residual stresses and initial out-of-straightness. the flexural design strength of a member is determined mainly by the limit state of lateral torsional buckling.8 of the NTC For the sections where the web and flange are slender the LRDF USA specification was used. bracing member. It is taken into account the reduction of flexural resistance due to slender web according to section 4. the entire member length will be taken into consideration.1) can be used. Inelastic bending is allowed and the basic measure of flexural capacity is the plastic moment capacity of the section. To specify laterally unsupported length. For slender elements. compression members are required to satisfy slenderness limitations which are a function of the nature of use of the member (main load resisting component.NTC is also used.6. The limiting laterally unbraced length Lu and flexural resistance Mr are functions of the section geometry and are calculated as per the procedure of Section 3. Stress areas due to bending about y axis (MY) International Design Codes Manual — 599 . buckling moment and the bending coefficient.Julio 1993) were implemented for the determination of design strength for these limit states.2 of the NTC. This coefficient can be specified by the user through the use of parameter CB or CBy (see Table 11B. KZ and/or LY.2 of the Commentaries. The procedures of Section 3. The purpose of bending coefficient Cb is to account for the influence of the moment gradient on lateral-torsional buckling. a default value of 1.7 Flexural Design Strength In the Limit States Design Method. either of the parameters UNL and UNF (see Table 10B. In both the member selection and code checking process.3. LZ. In addition to the compression resistance criterion. If not provided. limiting laterally unbraced length.inelastic buckling and the other for elastic or Euler buckling. ayudas de diseño y ejemplos de las Normas Técnicas Complementarias para el Diseño y Construcción de Estructuras Metálicas.0.1) or may be calculated by the program (according to LRDF USA specification) if CB is specified as 0. Effective length for calculation of compression resistance may be provided through the use of the parameters KY. Compression strength for a particular member is calculated by STAAD according to the procedure outlined in Section 3. design helps and examples of the Complementary Technical Standards for the Design and Construction of Steel Structures (de los Comentarios.2 of the NTC.0 will be used.3. 13B.5. etc. The flexural resistance is a function of plastic moment capacity.). In the absence of the parameter CB. actual laterally unbraced length. DDF (Comentarios . 4 of the NTC. 600 — STAAD. the Global Y axis is vertical upwards.3. These interaction formulas cover the general case of biaxial bending combined with axial force..6/7 of the NTC.5. Stress areas due to bending about Z axis (MZ) 13B.3.Pro .9 Combined Compression Axial Force and Bending The interaction of flexure and axial forces in singly and doubly symmetric shapes is governed by formulas of the Section 3.3 of the NTC is used in STAAD to design for shear forces in members. 13B. considering also the limits for stiffeners of the web according to sections 4. the shaded area indicates area under compression. Besides combined bending and shear is checked according to section 3.4 of the NTC. They are also valid for uniaxial bending and axial force.13B. Shear in wide flanges and channel sections is resisted by the area of the web/s.Steel Design Per NTC 1987 Note: The local X axis goes into the page.8 Design for Shear The procedure of Sect. Mexican Codes . 3. the area not shaded indicates area under tension. Steel Parameter Name CODE Default Value Description - Must be specified as MEXICAN. The default parameter values have been selected such that they are frequently used numbers for conventional design. These parameters communicate design decisions from the engineer to the program and thus allow the engineer to control the design process to suit an application's specific needs.11 Design Parameters Design per Mexican Standards is requested by using the CODE.1-Design Parameters According to Mexican NTC Standards . See section 5.48. some or all of these parameter values may be changed to exactly model the physical structure. 13B. It is taken into account if the elements have transverse loads and if the ends are angularly restrained.1 of the Technical Reference Manual. BEAM 0 0: Design at ends and those locations specified by SECTION command. Design Code to follow.It is considered that the frames are part of structures that have shear walls or rigid elements so that the lateral displacements of a floor could be disregarded. This is the way STAAD works for all codes. Table 13B. The parameters DMAX and DMIN may only be used for member selection only. 1: Design at ends and at every y cada 1/12th point along member length International Design Codes Manual — 601 . 13B. its value stays at that specified number till it is specified again.10 Combined Tension Axial Force and Bending Based on Section 3. Other applicable parameters are summarized in Table 11B. Once a parameter is specified. Depending on the particular design requirements.1 below. The program has included formulas to include structures with lateral displacements in the future considering for B2 the columns individually and not the complete floor analysis.5 4 of the NTC. 2. Section 3.3.85 = Members ends are not restricted angularly.0 = Members ends are restricted angularly. DMAX DMIN 114 cm 0.13B.Pro . denoting end point for calculation of "Deflection Length. Any other value will be directly used in the design. Joint No.0 it will be calculated by the program according to LRFD USA (CbMex=1/CbUSA).0 cm Maximum allowable depth Minimum allowable depth 602 — STAAD. Cfactor for combined forces when there are transverse loads in the members.4." See Note 1 below.3. CMB 1 DFF None (Mandatory for deflection check.2. DJ1 DJ2 End Joint of member Joint No.ii of NTC CMB 1. If Cb is set to 0. TRACK 4. Mexican Codes .Steel Design Per NTC 1987 Parameter Name CB Default Value Description 1 Coefficient C defined per section 3. CMB 0.0) Start Joint of member "Deflection Length" / Maxm.3. allowable local deflection See Note 1 below." See Note 1 below. denoting starting point for calculation of "Deflection Length . laminated I shapes.230 Kg/cm 2 2. 0.3. n=1.Parameter Name DSD Default Value Description T Perform the ductile seismic design in accordance with Section 11 (True or False). defined for I shapes or tubes 0.2. tubes or built up with 3 or 4 welded plates obtained from wider plates cuts with oxygen. geometric ones) FU FYLD IMM 4. 1. tubes or built up with 3 or 4 welded plates IRR 0 Variable defined for the whole structure indicating if it is regular or irregular according to section 3.0 Effective length factor for flexural-torsional buckling International Design Codes Manual — 603 .4.4 of the NTC. Secondary and wind trusses INO 0 Curve Definition according to NTC. I shapes. Columns that are part of irregular structures KX 1.1a.2. at the moment. n=1. Columns that are part of regular structures 1. Main design conditions are considered (not including. Main member 1.530 kg/cm 2 0 Ultimate tensile strength of steel Minimum Yield strength of steel Main or secondary member for the purpose of checking slenderness 0. = Print expanded design output KZ 1. = Suppress all design strengths 1.Usually major axis Defines if the structure has elements to bear the wind load (shear walls. Mexican Codes . or bracing rigid elements ) that restrict lateral displacements and allow to disregard slenderness effects.13B.Pro .Usually minor axis Effective length factor for local Z axis. (True or False) Length for determining flexuraltorsional buckling Length to calculate slenderness ratio for buckling about local Y axis. Length to calculate slenderness ratio for buckling about local Z axis. wind trusses.Steel Design Per NTC 1987 Parameter Name KY Default Value Description 1.0 LDR T LX Member length LY Member length LZ Member length NSF 1 RATIO 1. Net section factor for tension members Permissible ratio of actual load effect and design strength Spacing of stiffeners for beams for shear design Controls the level of detail in output 0. = Print all design strengths 2.0 Effective length factor for local Y axis.0 STIFF Longer of Member length or depth 0 TRACK 604 — STAAD. DJ1. and DJ2 from Table 2B. Refer to Section 5. Refer to Section 2.48.5 of the Technical Reference Manual for general information on Code Checking. For deflection check. 2.0. 13B. Refer to Section 2.13 Tabulated Results of Steel Design Results of code checking and member selection are presented in a tabular format.12 Code Checking and Member Selection Both code checking and member selection options are available in STAAD Mexican Standards implementation. member design strengths will be printed out. UNT Member length Unsupported length (L) of the top* flange for calculating flexural strength . International Design Codes Manual — 605 . Top and Bottom represent the positive and negative side of the local Y axis (local Z axis if SET Z UP is used).2 of the Technical Reference Manual for details the specification of the Code Checking command. CRITICAL COND refers to the section of the Mexican NTC which governed the design. If the TRACK is set to 1. Will be used only if compression is in the bottom flange. parameters DFF.6 of the Technical Reference Manual for general information on Member Selection. All requirements remain the same.48. See Note 2 below. 13B. 1.3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 5.1 may be used. See Note 2 below. Will be used only if compression is in the top flange.Parameter Name UNB Default Value Description Member length Unsupported length (L) of the bottom* flange for calculating flexural strength . 606 — STAAD.Pro . Section 14 Norwegian Codes International Design Codes Manual — 607 . 608 — STAAD.Pro . 1 . Eurozone Design Codes SELECT Code Pack. IPE etc.General Notes This user manual presents a description of the design basis. HEB. [1] and NPD ref. Sist enderet 1. tube. channel and RA angle) The code check is not available for the following cross-section types: l l l l Double angles Tapered tubes Prismatic sections with too few section parameters defined Other sections that are not in the ‘available’ list above Please note the following: l NS 3472 and NPD code checking covered in this document are available through two separate STAAD. Design of members per NS 3472 / NPD requires the STAAD N.Pro is capable of performing steel design based on the Norwegian code NS 3472 Steel structures. I-sections. Norwegian Codes .Pro Code check packages. Revision 1). (Guidance on the design. HUP) channel angle type (only RA) rectangular massive box (prismatic) user table (wide flange.Pro for performing code checks according to NS 3472 ref. calculation and dimensioning of figures constructions. Design rules (3rd Edition) and NPD 1993 Veiledning om utforming. 14A. [5].Steel Design per NS 3472 / NPD STAAD. tapered I. beregning og dimensjonering av stalkonstruksjoner. parameters and theory applied to STAAD.14A. The code checks include: l l l l stability check (buckling) lateral buckling check yield check (von Mises) stability check including local plate buckling of un-stiffened pipe walls according to NPD The code check is available for the following cross-section types: l l l l l l l wide flange profiles (HEA. International Design Codes Manual — 609 .) pipe (OD xx ID xx) tube (RHS. refers to NS 3472 ref. NS 3472 3.Steel Design per NS 3472 / NPD l This document is not a lecture in use of NS 3472 or NPD. The prismatic section defined in the code check (rectangular massive box) is not identical to the general prismatic profile defined in the STAAD.14A. [6] NPD . l l l EDR does not accept any liability for loss or damage from or in consequence for use of the program.1 Nomenclature NS . 1994 Veiledning om utforming.utg. This document explains how.Pro Technical Reference Manual. Roark &Young`s 5th edition 5.utg. STAAD. This manual describes the procedures and theory 610 — STAAD.Basis for Code Checking This section presents general information regarding the implementation of the Norwegian codes of practice for structural steel design. NS 3472 1.utg. and which parts of. Norwegian Codes . 2001 Prosjektering av stålkonstruksjoner Beregning og dimensjonering 2. beregning og dimensjonering av stålkonstruksjoner.Pro analysis package. [5] 14A.1984 Prosjektering av stålkonstruksjoner Beregning og dimensjonering 14A. 1973 Prosjektering av stålkonstruksjoner Beregning og dimensjonering 4.refers to NPD94 ref.1.Pro . NS 3472 2. Release 2002 3. Weld design is not included in the Norwegian code checks.2 References 1. the Norwegian steel codes that have been implemented in STAAD. 6. oktober 1993.1. the Code Check requires RA angle definition. [1] NS2 . When L-sections are used. Sist endret 1.refers to NS 3472 ref.2 .Pro. 14A. NPD utg. Section 3. The user is allowed complete control over the design process through the use of the parameters listed in Table 2. International Design Codes Manual — 611 . An exception is the treatment and check of pipe members in framed structures.7 Stability is checked as per the procedure of NS 12.value will be according to NS table 11. 3 have been incorporated into the STAAD. In addition. axial tension capacity is checked for the ultimate limit stress.used for both NS and NPD. etc. 14A.4 explains how this is adopted when NS is selected for code checking. 14A. axial compression capacity is checked in addition to lateral buckling and ultimate limit stress.1 Calculation of Forces and Bending Moments Elastic analysis method is used to obtain the forces and moments for design. In the absence of parameters CY and /or CZ. web crippling.2. Analysis is done for the primary loading conditions and combinations provided by the user. Default values of parameters will yield reasonable results in most circumstances.Pro code check. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary load combinations. For compression members. and consider the effect of local buckling of the pipe wall in conjunction with the stability check. However. It is generally assumed that the user will take care of the detailing requirements like the provision of stiffeners and check the local effects like flange buckling.1. The coefficient α (as per NS Table 10) can be specified in both directions through the use of parameters CY and CZ. The largest slenderness ratio (λ) shall not be greater than 250 according to NS 11. the NPD code gives joint capacity formulae for brace to chord connections for pipe members. the user should control the design and verify results through the use of the design parameters. In general NS is used for all cross sections and shapes listed in section 1 of this manual. The design philosophy and procedural logistics are based on the principles of elastic analysis and ultimate limit state design. Two major failure modes are recognized: l l failure by overstressing failure by stability considerations The following sections describe the salient features of the design approach.3. The NPD however have a more thorough check of pipe members. default a.2. The buckling curves of NS fig. Members are proportioned to resist the design loads without exceeding the characteristic stresses or capacities and the most economic section is selected on the basis of the least weight criteria.2 Members with Axial Forces For tension only members. NS does not give specific details about the treatment of pipes. 14A.3. NS 3472 The material factor default value is 1. Conditions for sidesway and transverse loading can be specified through the use of parameters SSY and SSZ. coefficients b are calculated and proper dimensioning moments are used in the interaction formulae.6 Material factor and nominal stresses The design resistances are obtained by dividing the characteristic material strength by the material factor.2. 14A. without transverse loading. The coefficient can be provided by the user through the use of parameter CB. Torsional properties for cross sections (torsional constant and warping constant) are calculated using formulae from NS 3472.2. In the absence of CB. bending. interaction formulae of NS table 12.4 Lateral Buckling Lateral torsional buckling is checked as per the procedure of NS 12.Steel Design per NS 3472 / NPD 14A. The nominal stresses should satisfy σj ≤ fy γm = fd 612 — STAAD. All compression capacities are calculated per the procedure of NS 12. The program will automatically select the maximum moment in cases where Mvd is less than Mzd.Pro .4.5 Von Mises Yield Criterion Combined effect of axial.0 will be used. For members that cannot sway.2 are checked for appropriate loading situation. The equivalent moment factor β is calculated using the procedure of NS table 12. The procedure for calculation of ideal buckling moment for sections with two axis of symmetry has been implemented. 14A. Two different approaches are used depending upon whether the members can sway or not. The von Mises calculates as: σj = (σx + σ by + σbz) 2 + 3(τx + τ y + τ z) ≤ 2 fy γm 14A. The worst stress value is checked against yield stress divided by appropriate material factor.4. a value of 1.3. Norwegian Codes .3 Members with Axial Force and Bending Moments For compression members with bending.10. This results in slightly conservative estimates of torsional parameters.3. horizontal/vertical shear and torsional shear stress is calculated at 13 sections on a member and up to 9 critical points at a section. Other values may be input with the MF parameter.2.2. NPD The general requirement is according to NPD 3.4.1. Control of nominal stresses. including interaction with overall column buckling (NPD 3. c. e. 3.7 and 3. b.3). bending.4.Pro implemented NPD code this is calculated automatically.4.2). check b) assumes that stresses resulting from shear and torsion are of minor importance.0 for frames.7 Code checking according to NPD The following parts of Chapter 3 in the NPD guidelines have been implemented.4. In other words.2.6. torsion or shear.4.2. The interaction between global and local buckling due to axial load and hydrostatic pressure is accounted for through computation of an axial characteristic capacity to replace the yield stress inn the beam-column buckling formulae.2.1. For stability the NPD 3.9).1.5.1.2.7.4. circumferential compression or tension.3 requires that the structural coefficient is considered. 14A.2).2.g.4. 3.1. a. Joint capacity check for gap as well as for overlap joints (NPD 3. 3. The stability requirement is given in NPD 3. including interaction with local shell buckling (NPD 3. In the STAAD. d.. S d ≤ fkd = fk γ m ⋅ γ mk (S d) Where: S = reference stress or load effect resultant d f = characteristic capacity k f kd m = design capacity = material coefficient = structural coefficient γ γ γ m mk is default set to 1. The unity check refers to the interaction formulae in NPD 3.1 and 3. in jacket braces. Check c) provides the unity check based on the stability requirement for un-stiffened cylindrical shells subjected to axial compression or tension. (NPD 3.4. Note: Check b) handles members subjected to axial loads.2. bending moments and hydrostatic pressure. Buckling of un-stiffened closed cylindrical shells. Buckling of pipe members in braced frames. Check b) provides the unity check based on the beam-column buckling interaction formulae in NPD 3. γ shall be equal to 1.1. For pipe members γ is a function of the reduced mk mk slenderness. International Design Codes Manual — 613 .10. 3 614 — STAAD. Design Code to follow.Pro input file.Steel Design per NS 3472 / NPD 14A.3 BZ 1. NS > 0.0 BY 1.0 and 9.0 Parameter BEAM 1.48.0) Fig. β. (Depending on what kind of shape is used. The yield check is the same as for steel. For heat-treated use CY = CZ = 0.2 Note: Must be set to 1.0) 12.1590. 14A.0 Buckling length coefficient. They are set to default values to begin with and may be altered to suite the particular structure. Norwegian Codes .1-Design Parameters for Norwegian Steel design code Parameter Name CODE Default Value none Description Reference Must be secified as either NS3472 for NS or NPD for NPD (NOR may also be used for both). NS 12.0 print buckling curve H for heat-treated.14A.8 Aluminum Check STAAD. Tracks 1.2.2. See section 5. Table 14A. and up to 8 points at each section.2420. NS 3 strong axis buckling (z-z) (NOTE: BZ Sec.Pro performs a stability check on aluminum alloys according to buckling curve in ECCS (European recommendation for aluminum ally structures 1978).1 of the Technical Reference Manual. It is possible to select heat-treated or non heat-treated alloy from the parameter list in the STAAD. and for non heat-treated use CY = CZ = 0.0 ALL tells the program to calculate von Mises at 13 sections along each member.0 Buckling length coefficient.) Sec.3 Design Parameters Design parameters communicate specific design decisions to the program. NS 12. for Fig. β for weak axis buckling (y-y) (NOTE: BY > 0. NS 3 Sec.Pro . and buckling curve N for non neat-treated. BEAM 0. NS2 A5.5.Parameter Name CB Default Value 1.3.0 Description Reference Lateral buckling coefficient. NS 10. d curve. NS 3 Sec. DMAX 100. γ m (NS3472) 1.4 Fig.49 CY CZ Default see NS 3472 Buckling curve coefficient. NS 12.0 = Sidesway in local y-axis weak axis β M International Design Codes Manual — 615 . NS 12. NS 12.1.1 RATIO Sec.3. a0. NS2 A5.4 Sec.3. Y.4 Tab.15 (NPD) 1.0 [cm] 0. Represent the a.4 Tab. NPD 3.3. NS 6.2 Sec. Minimum allowable depth of steel section.0 SSZ 0.2.1 Material factor / Resistance factor. Used to calculate the ideal buckling moments. NS 12 Sec NPD 3. b. NPD 3.0 Water depth in meters for hydrostatic pressure calculation for pipe members α for sections in connection with LT lateral buckling CMZ 0.4. NS 12. Yield strength of steel.2 Fig. β calculated.0 = Sidesway in local y-axis weak axis β =SSY M Sec.4. fy (St37) [N/mm2 ] Tab. > 0. 0. NS 12 Sec. > 0. β calculated.2.2 NS Table 11 CMY 1. c.2a)-e) Valid for the NPD code only Sec. a about local z-axis (strong axis).0 0.0 [cm] Maximum allowable depth of steel section. NS 12.0 Permissible ratio of the actual to allowable stresses.1. NS 3 DMIN FYLD 235 MF 1.2 Sec. M vi Sec. Fig.4 SSY 0.0 = No sidesway.5.0 = No sidesway. 3. 14A. NS 12.10 ALL CY 0. See ".0 = Print von Mises stresses.49 MEMB 1 616 — STAAD. * CODE CHECK ACCORDING TO NS3472 PARAMETERS CODE NS3472 BEAM 1.14A. DESIGN VALUES 2. 1 page for each member.Steel Design per NS 3472 / NPD Parameter Name TRACK Default Value 0. define an inside pressure in pipe members.0 = Suppress critical member stresses. Distance between fork supports or between effective side supports for the beam Sec. 5.0 = Print all critical member stresses. i.2.3 The parameter CMY will. Norwegian Codes .0 Description Reference Controls the level of detail in the output: 0.Pro ..0 = Large output. 9. NS app. UNL Member length Effective length for lateral buckling calculations (specify buckling length). The pressure corresponds to given water depth in meters. The parameter CB defines the φ value with respect to calculation of the ideal lateral buckling moment for single symmetric wide flange profiles.Tabulated Results" on page 648 for complete list of available TRACKs and print examples.0 ALL FYLD 340 ALL MF 1.e. ref.2. used at the end of the input file. when given with negative value. 1.1 Example Note: This is a partial example containing only the information pertaining to the Norwegian steel design code. NS Tab. Buckling lengths and results for member with joints between the structural nodes have to be evaluated in each separate case.1 MEMB 1 SSZ 1.0 ALL UNIT KNS METER LOAD LIST 1 CHECK CODE MEMB 1 FINISH 14A.3 MEMB 1 CB 0. Effects from local buckling or external hydrostatic pressure on pipes and tubes are not included. The general stability criteria is: (ref.1 Buckling nmax + kz × mz + ky × my ≤ 1 14A.4.49 MEMB 1 BY 0.4.2 Lateral Buckling n χy + kLT mz χ LT + k ym y ≤ 1 Where: i = z.i/Nd ki = 1−µi n χ iγ m ≤ 1.CZ 0.7 MEMB 1 SSY 1.9 β Mi ref.9 MEMB 1 BZ 0.4) ≤ 0.χy ) χi = Nkd.4 Stability Check According to NS 3472 The stability check is based on the assumption that both ends of the member are structural nodes. NS 12.5 μi = λi(2·βMi .9 MEMB 1 RATIO 1.3) 14A. 12 International Design Codes Manual — 617 .0 ALL TRACK 9.y nmax = n/χmin n = Nf/Nd χmin = min(χz. 51 + α λLT − 0.8 .1 λLT = W zfz M cr Mcr = ψ·Mvio ψ ref.0 μLT = 0.3. NS Tab 10 & 11 χLT = 1 2 ϕ LT + ϕ LT − λ LT 2 2 ϕLT = 0.14A.5.4 + λLT ( ) α ref. Norwegian Codes . NS2 A5.3 Determination of β and β z y The equivalent moment factor β (for z and y) is calculated dependant on moment distributions as shown in the following table: Table 14A.2) + λ2 ] α ref.5[1 + α(λ .0.0.15(λy ·βM .Pro .1) ≤ 0. NS sec.4.d M vio = π L EI zGIT 1 + π EC w L 2 GI T 2 14A.7ψ M (β ) LT 618 — STAAD.2 Sect.4. a . 12.Steel Design per NS 3472 / NPD kLT = 1 − µ LT n χ yγ m ≤ 1.2-β for different moment distributions Moment diagram β Mψ β = 1.9 λi = λi/λ1 λi = Lki/ii λi = π χi = E fy 1 ϕ+ ϕ −λ 2 2 φ = 0. Moment diagram β M0 β = 1.6C w Ix concern double symmetric cross sections where y is given in NS fig. see section 5. L = member length for lateral buckling (input parameter UNL).4 Lateral buckling The Ideal lateral buckling moment is calculated according to NS2 A5. ψ ) M0 = |Mmax | due to transverse load only ΔM = |Mmax | if the moment has the same sign ΔM = |Mmax | + |Mmin | if the moment changes sign The user can override the calculated factor with the following parameters: βy =SSY βz=SSZ 14A.2 M vi = ψM vio = ψL95 E L I Ix 1 + π 2 L2 2. For single symmetric cross sections.2. Cw and Ix .4. A5. ψ + M0 ∆M (β M. (input parameter CB).4 βM = βM .039L 2I T Iy International Design Codes Manual — 619 .3 M (β ) LT β M0 = 1. the ideal lateral buckling moment is M vix = ϕ π 2EI y L 2 ( 5a π 2 + rx 3 2 5a − ys + C 2 − 2 + π ) rx 3 − ys Where: C2 = C w + 0.5.5.0 − βM . assumed to be on top flange. The φ parameter (ref NS fig. A5.Pro .1 .2. Norwegian Codes .Steel Design per NS 3472 / NPD α = distance from profile CoG to point where the load is acting.5.ψ-coefficients for a simple span beam 620 — STAAD.14A. Figure 14A.g) is controlled by the input parameter CB. ψ-coefficients for a partially restrained beam International Design Codes Manual — 621 .2 .Figure 14A. 14A.Pro .Steel Design per NS 3472 / NPD Figure 14A.ψ-coefficients for a fully restrained beam 622 — STAAD.3 . Norwegian Codes . 4 . N kzd N kyd M and M are given in NS 5.0 K E 1.4.0 and M vd M d 14A.Figure 14A.6 Angle profiles type RA (reverse angle) The axial contribution to the total interaction ratio is checked according to the modified EECS-method. see NS A5.4.5 Stability check of pipe members The stability criteria applied for members with pipe cross section is: 2 My Mz + + ≤ 1. 14A. Dashed curves apply load on the surface.2.0 M 1 − N N M 1 − d d N Ezd N Eyd 2 IR = N N kd Where: N N kd N N = max .4.4.ψ-coefficients for the cantilevered beam with single loads and distributed loads. z z For the print output option TRACK 9. The stability criterion is: International Design Codes Manual — 623 . I values are taken from the middle of the member.5) is not included in the code check. 14A.8 Lateral buckling for tension members When compressive stress caused by large bending moment about strong axis is greater than tension stress from axial tension force. respectively.4.0 Where: N N kd N N = max .60 + 0.7 Stability check of members with tapered section Stability of members with tapered cross section is calculated as described in section 3.Steel Design per NS 3472 / NPD IR = N N kd + My N M yd1 − N Eyd + Mz N M zd1 − N Ezd ≤ 1. Norwegian Codes . ..1.14A. (i.57λ For λ > √(2) λeff = λ Where: λ= λk π fy E λk = lk /i i = I/ A Possible lateral buckling effects and torsional buckling (NS A5. σa = N/A (+ tension.4.Pro .max /Myd ≤ 1.4.0 624 — STAAD.4. For λ ≤ √(2) λeff = 0.and z-axis. N kzd N kyd kzd N kyd and N are found from NS 3472 fig.compression) σbz = ± Mz/W z Mwarp = | σa + σb | W z for σa + σb < 0 (compression) IR = Mwarp /Mvd + My. The cross section properties used in the formulae are calculated based on the average profile height. This has to be evaluated by the user separately. I .) z y 14A. lateral buckling is considered as defined below.la C-curve for y.e. 5. members subjected to axial compression only d t ≤ 0.μ). the yield strength will be replaced with characteristic buckling stress given in NPD 3.14A.4 International Design Codes Manual — 625 . members subjected to axial compression and external pressure d t ≤ 0. curve A.2 2 σcγmk + Bσ * b + (B zσ bz) + (B yσ by) ≤ 2 fy γm Where: σ = N/A = axial compressive stress c ν mk = structural coefficient z y B = bending amplification factor = 1/ (1 .1 E fy 14A.Stability Check According to NPD 14A.1 Buckling of pipe members Tubular beam-columns subjected to compression and lateral loading or end moments shall be designed in accordance with NPD 3.4.5.2.4. 5. B is taken as the larger of B and B B = bending amplification factor about the Z-axis z B = bending amplification factor about the Y-axis y µ = σc / fE fE = π 2E 2 lk 2 i i = I/ A σ* b = σc fy fk − 1 1 − fk γ mfE l = kl k k = effective length factor f = characteristic buckling capacity according to NS fig.3 Calculation of buckling resistance of cylinders The characteristic buckling resistance is defined in accordance with NPD 3.3 If the below conditions are not satisfied.2 Interaction with local buckling.2.5 .5. k 14A.5.5 E fy b.1a.4. NPD 3. a. 4 Elastic buckling resistance for un-stiffened. 14A. Norwegian Codes . S f .5.6 is: fe = k 12 1 − ν t ( ( ) l) 2 π 2E 2 626 — STAAD. lateral pressure.4.Pro . and torsional moments and/or shear forces respectively. f . global bending moments. closed cylinders The elastic buckling resistance for un-stiffened closed cylinders according to NPD 3.Steel Design per NS 3472 / NPD fk = fy 1+λ 4 Where: λ = 2 f y σ ao σj fea + σb0 feb + σp 0 fep + τ feτ 2 σ j = (σa + σ b)2 − σa + σ b σ p + σ p + 3τ 2 ( ) σ ≥ 0 when a σa0 = 0 σ < 0 when a σa0 = -σa σ ≥ 0 when b σb0 = 0 σ < 0 when b σb0 = -σb σ ≥ 0 when p σp0 = 0 σ < 0 when p σp0 = σp σ = design axial stress in the shell due to axial forces (tension positive) a σ = design bending stress in the shell due to global bending moment (tension b positive) σ = σ = design circumferential stress in the shell due to external pressure p Θ (tension positive) τ = design shear stress in the shell due to torsional moments and shear force. f and f are the elastic buckling resistances of curved panels or circular ea eb ep eι cylindrical shells subjected to axial compression forces.14A. 5. aspect ratio.04 Z0. circumferential compression or tension.5 1. ζ.04 Z0. Table 14A.5 Stability requirements The stability requirement for curved panels and un-stiffened cylindrical shells subjected to axial compression or tension.5. torsion or shear is given by NPD 3. bending. and p are given in Table 4.5 1 + p 1 5.where k is a buckling coefficient dependent on loading condition. It is necessary to take this International Design Codes Manual — 627 .6 1 − ν2 For long shells the elastic buckling resistance against shear stresses is independent of shell length.6 Column buckling.3-Table 4.702 Z 0. For cases with: 1 r > 3.75 1.7: σj < fkd where the design buckling resistance is fkd = fk γ mγ mk 14A.5 0. NPD 3.1 Buckling coefficients for un-stiffened cylindrical shells ψ Axial or Bending stress Torsion and shear force Lateral pressure Hyrdostatic pressure The curvature parameter is defined by Z= 1 rt 2 ζ 0.34 4 2 ( r −0.25E ( rt ) 2 14A. and geometrical imperfections. curvature. The buckling coefficient is: k = ψ 1+ ( ) ψ pξ 2 The values of ψ.1 for the most important loading cases.85 r t the elastic buckling resistance may be taken as: fep = 0.4.9 For long cylindrical shells it is possible that interaction between shell buckling and overall column buckling may occur because second-order effects of axial compression alter the stress distribution as compared to that calculated from linear theory.856 Z0. boundary conditions.5 150t ) 0.4. The stresses are calculated in several stress points at each member section.2.Steel Design per NS 3472 / NPD effect into account in the shell buckling analysis when the reduced slenderness of the cylinder as a column exceeds 0. σ . p 628 — STAAD. At each stress point the von Mises stress is checked as follows: 2 σ j = σ 2 o + σ p − σ o ⋅ σ p + 3(τ x + τ y + τ z) ≤ 2 fy γm Where: σtot = | σx + σby + σbz | σ stress from hydrostatic pressure. Norwegian Codes . σ shall be increased by an additional compressive stress which may be taken as: b ∆σ = Bσa fy fk − 1 1 − fk fe + B − 1σ b Where: B= 1 1−µ λ = fy / fe fe = π E λ2 2 λ = slenderness of the cylinder as a column.1. a b 14A.6 Yield Check The yield check is performed at member ends and at 11 equally spaced intermediate sections along the member length.4.2.Pro .4. B. σ .2 according to NPD 3. and μ are calculated in accordance with NPD 3. torsional moment along member x M actual bending about local y-axis at section y z M actual bending about local z-axis at section For all profiles other than angle sections absolute values of the stresses are used.14A. At each section the following forces are applied: F max. axial force along member x F actual shear in local y-direction at section y z F actual shear in local z-direction at section M max. For double symmetric profiles there will always be one stress point. Stress points checked for a wide flange section Section Properties A .5 .Pro database x x y z A = h × s Applied in STAAD.Pro print option PRINT MEMBER STRESSES y Az = (2/3)· b · t · 2 τy = Fy /Ay τz = Fz/Az A and A are not used in the code check y z Cw = (h − t ) b t 24 2 3 ref. I .6.1 Double symmetric wide flange profile The von Mises stress is checked at four stress points as shown in figure below. Figure 14A.14A. and I are taken from STAAD. NS app. C3 Ty = dA × z Tz = dA × y Stress calculation General stresses are calculated as: σ = σx + σ by + σ bz = Fx Ax + My Iy z+ Mz Iz y International Design Codes Manual — 629 . I . 14A.6 . Actual torsional stress distribution is largely dependent on surface curvature at stress point and warping resistance.6.Stress points checked for a singly symmetric wide flange section 630 — STAAD. 14A.4-Stress calculations at selected stress points for a wide flange section Point No 1 σ x σ by σ bz τ x τ y τ z My b Iy 2 Mz b Iz 2 Mx Ix 0 t F y bt h 2 I z 2t F y bt h 2 Mx Ix Iz s 0 Fz t b 2 I y 8t 2 Fx Ax 0 0 Mz Iz 3 h1 s 0 4 0 0 2 F y bt h 2 + 0. Norwegian Codes . Figure 14A. The reported torsional stresses are indicative only.5h 1 s ( ) Iz s 0 In general wide flange profiles are not suitable for large torsional moments.Pro . For members with major torsional stresses a separate evaluation has to be carried out.2 Single symmetric wide flange profile and tapered section The von Mises stress is checked at nine stress points as shown in figure below.Steel Design per NS 3472 / NPD τ = τx + τ y + τ z = Mx Ix c+ V yTz I z + VzT y I y Where the component stresses are calculated as shown in the following table: Table 14A. C3 See "Double symmetric wide flange profile" on page 629 for equations used in section property calculations.) A z = 2 / 3(b ⋅ t + b 1 ⋅ t 1) Cw = b t ⋅ b 1 t 1(h − t / 2 − t 1 / 2) 12 b 3 3 2 ( 3 3 t +b 1 t 1 ) ref. (i. I . and I are taken from STAAD.Pro database. Iy values are taken from the middle of the member.Section properties A . Stress calculation See "Double symmetric wide flange profile" on page 629 for equations used in general stress calculations. except for tapered sections x x y z where these values are calculated for each section checked. Iz.. Where the component stresses are calculated as shown in the following table: International Design Codes Manual — 631 . I .e. NS app. 3 Pipe profile The von Mises stress is checked in 3 stress points as shown in figure below. 14A.5-Stress calculations at selected stress points for a singly symmetric wide flange section Point No 1 σ x σ − by σ bz τ x τ y τ z My b Iy 2 Mz Iz Mx Ix 0 h2 t F y bt (h 1 + t / 2) Iz 2t 0 Fz t b 2 I y 8t 2 0 My b Iy 2 3 4 Fx Ax 0 Mz Iz 0 0 0 h1 F y bt (h 1 + t / 2) Iz s 5 0 − 0 Mz Iz Mx Ix 2 F y bt h 1 + t / 2 + 0.5h 1 s s ( ) Iz s F y b 1t 1(h 3 + t 1 / 2) Iz s 0 6 7 − 0 My b 1 Iy 2 h3 0 0 Fz t 1b 2 I y 8t 1 0 − Mz Iz 8 0 My b 1 Iy 2 h4 Mx Ix t F y b 1t 1(h 3 + t 1 / 2) Iz 2t 1 9 0 0 In general wide flange profiles are not suitable for large torsional moments.14A. 632 — STAAD.Steel Design per NS 3472 / NPD Table 14A. For members with major torsional stresses a separate evaluation has to be carried out. Actual torsional stress distribution is largely dependent on surface curvature at stress point and warping resistance.Pro . Norwegian Codes . The reported torsional stresses are indicative only.6. d 2) x A = A = 0.5A x z I = 2I =π/32 (D4 .Figure 14A.d 4) y z International Design Codes Manual — 633 .7 .Stress points for a pipe section Section properties d = D .5 ( D-t ) a = tan-1 M /M Ax = π/4 y z z (D2 y .2t r = 0.d 4) I = I = π/64 (D4 . Steel Design per NS 3472 / NPD Note: In the STAAD. A = A = 0. 634 — STAAD. Norwegian Codes .4 Tube profile Tube sections are rectangular or quadratic hollow uniform profiles. A and I . Critical stress is checked at 5 locations as shown in figure below.6A Y z x I = x 2πR3t Stress calculation at selected stress points 14A.14A.Pro .Pro analysis package slightly different values are used for A .6. however this has insignificant influence on the y z x force distribution. Section Properties International Design Codes Manual — 635 . Steel Design per NS 3472 / NPD Stress calculation at selected stress points The general stress formulation is given in sec.Pro .6.2. 636 — STAAD. Norwegian Codes .14A. 5.5 Channel profile For channel profiles the von Mises stress is checked at 6 locations as shown in the figure below. 14A. International Design Codes Manual — 637 . 5. Norwegian Codes .Pro .f 638 — STAAD.Steel Design per NS 3472 / NPD Cross section properties Stress calculations at selected stress points The general stress formulation is given in sec.2.14A. 14A.6. Axes u and w are local axes. International Design Codes Manual — 639 .6 Angle profile type RA (reverse angle) For angle profiles the von Mises check is checked at 8 stress points as shown in figure below. Axes y and z are principal axes. 14A. The second moment of area (Ty L TZ): T =AZ y z T =AY 640 — STAAD.Pro .Pro analysis are about the principle axis y and z.Steel Design per NS 3472 / NPD Cross section properties Section forces The section forces from the STAAD. Norwegian Codes . x y Z Beta-rotation of equal & unequal legged angles Note: The order of the joint numbers in the member incidence command specifies the direction of the local x-axis.Stress calculation at selected stress points An additional torsional moment is calculated based on: M = F Z4 T T y z M = F Y4 This torsion moment is included in M if F and F exist. International Design Codes Manual — 641 . Pro . Norwegian Codes .14A.Steel Design per NS 3472 / NPD 642 — STAAD. If that is the case. Section Properties International Design Codes Manual — 643 . define the member with h > b and Beta angle 90° instead.14A. The prismatic section is assumed to be a rectangular massive box and the von Mises stress is checked at 3 locations as shown in figure below.Pro analysis package is not available. Note: Note that ‘b’ may not be much greater than ‘h’.7 Rectangular massive box (prismatic) Code check of the general purpose prismatic cross section defined in the STAAD.6. i. the joint capacity checking. The file is an editable ACSII file saved under the file name given in the CODE NPD parameter.2. This file is used as input in the second run. Norwegian Codes .5. case 4 at midpoint the largest side i..4. 20. punching shear capacity is checked in accordance with the NPD sections 3. The joints to be checked will be listed in a file specified in the CODE NPD parameter list. 644 — STAAD. The TRACK parameter is then set to 98 which directs the program to read from the file GEOM1 file and use it as input to the second run. If the diameters are the same the program selects the member with the greater thickness of the two. The chord is defined as the member with the greater diameter in the joint.14A. The program will first identify all tubular joints and classify them as T type joints (TRACK99).e.Steel Design per NS 3472 / NPD General Stress Calculation ref.e.2. The punching shear run sequence is performed in two steps.5.1 to 3. The program will check the capacity for both chord members entering the joint.and out-of plane moments. The local y and z moments will be transformed into the plane defined by the joint itself and the far end joints of the brace and chord. below called GEOM1. except 3. NPD 3. defined as in. The chord members must be collinear by 5 degrees.5.. [4] tab.Pro .5 For pipe members. point 2 Stress calculation at selected stress points 14A.7 Tubular Joint Check. The following symbols are used: T = Cord wall thickness t = Brace wall thickness R = Outer radius of chord r = Outer radius of brace Θ = Angel between chord and considered brace D = Outer diameter of chord d = Outer diameter of brace a = Gap (clear distance) between considered brace and nearest load-carrying brace measured along chord outer surface ß = r/R International Design Codes Manual — 645 .7. gap. yield stress and other geometric options if required. See Appendix A page xx for GEOM1 example file. The required chord wall thickness shall be determined when the other dimensions are given. can or stub dimensions.The ASCII file should be edited to reflect the correct classification of the joints.0 ALL CHECK CODE ALL 14A.1 Static strength of tubular joints The basic consideration is the chord strength. The program will not change the brace or chord definition if this is changed or modified in the input file GEOM1. Joint classification parameters in the file GEOM1 are: KO K joint overlapped KG K joint with gap TY T or Y joint X X joint Input example for the classification run. *CLASSIFICATION OF JOINTS. TRACK 99 UNITS MM NEWTON PARAMETER CODE NPD GEOM1 FYLD 350 ALL TRACK 99 ALL BEAM 1. 0 .1 ß N = Design axial force in brace M M IP = Design in-plane bending moment in brace = Design out-of plane bending moment in brace OP N = Characteristic axial load capacity of brace (as governed by the chord k strength) M = Characteristic out-of-plane bending moment capacity of brace (as OPk governed by the chord strength) σ σ σ ax IP = Design axial stress in chord = Design in-plane bending stress in chord = Design out-of-plane bending stress in chord OP This section gives design formulae for simple tubular joints without overlap and without gussets.1 and Q is a factor to account for the nominal longitudinal stress in u f the chord.03γA2 A2 = 2 2 2 σ ax + σIP + σ OP 0.1 u Q d = See table 6.64f y 2 646 — STAAD.Steel Design per NS 3472 / NPD g = R/T g = a/D f = Yield stress y Q = Factor f Q = See table 6. Qf = 1.14A.0. Norwegian Codes . diaphragms or stiffeners.1 g Q = See table 6. Tubular joints in a space frame structure shall satisfy: N ≤ Nk / γm Where: Nk = Q uQ f f yT 2 sin Θ Q is given in Table 6.Pro . 0. and / or the structural coefficient γ = 1.0 .0. Qβ = 0.045γA2 The characteristic capacity of the brace subjected to out-of-plane bending moment shall be determined by: MOPk = Q uQ f u d f yT sin Θ 2 Where Q is given in Table 6.2/(1-0. When the brace acts as a cantilever c.6.la/T For γ > 20.5 + 19β (2.0. When the rotational stiffness of the connection is considered in the determination of effective buckling length. The characteristic capacity of the brace subjected to in-plane bending moment shall be determined by: MIPk = Q uQ f u d f yT sin Θ 2 Where Q is given in Table 6.0.0 For γ ≤ 20.021γA2 International Design Codes Manual — 647 .0.3.8 . g When β ≥ 0.0.8 . This is also applicable for moment loading.6. Qβ = 1.1 and Qf = 1. This is also applicable for moment loading.7 + 13β)Q 0. The brace end moments shall be accounted for in the following cases: a.9.1.1 and Qf = 1. Qg = 1.3/[β(1 . Out-of-plane bending moment when β > 0. Qf is set to 1.85 b. See Section 3.81β) T and Y X K 2.6-Values for Q Type of joint and geometry u Type of load in brace member Axial In-plane bending 5.00 for the beammk column design of the brace or chord. Q is set to 1.0√(γ)β β Out-of-plane bending 3.0 .90(2+21β)Q β For β > 0.4g but in no case shall Q be taken as less than 1.0.Table 14A. Qg = 1.833β)] For β ≤ 0. For cases with f tension in the chord. Table 14A.Steel Design per NS 3472 / NPD For combined axial and bending loads in the brace. including von Mises stress Brief print of member utilizations (two lines for each member) Comprehensive print with detailed information about member and member utilization(one page for each member) 1 2 3 9 648 — STAAD. 14A.7-Available TRACK parameter values TRACK no. where compression in a brace is essentially balanced by tension in brace(s) in the same side of the joint.Pro . Example prints and explanation to the information / heading given on the print out is given in Appendix A. 0 Description Brief print of member utilizations (2 lines for each member) sorted with highest utilized members first Based on TRACK 3 with additional information regarding stability factors and capacities Simple print of stresses.10) l = circumference for that portion of the brace in contact with the chord l (actual length) l = circumference of brace contact with chord. 3.10 2 The above formula for the capacity of overlapping joints is valid only for K joints.Tabulated Results This section presents a table with the various TRACKs available with respect to print out from the code check. the total load component normal to the chord. neglecting presence of overlap N = characteristic axial load capacity of brace k t = the lesser of the throat thickness of the overlapping weld or the thickness t w of the thinner brace l = length as shown in NPD fig. the following interaction equation should be satisfied: N Nk M IP + M + IPk 2 M OP M OPk ≤ 1 γm For overlapping tubular joints without gussets. diaphragms.14A. 3. or stiffeners. NN. shall not exceed NN = 2f y t wl 2 Nk l1 sin Θ + γm l 3 γm where (see NPD fig. Norwegian Codes .8 . 1 Output for member design Output example for TRACK 0.8. IPE.TRACK no. 99 Description Used in connection with tubular joint check according to NPD. This TRACK identifies tubular joints to be checked and classifies all members entering the joint as T connection Used in connection with tubular joint check according to NPD. This TRACK performs the joint capacity check Prints member end forces for members entering each joint (at the end of the member connected to the joint) Prints maximum and minimum member end forces (axial force defines max and min) at member end 1 Prints maximum and minimum member end forces (axial force defines max and min) at member end 2 98 49 31 32 14A. C = compression) Start moment about the y-axis Description Unit kN kNm kNm kNm kNm kNm MYs MYm Mid moment about the y-axis MYe End moment about the y-axis MYb RATIO LOAD TABLE Buckling moment about the y-axis Interaction ratio The critical load case number Section type (HE.0 Symbol MEMB FX Member number Axial force in the member (T = tension.) International Design Codes Manual — 649 . TUBE. etc. 0 0.34 1 PIPS40 (AISC SECTIONS) 3.9 -15.6 -1.0 0.0 0.0 0.00 4 24.0 0.0 5.2 36.Steel Design per NS 3472 / NPD Symbol MZs Description Start moment about z-axis Unit kNm kNm kNm kNm MZm Mid moment about the z-axis MZe End moment about the z-axis MZb COND DIST Buckling moment about z-axis Critical condition Distance from the start of the member to the critical section m Note: Myb and Mzb are the design moments used for max unity ratio.2 STAB 10.80 C 0.0 0.9 -36.0 0.1 -6.14 3 26.0 0.7 2.00 Output example for TRACK 1.0 1.1 1.1 STAB 0.0 0.5 5.0 Symbol CURVE St Description Buckling curve about the strong axis Unit 650 — STAAD.78 1 PIPS40 (AISC SECTIONS) 5. NS3472 (VERSION 06002) UNITS ARE KN AND METE MEMB FX MYs MYm MYe MYb RATIO LOAD TABLE MZs MZm MZe MZb COND DIST =============================================================================== 1 12.8 38.0 0.0 0.0 0.8 VMIS 0.Pro .8 1.0 0.08 1 FAIL PIPS40 (AISC SECTIONS) 31. Norwegian Codes .0 0.9 2.0 0.14A.9 STAB 14.0 0.30 1 FAIL PIPS40 (AISC SECTIONS) -0.2 -1.4 -2.31 C 0.00 2 4.9 STAB 5.02 T 0.3 2.02 C 0.83 5 5.0 0.20 C 0.0 0.58 1 PIPD60 (AISC SECTIONS) 36.4 -38. 0 0.500 FakY=1.3.2 about the y-axis Moment capacity about the y axis Moment capacity about the z axis Lateral buckling moment Interaction ratio for buckling without lateral buckling (Cl.112E+2 KNM MVD =.251 | |-------------------------------------------------------------------------| 2 4.557 | International Design Codes Manual — 651 .0 0.00 FYLD= 235.021 FakY=1.00 FYLD= 235.701E+2 KNM | | IR1 = 0.3. N/MM2 | | Betamz=1.2 36.500 | | MYD =.9 -36.000 FakZ=1.2 STAB 10.076 VON MISES = 3.033 | | MYD =.2) kN-m kN-m kN-m IR2 VON MISES Interaction ratio for von Mises NS3472 (VERSION 06002) UNITS ARE KN AND METE MEMB FX MYs MYm MYe MYb RATIO LOAD TABLE MZs MZm MZe MZb COND DIST =============================================================================== 1 12. 12.4.000 FakZ=1.9 STAB 5.4.701E+2 KNM MZD =.08 1 FAIL PIPS40 (AISC SECTIONS) 31.295 Betamy=1.575 VON MISES = 0.00 Beta Y 1.00 |-------------------------------------------------------------------------| | CURVE St A Wk A Beta Z 1.58 1 PIPD60 (AISC SECTIONS) 36. 12.076 IR2 = 5.3.575 IR2 = 0.80 C 0.112E+2 KNM | | IR1 = 5.Symbol CURVE Wk Beta Z Beta Y FYLD Betamz Betamy Fak Z Fak Y MYD MZD MVD IR1 Description Buckling curve about the weak axis Buckling length factor about z-axis Buckling length factor about y-axis Allowable yield strength Equivalent moment factor β Equivalent moment factor β m m Unit N/mm 2 about z-axis about y-axis Factor k according to 12.0 5.0 0.112E+2 KNM MZD =.4.00 Beta Y 1.377 Betamy=1.2 about the z-axis Factor k according to 12.02 C 0.0 0.2) Interaction ratio for buckling with lateral buckling (Cl.4.701E+2 KNM MVD =. N/MM2 | | Betamz=1.0 0.4 -38.3.9 -15.83 |-------------------------------------------------------------------------| | CURVE St A Wk A Beta Z 1.0 0.1 -6.0 0.8 38. 000 FakZ=1.500 | | MYD =.00 FYLD= 235.9 STAB 14.112E+2 KNM MVD =.4 -2.00 Beta Y 1.304 IR2 = 1.0 0.510 Betamy=1.0 0.784 IR2 = 0.9 2.0 0.304 VON MISES = 0.2 -1.500 FakY=1. N/MM2 | | Betamz=1.500 | | MYD =.20 C 0.0 0.152 Betamy=1.112E+2 KNM MZD =.310 | |-------------------------------------------------------------------------| 652 — STAAD. N/MM2 | | Betamz=2.78 1 PIPS40 (AISC SECTIONS) 5.0 0.112E+2 KNM | | IR1 = 1.Steel Design per NS 3472 / NPD |-------------------------------------------------------------------------| 3 26.Pro .602 FakY=1.14A.1 1.14 |-------------------------------------------------------------------------| | CURVE St A Wk A Beta Z 1.3 2.00 |-------------------------------------------------------------------------| | CURVE St A Wk A Beta Z 1.000 FakZ=0.112E+2 KNM | | IR1 = 0.0 1.0 0.112E+2 KNM MZD =.510 | |-------------------------------------------------------------------------| 4 24.00 Beta Y 1.31 C 0.0 0.00 FYLD= 235.30 1 FAIL PIPS40 (AISC SECTIONS) -0.784 VON MISES = 0.5 5.1 STAB 0. Norwegian Codes .112E+2 KNM MVD =. Output example for TRACK 2.0 International Design Codes Manual — 653 . Pro .0 Member in tension: 654 — STAAD. Norwegian Codes .Steel Design per NS 3472 / NPD Output example for TRACK 3 Output example for TRACK 9.14A. Member in compression: International Design Codes Manual — 655 . Norwegian Codes .Steel Design per NS 3472 / NPD 656 — STAAD.Pro .14A. Member in compression (pipe .NPD): International Design Codes Manual — 657 . Pro .14A.Steel Design per NS 3472 / NPD 658 — STAAD. Norwegian Codes . 0 International Design Codes Manual — 659 .8.14A.2 Tracks for joint capacity code checking Output example for TRACK 99. Norwegian Codes .Pro .0 660 — STAAD.14A.Steel Design per NS 3472 / NPD Output example for TRACK 98. 8.14A.3 Special prints (not code check) Output example for TRACK 49 Output example for TRACK 31 International Design Codes Manual — 661 . Norwegian Codes .14A.Pro .Steel Design per NS 3472 / NPD Output example for TRACK 32 662 — STAAD. this STAAD.Pro performs design checks.1. N-004 does not specify steel grades to be used.3 Ultimate Limit States Clause 6.1. 6 & 7 in of that document. 14B. 14B. The choice of design class (as per Table 5-1 of the code) is left to you and does not have any direct impact on how STAAD. Eurozone Design Codes SELECT Code Pack.Pro considers sections 4.1.Steel Design per NORSOK N-004 STAAD. N-004 does not explicitly specify how to classify various cross sections.14B. Also.5 of EN 1993-1-1:2005.Pro is capable of performing steel design based on the Norwegian code NORSOK N004 Rev 2. 14B. 5.Pro uses the steel grades per EN 1993-1-1:2005 for designs per N-004. Design of members per NTC 1987 requires the STAAD N. Therefore. except when specified explicitly along with member checks (See Member Subject to Axial Compression). The choice of design class will determine the choice of steel grade & quality and also the determination of inspection category for fatigue. The details of the various clauses implemented from these sections is presented here for member checking and design. Norwegian Codes . The material factors chosen are dependent on the ‘section class’ of a cross section. International Design Codes Manual — 663 .1 primarily deals with the section of material factors to be used in the various conditions or checks. Please note the following: l l The code check is available for the pipe cross sections only. October 2004. the section classification is made as given in Section 5.1 General Provisions The general safety check is per Section 4. 14B. The design of conical transitions and joints with joint cans is not performed.1 Member Resistances The implementation of the NORSOK N-004 code in STAAD. Therefore. Checks are made to ensure that the design action effect (S ) is less than or equal to the design resistance (R ): d d Sd ≤ Rd The design resistance is evaluated for each condition and this check is applied as described in the following sections. Code checks for tubular (pipe) members is performed per the code.2 Steel selection and non destructive testing Section 5 deals with the choice of “design class” for structural joints and components. Also. if so.Steel Design per NORSOK N-004 Note: Ring stiffener design to CL. to specify the hydrostatic pressure for the element.6. Warning: Only tubular sections can be used with the N-004 code in STAAD. a warning will be issued by the engine and the design of that member is aborted.8 of the code.4 Tubular Members Clause 6. By default the program will assume that all members are not subject to any hydrostatic pressure. l l The yield strength for tubular member ≤ 500 N/mm 2. the program will assume that the hydrostatic loads have not been included in the analysis. The program allows you to specify whether a member is subject to hydrostatic pressure or not and.Pro convention for the Z and Y axes. the design will be done according to Clause 6. 664 — STAAD.2 is not included for this implementation. where ‘Z’ defines the in plane effects and ‘Y’ the out of plane effects.3. bending plus compression) along with a hydrostatic pressure.9 of the code. Norwegian Codes . 6.Pro .1 deals with the general considerations while using tubular members. In the absence of any hydrostatic pressure on the member the design will be performed in accordance with Clause 6. Note: N-004 uses ‘Y’ to define the action effects that is in plane and ‘Z’ to define out of plane effects.8 KN/m 3). The slenderness ratio of the cross section D/t < 120. the program will take that to be the water level and will evaluate the pressure distribution on each element assuming a linear increase in pressure with depth (The density of water is assumed to be 9. If the HYD parameter is specified.Pro. The design parameter HYD is used to specify the maximum water level with respect to the origin. A warning is presented for any other section type. Where D is the diameter and t is the wall thickness of the section. If any of these conditions are not met for a member selected for design.14B. 14B.. The N-004 code also segregates members into those that are subject to hydrostatic pressure and those that are not subject to hydrostatic pressure.1. This document will follow the STAAD.e. The dimensions of the tubular sections are limited as follows: l l The thickness t ≥ 6 mm. if the HYD parameter is specified. The thickness t <150 mm.3. For members that are subject to a combination of loads (i.3. This is the opposite to what STAAD uses.3. 3.15 14B.3.34 y λ = √(f /f ) = k l/(π i)√(f /E) cl E cl Where: f = Characteristic local buckling strength cl λ = Column slenderness parameter f = Smaller Euler buckling strength in y or z direction.3 Axial Tension Clause 6.Rd = A f /γ y m = Design axial force (tension positive) f = Characteristic yield strength A = Cross section area γ m = Default material factor = 1.Rd = A f /γ c m = Design axial force (compression positive) f = Characteristic axial compressive strength γ m = Refer to clause 6.7 The design axial compressive strength for a member that is not subject to any hydrostatic pressure will be taken as the smaller of in plane or out of plane buckling strengths determined by the equations given below: f = [1.2 states that tubular members subject to axial tension shall satisfy the following condition: N Where: N y Sd Sd ≤N t.34 c c y f = 0.2 .1 Ultimate Limit State 14B.028 λ2]f when λ ≤ 1. refer to Clause 6.1x105 MPa k = Effective length factor.0 .3.14B.8.9/λ2 f when λ > 1.3 states that tubular members subject to axial compression shall satisfy the following condition: N Where: N c Sd Sd ≤N c.3.4 Axial Compression Clause 6.2 l = Longer unbraced length in y or z direction International Design Codes Manual — 665 . E E = Young's modulus of elasticity = 2. 170 < f /f f =f Where: f cle e cle ≤ 1.5 Bending Clause 6.14B.047 .0517 < f D/(E t) ≤ 0.6 Shear Clause 6. The characteristic local buckling strength is determined from: f = f when f /f cl cl cl y y cle ≤ 0.22 (Cl.3 (Critical elastic buckling coefficient) D = Outside diameter t = wall thickness For a member that is subject to pure compression.7) of the code.1034 < f D/(E t) ≤ 120 f /E y y y y 14B. if f /f > 0.3.Pro . In such cases.3.911 (Elastic buckling) = 2C E t/D (Characteristic elastic local buckling strength) e C = 0.5 states that tubular members subject to shear shall satisfy: V Where: V Sd Sd ≤V Rd = A f /(2√3 γ y m) ) = Design shear force 666 — STAAD.911 (Elastic/Plastic) when f /f y cle > 1. 6. Norwegian Codes .4 states that tubular members subject to pure bending alone shall satisfy: M Where: M f Sd Sd ≤M Rd =f m W/γ m = Design bending moment m = Characteristic bending strength W = Elastic section modulus γ m = Refer to clause 6.170 (Plastic yielding) y cle y y cle f = [1. 14B.7 m The bending strength f f f f m m m y is calculated as: y = Z/W f when f D/(E t) ≤ 0.3.58 f D/(E t)] Z/W f when 0.13 .170.0.0.0517 = [1.Steel Design per NORSOK N-004 i = Radius of gyration. the value of the material factor (γ ) used in the m above checks is increased according to equation 6. the section will be classed y cle as a CLASS 4 (slender section).76 f D/(E t)] Z/W f when 0.3.94 .1034 y y y = [0.274 f /f ] f when 0.2. 3.44 f y y he f = 0.f = Yield strength y A = Cross section area γ m = Default material factor = 1.44 t/D + 0.5 μ = Geometric Parameter = L/D√(2 D/t) International Design Codes Manual — 667 .55 f y ≤ 0.0.Rd = f /γ h m) =p Sd D/(2 t) p = Design hydrostatic pressure f = Characteristic hoop buckling strength h γ m) = Refer to clause 6.6 D/t C = 0. the following condition shall also be satisfied: M Where: M p T.825 D/t C = 0.15 When torsional shear stresses are present.Rd = 2 I f /(D√3 γ py m) ) = Design bending moment I = Polar moment of inertia 14B.21 (D/t)3/μ4 when 0.8 when μ <1.Sd Sd p.6 D/t h h h h C = 0.7 f =f he f (f /f )0.7 h The characteristic hoop buckling strength f .6 states that tubular members subject to an external pressure shall primarily be checked for hoop buckling.Sd T.3.737/(μ .44 t/D when μ ≥1.Sd ≤f h. The condition to be satisfied is: σ Where: σ p.7 Hydrostatic Pressure Clause 6.579) when 1.Sd ≤M T.44 f ≥ f y he > 0.5 ≤ μ < 0.4 y he y when f he when 2.55 f The elastic hoop buckling strength f f Where: he will be worked out as follows: = 2C E t/D h C = 0. will be calculated as follows: f = f when f h h h y he > 2.825 D/t ≤ μ <1. Sd is the design bending moment about the y axis (out-of plane axis) is the design bending moment about the z axis (in plane axis) Sd Rd is the design axial force is the moment resistance (as determined by Clause 6.8.2) M N t.85 for both). 14B. respectively (default is 0.1 states that tubular members subject to axial tension and bending shall be designed to satisfy the following condition: Where: M M N y.Pro .Sd z.Rd 14B.3. diaphragms. Norwegian Codes . or end connections.3.9 Combined Axial Compression and Bending (without Hydrostatic Pressure) Clause 6.Steel Design per NORSOK N-004 L = Length of tubular member between stiffening rings.2 states that tubular members subject to axial tension and bending shall be designed to satisfy the following conditions: and Where: N Sd is the design axial compression C and C are the reduction factors corresponding to the Y and Z axes my mz respectively. You may specify a value for these using the CMY and CMZ design parameters.8.8 Combined Axial Tension and Bending (without Hydrostatic Pressure) Clause 6.3.4) is the tension capacity of the section (as determined by Clause 6.14B. N ey and N ez are the Euler buckling loads about y & z axes and are given by: 668 — STAAD.3. This requires the member to be classified under any one of the section types given in the table.3(τ T.7 International Design Codes Manual — 669 .10 Combined Bending and Shear (without Hydrostatic Pressure) Clauses 6.V /V ) when V /V ≥ 0.Sd /f )2] τ =M y m /(2π f = f /γ d R = Radius of the tubular member γ m = Refer to clause 6.Rd ≤ √(1.3.4 .4 Sd Rd Red.4 state that tubular members subject to beam shear force (excluding shear due to torsion) and bending moments shall satisfy: M /M Sd Sd Rd Rd ≤ √(1.3 & 6.4 .Rd Red.V /V ) when V /V ≥ 0.0 when V /V < 0. the condition to be satisfied is: M /M Sd Sd Red.4 Sd Rd Sd Rd M /M ≤ 1.Sd = f √[1 .3. N cl. 14B.8.0 when V /V < 0.Red m T.Sd d R2 t) /γ m.4 Sd Rd If the member is subject to shear forces due to torsion along with bending moments.8.3) cl The reduction factors used in this clause depend on the ‘structural element type’ and will be as given in Table 6-2 of N-004.3.Red T.Rd =W f m m.k is the effective length factor and is given in table 6-2 of the code.4 Sd Rd Sd Rd M /M Where: M f ≤ 1. Rd is the design axial local buckling resistance given by: f is the characteristic local buckling strength (as determined by Clause 6.3. 09 B2 .3.3B] m mh. then Method B in the code is used. For the net axial tension condition (σ a.B2η) .Sd is the out of plane bending stress is the in plane bending stress y m m th. the section is verified for hoop stress limit per clause 6.Pro will depend on the HYD parameter specified as a design parameter.Rd 670 — STAAD. When HYD is specified: The following condition is to be satisfied: a. (i. If. Bending.RD = f /γ [√(1 + 0. Method A given in the code is used.Pro . on the other hand.11 Combined Loads with Hydrostatic Pressure Clause 6.12 Combined Axial Tension. σ is the design axial compressive stress due to hydrostatic q.Sd ) Where: σ is the design axial stress. If. σ σ f f my.RD B=σ psd /f h. If the HYD parameter has been specified.09 B2 .3B] = f /γ [√(1 + 0.9 of NS-004 describes two methods to check for members subject to combined forces in the presence of hydrostatic pressure: depending on whether the hydrostatic forces were included as nodal forces in the analysis or not.3.Sd pressure.3. the HYD parameter has not been specified.Sd from hydrostatic pressure. the axial load arising from the hydrostatic pressure being applied as nodal loads).Sd ≥σ q.Steel Design per NORSOK N-004 14B. the hydrostatic forces have been included in the analysis. Prior to proceeding with the checks described in the sections below.1: A. If the hydrostatic forces have not been included in the analysis as nodal forces. the program will use the section forces and use Method B in the code. however. then the program will assume that the hydrostatic forces have not been included in the analysis and will perform the necessary checks as per Method A in code..6 (see Hydrostatic Pressure above).14B.0. 14B.e.9.B2η) .Sd mz. Norwegian Codes .0. and Hydrostatic Pressure Checks per Clause 6. excluding any axial compression a. The choice of method for checking members subject to combined forces and hydrostatic pressure used by STAAD. 9.2: A.13 Combined Axial Compression.Sd > 0. and Hydrostatic Pressure Checks per Clause 6. when: σ c.3. For the net axial compression condition (σ <σ q.Sd is the axial stress in the member 14B.Sd b.Sd ) Where: f cl.5 f he the following condition shall be satisfied in addition to the above check(s): Where: σ c.Sd is the maximum compressive stress at that section.Rd = f /γ cl m f is the characteristic local buckling strength (as determined by cl Clause 6.3.4 f /f h y a.3) Additionally.η = 5 . Method used when HYD has been specified: The following condition is to be satisfied: International Design Codes Manual — 671 .5 f /γ he m and f cle > 0. When HYD has not been specified: Where: σ ac. B. Bending. Sd pressure Additionally. Method used when HYD has not been specified: The following condition is to be satisfied: 672 — STAAD.14B.5 f /γ he m and f cle > 0.Sd > 0.Steel Design per NORSOK N-004 and Where: σ is the design axial stress that excludes the stress from hydrostatic a. Norwegian Codes . when: σ c.5 f he the following condition shall be satisfied in addition to the above check(s): B.Pro . Sd ≥σ q. b. They are set to default values to begin with and may be altered to suite the particular structure.Sd is the maximum compressive stress at that section.Sd ) (Refer to the previous section for an explanation of these terms).14 Design Parameters Design parameters communicate specific design decisions to the program.Sd > 0.5 f /γ he m and f /γ cle m > 0. 14B.a. when: σ c. For the net axial tension condition (σ ac.Sd <σ q.Sd ) and (Refer to the previous section for an explanation of these terms). International Design Codes Manual — 673 .5 f /γ he m the following condition shall be satisfied in addition to the above check(s): Where: σ c. For the net axial compression condition (σ ac. Additionally. 85 LZ CMY CMZ 0.0 LY Member Length Member Length 0.Pro . Length in local Y axis for slenderness value KL/r Length in local Z axis for slenderness value KL/r Reduction factor C corresponding to the Y m axis. in local Z-axis.1-Design Parameters for NORSOK N-004 design code Parameter Name CODE Default Value none Description Must be specified as NORSOK. FYLD 235 [MPa] Yield strength of steel. usually major axis.85 LSR 674 — STAAD.1. in local Y-axis. Reduction factor C corresponding to the Z m axis.0 Effective length factor. f (St37) y Note: Note. Note: Do not use the shortened NOR. if the SGR value is specified. usually minor axis.Steel Design per NORSOK N-004 Table 14B. then the associated value of f for y that steel grade will be used for a member in lieu of the FYLD value.3. KZ 1. Length of Tubular between Stiffening Rings. Effective length factor. KY 1. Norwegian Codes . This value is required to calculate Design Hoop Stress due to Hydrostatic Pressure to check Hoop Buckling as per clause 6. k.14B.6. as this initiates an NS3472 design . k. Steel Grade per EC3 (EN 1993-1-1:2005): 0.0 Description The Y-coordinate. then yi will be the Z coordinate of the max water level. 0.0 output. International Design Codes Manual — 675 . For HYD > 0. Minimum allowable depth of steel section.0 = Check for slenderness 1.0 = S 460 grade steel DMAX DMIN DFF 100. the value of max.0 Water pressure at each section in absence of HYD.0 MAIN Option to design for slenderness. "Deflection length"/maximum allowable local deflection. hydrostatic pressure calculated is reported for each member in a TRACK 2.0 is used as the limit for slenderness in compression.0 = S 275 grade steel 2.0 = S 355 grade steel 3. SGR 0.0 [cm] 0. PSD 0. current units. Note: If SET Z UP command has been specified.0 = S 235 grade steel 1. of the maximum water level with respect to the origin.0 = Do not check for slenderness Any value greater than 1.0 = S 420 grade steel 4.0 Maximum allowable depth of steel section.Parameter Name HYD Default Value 0.0 [cm] None (Mandatory for deflection check) 0. 0 = All the details of the member checks and the various clause checks performed are printed.1 Notes a.0 Permissible ratio of the actual to allowable stresses.0 = Perform design for moments at twelfth points along the beam.14B. TRACK 0.0 = design only for end moments and those at locations specified by SECTION command.0 DJ1 Start Joint of member End Joint of member Joint No. BEAM 0.2-Default values for C1 and C2 parameters Joint Type T or Y joints under brace axial load X joints under brace axial load C1 25 20 C2 11 22 676 — STAAD. Output detail: 0. denoting end point for calculation of “deflection length” DJ2 14B.14. 1. 2. Slenderness limit is checked based the MAIN parameter.Steel Design per NORSOK N-004 Parameter Name TMAIN Default Value 180. C1 and C2 Parameters The default values of these coefficients are taken from Table 6-4 of N-004 and depend on the joint and load type: Table 14B.Pro . Beam segment locations for design: 0.0 = Only a summary of the design checks performed is printed. Norwegian Codes . denoting start point for calculation of “deflection length” Joint No.0 RATIO 1.0 Description Slenderness limit in tension. If no sections are specified.15 Code Checking The purpose of code checking is to ascertain whether the provided section properties of the members are adequate as per N-004..0 MEMB 1 TO 3 PSD 10 MEMB 7 10 SGR 2 MEMB 1 TO 3 7 10 TRACK 2 MEMB 1 TO 3 7 10 CHECK CODE MEMB 1 TO 3 7 10 14B. the critical condition of NORSOK code.2 Example Note: This is a partial example containing only the information pertaining to the NORSOK N-004 steel design code. the program calculates and prints whether the members have passed or failed the checks. the governing load case. X. International Design Codes Manual — 677 . the program uses the start and end forces for code checking. and Y values in the external geometry file.16 Member Selection STAAD is capable of performing design operations on specified members. and the location (distance from the start of the number of forces in the member) where the critical condition occurs.e. Once an analysis has been performed. 14B. Code checking is done using the forces and moments at specific sections of the members. When code checking is selected.14. the value of the ratio of the critical condition (overstressed for value more than 1. the program can select the most economical section (i. The section selected will be of the same type section as originally designated for the member being designed.0 or any other specified RATIO value). the lightest section which fulfills the code requirements for the specified member). Member selection can also be constrained by the parameters DMAX and DMIN which limit the maximum and minimum depth of the members. * CHECK TUBULAR MEMBERS ACCORDING NORSOK N-004 CODE NORSOK HYD 3. 14B.Joint Type K joints under balanced axial load All joints under brace moment loading C1 20 25 C2 22 30 Note: These values can be changed by setting the K. used at the end of the input file. Joint classification is the process whereby a BRACE member connecting into a CHORD member is classified into one of these categories based on the axial force components in the brace.14B. the joint should be classified into one of the three categories given by the code. The code allows a 10% tolerance in the balancing force. Joint Classification K Description The axial force in the brace should be balanced by forces in the other braces in the same plane and on the same side of the joint. The axial force in the brace is reacted as a beam shear in the chord. N-004 defines three joint classification categories: K.4 of N-004 and will be applicable to joints formed from a connection of two or more members.Pro .1 .Steel Design per NORSOK N-004 Selection of members whose properties are originally input from a user created table will be limited to sections in the user table. X. The axial force in the brace is carried through the chord to braces in the opposite side. 14B. Norwegian Codes .Typical Tubular Joint (Fig 6-1 in N004) Prior to completing a joint design. Figure 14B. or Y (or a combination of these).17 Tubular Joint Checking The design of tubular joints for this implementation shall be based on section 6. X Y 678 — STAAD. The classification normally considers all the members at a joint that lie in a plane. All joints will initially be classified as Y in the generation of the external geometry file. For each node specified in the CHECK JOINT command. Note: STAAD. The angle between the two members should be within the range of 30° and 90° (inclusive). It is worth noting that the joint class for each brace will be different for each load case. 6. However. The input variables used for the initial joint checks will be generated in an external text file.4.4. You can then use this text file to edit or modify the input variables and perform a final check as necessary. The code also specifies checks and limits for the gaps and eccentricity of joints.1 Identification and Classification of CHORD and BRACE Members This is a two step process where the program automatically identifies the CHORD and BRACE members at a joint and perform a default joint check. This is left up to the engineer.17. The program the automatically creates the joints and initially considers all the joints as joint class Y.Pro performs the checks as per these clauses. This implementation will not perform such geometry checks.6 and STAAD.3.Pro does not perform an automatic classification of the joints. The program then performs all the International Design Codes Manual — 679 .3. The checks for joint capacity are given in Cl. Joints should be re-classified as necessary before performing the final joint capacity checks. The following syntax is used to initiate the joint checking in the engine. the program automatically separates out all the members at the node into one CHORD member and one or more BRACE members. 14B. the program considers every CHORD to BRACE connection as a separate JOINT. LOAD LIST load_list PARAMETER 1 CHECK JOINT { node_list | ALL } Where: load_list = a list of load case numbers to be check against node_list = the NODE numbers to be checked. If two or more possible CHORD members have the same diameter. The details of the checks done and the methodology will be discussed in the following sections. Once all the CHORD and BRACE members are identified.Note: Typical examples of these joint types are given in Figure 6-3 of the N-004 code. the program does not deal with conical joint transitions and joints with joint cans. Specifying the ALL keyword option will cause the program to perform the joint check at all the nodes. The section with the biggest diameter is assumed to be the CHORD and all the other members are assumed as BRACE members.2 to 6. the member with the maximum thickness is considered as the CHORD. 3 of N-004 for these equations.15 θ is the angle between the chord and the brace (max θ = 90 degrees) Q = Strength factor which varies with the joint type and the action type in the u brace.14B.3. M y f is the yield strength γ m = Default material resistance =1.Sd mz. it is assumed that you have already done a joint design check and hence the program reads the values from this file and uses these for joint checks. Note: This file will be produced only once (i.Sd is the design axial stress in the chord is the design in-plane bending stress in the chord is the design out-of-plane bending stress in the chord my.Sd + C 2 2 f 1.Steel Design per NORSOK N-004 necessary joint checks as detailed in the following sections and produces the design output.STD file. when this file does not exist).e.18 Tubular Joint Resistance 14B. it will read in the necessary parameters from this file and perform the subsequent design checks. The program will also produce an output file called filename_ JOINTS.txt. If this file exists.Pro . Once the program finds of the _JOINTS. Norwegian Codes .1 Basic Joint Resistances The characteristic joint resistance between a chord and a brace is given by: NRd = MRd = f yT 2 γ M sin θ f y T 2d γ Msin θ Q uQ f Q uQ f Where: N Rd Rd is the joint design axial resistance is the joint design bending moment resistance. 14B. You can then edit this text file to set up the necessary design parameters. This format of this text file is explained in Section 14B.Sd 680 — STAAD..62f y y σ σ σ p.Sd A 2 = C1 a .18.8.4. Q = 1.txt file. Refer to Table 6-3 and Clause 6.0 – λA2 f 2 2 2 σ my σ .Sd + σ mz. where "filename" will be the name of the . is the joint design axial resistance is the in plane bending moment in the brace is the out of plane bending moment in the brace is the in plane bending moment resistance is the out of plane bending moment resistance M M M M z. X%.NGo file should meet the following format. 14B.. C2 is the coefficient used for the bending stress term in calculating the joint resistance.1 General Format LOAD LIST load_list JOINT NODE K X Y CHORD CLEN D T BRACE BLEN d t GAP j# n# K% X% Y% C# CLEN D T B# BLEN d t gap Where: j# = the joint number n# = the node number K%. The default values of C1 and C2 are as given in Table 6-4 of N-004.19 External Geometry File The data contained in the filename_JOINTS. K=0. The actual values used are dependent on the values of K.Sd y. and Y specified for the joint in the external geometry file. respectively.2 Strength Check for Joints Each brace to chord joint to be checked will have to satisfy the following condition: N Sd N Rd 2 M + z.Sd z.Rd 14B.C1 is the coefficient used for the axial stress term in calculating the joint resistance.Sd + M z. X.7.Rd ≤1 Where: N N Sd Rd is the design axial force in the brace. See also Figures 6-3 to 6-6 of N-004 for definition of the various terms for various joint classes. X=0 and Y=1).Rd y.19.Sd M y .Rd M y . The overall process of performing punching shear checks consists of two steps which are explained in Section 14B.18. 14B.e. Initially the joints will be classed as Y (i. C# = the member numbers of the CHORD International Design Codes Manual — 681 . and Y% = The fractional contributions of K-type. X type and Y-type. 075 0.14B. MY and MZ are printed since they are the ones which are of interest. The items in the output table are explained as follows: Member the member number for which the design is performed. CRITICAL COND the section of the N-004 code which governs the design.04 14B. T = Diameter and thickness of CHORD B# = the member number of the brace BLEN = the length of chord member d. the value of GAP is assumed as 0.10 0. MY. 682 — STAAD. and MZ provide the axial force.168 0.19.10 BRACE 1 16 4.005 K T 0 0 0 0 X GAP 0 0 Y 1 1 CHORD 2 2 CLEN 5. LOADING the load case number which governed the design.0 or less will mean the member has passed.0 6. RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition.168 T 0. there will be an asterisk (*) mark on front of the member. 14B.2 Example LOAD LIST 1 2 4 JOINT NODE BLEN D 1 3 0.0 D 0. TABLE the steel section name which has been checked against the N-004 code or has been selected. RESULTS prints whether the member has PASSed or FAILed. the program produces the results in a tabulated fashion. FX.Pro .010 2 3 0.0 5. in most cases. moment in local Y-axis. Normally a value of 1. Initially. only FX.140 0. If the RESULT is FAIL. and the moment in local Z-axis respectively. Norwegian Codes .Steel Design per NORSOK N-004 CLEN = the length of chord member D. Although STAAD does consider all the member forces and moments (except torsion) to perform design.20 Tabulated Results For code checking or member selection. t = Diameter and thickness of BRACE gap = Distance required to calculate gap factor for K bracing. 554 123.70 z-axis 862.000 y-axis 862.1 52.00 ======================================================================= MATERIAL DATA Grade of steel = S 355 Modulus of elasticity = 204999.000 Moment of inertia Plastic modulus Elastic modulus Radius of gyration Effective Length DESIGN PARAMETER (units Height of water lavel CMZ : 0. Note: If the parameter TRACK is set to 2. 14B.000 168.m) N004/2004 : 3.00 KY SECTION CLASSIFICATION : : : : : . allowable axial stress in compression (FA).407 4.602 400.4 790.NORSOK-N004 (V1.00 : Class 1 CAPACITIES (units .602 400.20.PRO CODE CHECKING .m) Tension Capacity Compression Capacity Bending Capacity Shear Capacity : : : : 1256.39 0.00 Gross Area of cross section = 40.407 4.000 : 0.01 C 1.000 168.0 Output STAAD.85 CMY KZ : 1. the program will block out part of the table and will print the allowable bending stressed in compression (FCY & FCZ) and tension (FTY & FTZ).85 : 1. and allowable shear stress (FV).01 6.554 123.0 362.44 0.cm) Member Length = 400.00 N/mm2 SECTION PROPERTIES (units . 6.0.1 Sample TRACK 2.kN.LOCATION specifies the actual distance from the start of the member to the section where design forces govern.0 (BRITISH SECTIONS) PASS Eq.98 N/mm2 Design Strength (py) =355.7 International Design Codes Manual — 683 .170 1 0.KN MEMBER TABLE METE (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST PIP13910.0) ************************************************ ALL UNITS ARE . Pro .N.8.4 0.8.4 1.0 Cl:6.0 HYDROSTATIC PRESSURE CALCULATION (units .3.000 Max design hoop stress.0 Cl:6.000 1 0.0 ======================================================================= 684 — STAAD.3.5 0.170 1 0.3.Cl.3.3.(3 & 4) 0. (sigma_psd)) : 0.3.5 Cl:6.9 0. Norwegian Codes .0 Cl:6.(1 & 2) 0. (psd) : 0.6 Max design hydrostatic pressure.Steel Design per NORSOK N-004 Shear Capacity due to torsional moment: 44.102 1 -5.3.4 1.14B.124 1 0.5 -5.0 Cl:6.3.3 0.6.2 0.031 1 -11.2 0.0 6.102 1 -0.mm) .0 Cl:6.kN.3 0.0 6.3 0.5 0.000 1 0.m): CLAUSE RATIO LOAD FX VY VZ MZ MY Cl:6.000 CRITICAL LOAD FOR EACH CLAUSE CHECK (units . Pro is capable of performing concrete design based on the Norwegian code NS 3473 2001 Concrete Structures . 3. Design of members per NS 3473 requires the STAAD N. Beam/ Column braced in both directions. Column Brace Parameter 0.1 Design Parameters Design parameters communicate specific design decisions to the program. Table 14C. Column unbraced about the local y axis only. in percent. in years. Drying exposure.2 of the Technical Reference Manual. Eurozone Design Codes SELECT Code Pack. Distance from the end node of the beam to face of support for shear design. Column unbraced in both directions. Norwegian Codes . 1. 2. They are set to default values to begin with and may be altered to suite the particular structure. 14C. Member length factor about the local z direction ELY ELZ 1 1 International Design Codes Manual — 685 .1-Design Parameters for NS 3473 design code Parameter Default Name Value CODE none Description Must be specified as NS3473 Design Code to follow.14C. ACTAGE BRACE 70 years 0 Enter the actual age. One-way plate/ Column unbraced about the local z axis only.52. CLEAR DRYCIR EFACE 25 mm 100% 0 Clear cover to outermost reinforcing bar.Design and detailing rules. Member length factor about the local y direction. See section 5.Concrete Design per NS 3473 STAAD. Faced symmetric distribution SFACE 0 Distance from the start node of the beam to face of support for shear design. Two faced distribution about minor axis. Two faced distribution about major axis. STIRANG STIRDIA TORANG 90 10 mm 45 686 — STAAD. in days. Stirrup diameter Torsion angle. 2. in percent. Relative humidity. LA — Least aggressive 2. in degrees. Column bar arrangement 1. Minimum size permitted for main reinforcement bar. Maximum size permitted for main reinforcement bar.Concrete Design per NS 3473 Parameter Default Name Value ENVIR 2 Environment class Description 1. LAGE MAX MAIN MINMAIN Age when loaded. moy factor moz factor nmag factor 10 MOY MOZ NMAG REIANG RELHUM RFACE 0 70% 1 Reinforcement angle.14C. Norwegian Codes .Pro . in degrees. in degrees. 3. MA — Very aggressive FC 35 N/mm 2 500 N/mm 2 7 days 32 Compressive strength of concrete. Four longitudinal bars. Stirrup angle. 4. NA — Aggressive 3. FYMAIN Yield strength of main reinforcing steel. Parameter Default Name Value TRACK 10 Description Track parameter to control output detail 10. Slab — Plane stress design. 30. 12. International Design Codes Manual — 687 . Beam — Ultimate limit state and Service limit state design & Slab — Two-way plate design 11. Slab — Simplified membrane design. Beam — Ultimate limit state and Service limit state design with tension stiffening. Beam — Ultimate limit state design only 20. 688 — STAAD.Pro . Section 15 Russian Codes International Design Codes Manual — 689 . 690 — STAAD.Pro . shells) members are incorporated in program STAAD. Ratio between design and normative loads is called reliability coefficient for loads which is determined according to SNiP 2.01. Design of members per SNiP 2. Code SNiP 2. Not only Code SNiP 2. Analysis of structures for the second group of limit states is made in accordance with the operational (normative) loads and actions.-85 “Loads and actions”.01-84* STAAD. loss by structure of stable form or position.03.03. plastic or other type of failure.03.1 General Russian Code SNiP 2.07.0184*: СТРОИТЕЛЬНЫЕ НОРМЫ И ПРАВИЛА БЕТОННЫЕ И ЖЕЛЕЗОБЕТОННЫЕ КОНСТРУКЦИИ (SNiP 2.Concrete Design Per SNiP 2. International Design Codes Manual — 691 .01–84* defines two groups of limit states. fatigue failure.03.01-84* Building Regulations: Concrete and Reinforced Concrete Construction).07. Program STAAD.15A. Eurozone Design Codes SELECT Code Pack. columns) and 2D (two dimensional) (slabs. Reliability coefficient γn for destination according to SNiP 2.01–84* plain concrete and concrete structures is based on the method of limit states.03.01-84)” have been used in creation of these algorithms. Russian Codes .01-84* requires the STAAD E.Pro is capable of performing concrete design based on the Russian code СНиП 2.03. l Analysis of structures for the first group of limit states is performed with the use of the maximum (design) loads and actions. 15A. failure due to the action of load actions and unfavorable environmental effects. Analysis according to the first group of limit states is performed to avoid the following phenomena: l brittle.-85 shall be considered in determination of loads and their combinations. excessive displacements.03.03. l l l Analysis according to the second group of limit states is performed to avoid the following phenomena: l excessive and long-term opening of cracks if they are allowed according to service conditions.01-84* but also the “Guide for design of plain concrete and reinforced concrete structures from normal weight and lightweight concrete (to SNiP 2. walls.Pro makes it possible to calculate reinforcement for concrete members according to codes of many countries round the World and Russian Code SNiP 2.01.01-84* inclusive.Pro. Algorithms for calculation of reinforcement of concrete linear (beams.03. 15A. Russian Codes .Pro . * BEAMS OF T CROSS-SECTION 23 TO 40 PRI YD 450. and thicknesses of 2D members are entered by ELEMENT PROPERTY command.15A.Notation of dimensions for rectangular. Example: UNIT MM MEMBER PROPERTIES * COLUMNS OF RECTANGULAR CROSS-SECTION 1 TO 16 PRI YD 350. AFTER OUTPUT COMMANDS TO PRINT RESULTS OF CALCULATION. YB 230.2 Design Parameters and Input Data Entry of data of cross-sections of beams and columns is made by the use of MEMBER PROPERTIES command. UNIT METER ELEMENT PROPERTY 41 TO 100 THICKNESS 0. ZB 200. * COLUMNS OF CIRCULAR CROSS-SECTION 17 TO 22 PRI YD 350.Pro to calculate reinforcement for beams of rectangular or T section and for columns of rectangular or circular section (Fig.01-84* It is possible using program STAAD. if BETA=180°. circular and T sections Flange of T-shape beams may be situated at the top zone of the section if the angle BETA=0°.03. Figure 15A. MEMB 23 TO 40 COMMANDS FOR CALCULATION OF REINFORCEMENT ARE LOCATED IN THE INPUT DATA FILE AFTER THE COMMAND OF ANALYSIS AND AS A RULE.Concrete Design Per SNiP 2.1 .1).14 101 TO 252 THICKNESS 0. ZD 550. or at the bottom zone of the section. ZD 350. Example: * COMMAND OF ANALYSIS 692 — STAAD.16 * FLANGE OF T BEAMS IS LOCATED AT THE BOTTOM ZONE OF CROSSSECTION BETA 180. Note: Once a parameter is specified. This is the way STAAD works for all codes. MEMB 17 TO 22 CL1 0. the values of which differ from determined in the program. In the file of input data only such parameters have to be taken.* LIST OF PARAMETERS BEING USED IN REINFORCEMENT CALCULATION . Values of parameters do not depend on UNIT command. WALLS. 2 and 3 information about parameters used for calculation of reinforcement for beams. columns and 2D (two dimensional) members is presented.04 MEMB 1 TO 40 DD2 10. MEMB 23 TO 40 CRA 0.* OUTPUT COMMAND TO PRINT RESULTS OF CALCULATION (ACCORDING TO USER’S JUDGMENT) . . .PERFORM ANALYSIS . * COMMAND OF BEAM REINFORCEMENT CALCULATION DESIGN BEAM 23 TO 40 * COMMAND OF COLUMN REINFORCEMENT CALCULATION DESIGN COLUMN 1 TO 22 * COMMAND OF CALCULATION 2D ELEMENTS (SLABS. . * COMMAND OF LOADING AND THEIR COMBINATIONS CONSIDERED IN DESIGN LOAD LIST 1 5 TO 9 * COMMAND TO START REINFORCEMENT CALCULATION PROCEDURE START CONCRETE DESIGN CODE RUSSIAN . . BCL 20. International Design Codes Manual — 693 . SHELLS) DESIGN ELEMENT 41 TO 252 * COMMAND OF INTERRUPTION REINFORCEMENT CALCULATION END CONCRETE DESIGN In tables 1. its value stays at that specified number until it is specified again.036 MEMB 41 TO 252 . RCL = 2. RCL = 19. RCL = 33. No. if class of reinforcement is A-IV. RCL = 77. if class of reinforcement is Bp-I. RCL = 3.01-84* for beams.Concrete Design Per SNiP 2.03. if class of reinforcement is A-III.15A. Russian Codes . if class of reinforcement is K-7. if class of reinforcement is K-19 l l l l l l l l l l l l 694 — STAAD. if class of reinforcement is A-VII. RCL = 6. if class of reinforcement is A-II.Pro . if class of reinforcement is A-IIIb. RCL = 10. if class of reinforcement is A-VI. RCL = 9. if class of reinforcement is A-V. RCL = 8. Parameter Default name Value 1 2 NLT RCL 1 3 Description Number of long-term loading case Class of longitudinal reinforcement: l RCL = 1. if class of reinforcement is A-I. if class of reinforcement is B-II. if class of reinforcement is Bp-II. RCL = 7. RCL = 4.03. RCL = 5.1-Names of parameters for Concrete design according to Russian Code -СНиП 2.01-84* Table 15A. European Grade: l l l 11 = S240. International Design Codes Manual — 695 . 3 USM 1. Parameter Default name Value 2 RCL 3 Description Class of longitudinal reinforcement: Russian Grade: l l l l l l 1 = A240. 6 = A500SP. 7 BCL 15. 2 = A300. Total product of service conditions coefficients for longitudinal reinforcement (g ) s 4 UB2 0. 12 = S400. Diameter of longitudinal reinforcement bars in beam tension zone Diameter of shear reinforcement bars for beam. 3 = A400.9 Specific service conditions coefficient for concrete (g ) b2 5 DD1 16. 4 = A500.No. Compression class of concrete 6 DD2 16. 13 = S500. 5 = B500. 40 = B40.10 = C8/10 12. Description Compression Class of concrete.03. 8. l l l l l l l l l l l l l l l l l l l l l l l l 10 = B10.85 = C70/85 80. Product of service conditions coefficients for concrete.45 = C35/45 40. 55 = B55.30 = C25/30 30.105 = C90/105 8 UBM 1.15A. 30 = B30.55 = C45/55 50. 16. 35 = B35. 25 = B25.95 = C80/95 90.Concrete Design Per SNiP 2.50 = C50/50 45.15 = C12/15.37 = C30/37 35.01-84* No. except UB2 (g ) b 696 — STAAD. Russian Codes . 60 = B60. 15 = B15 20 = B20.Pro . 50 = B50.60 = C50/60 60.20 = C16/20 25. 45 = B45. Parameter Default name Value 7 BCL 15.75 = C60/75 70. No. Parameter Default name Value 9 TEM 0. Description Parameter of concrete hardening conditions: l TEM=0, for natural hardening conditions; TEM=1, for steam hardening conditions l 10 CL1 0.05 Distance from top/bottom fiber of beam cross section to the center of longitudinal reinforcement bar; Distance from left/right side of beam cross section to the center of longitudinal reinforcement bar Ultimate width of short-term crack Ultimate width of long-term crack Limit state parameter for beam design l 11 CL2 0.05 12 13 14 WST WLT SSE 0.4 0.3 0 SSE=0, if calculation of reinforcement amount must be carried out according to the requirements of load carrying capacity (the first limit state); SSE=1, if calculation of reinforcement amount must be carried out according to the cracking requirements (the second limit state) l International Design Codes Manual — 697 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* No. Parameter Default name Value 15 RSH 1 Description Class of shear reinforcement: l RSH = 1, if class of reinforcement is A-I; RSH = 2, if class of reinforcement is A-II; RSH = 3, if class of reinforcement is A-III; RSH = 33, if class of reinforcement is A-IIIb; RSH = 4, if class of reinforcement is A-IV; RSH = 5, if class of reinforcement is A-V; RSH = 6, if class of reinforcement is A-VI; RSH = 7, if class of reinforcement is A-VII; RSH = 77, if class of reinforcement is K-7; RSH = 8, if class of reinforcement is B-II; RSH = 9, if class of reinforcement is Bp-II; RSH = 10, if class of reinforcement is Bp-I; RSH = 19, if class of reinforcement is K-19 l l l l l l l l l l l l 698 — STAAD.Pro No. Parameter Default name Value 15 RSH 1 Description Class of shear reinforcement: Russian Grade: l l l l l l 1 = A240; 2 = A300; 3 = A400; 4 = A500; 5 = B500; 6 = A500SP; European grade: l l l 11 = S240; 12 = S400; 13 = S500; 16 FWT ZD Design width of beam top flange. Use for beam design only with default value provided as ZD in member properties. Design width of beam bottom flange. Use for beam design only with default value provided as ZB in member properties. Design depth of beam section. Use for beam design only with default value provided as YD in member properties. Face of support location at the start of the beam. Use for beam design only. Face of support location at the end of the beam. Use for beam design only. Number of equally-spaced sections for beam design. Use for beam design only. Upper limit is equal to 20. 17 FWB ZB 18 DEP YD 19 SFA 0. 20 EFA 0. 21 NSE 13 Table 15A.2-Names of parameters for Concrete design according to Russian Code СНиП 2.03.01-84* for columns No. Parameter Default Name Value 1 NLT 1 Description Number of long-term loading case International Design Codes Manual — 699 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* No. Parameter Default Name Value 2 RCL 3 Description Class of longitudinal reinforcement: Russian Grade: l l l l l l 1 = A240; 2 = A300; 3 = A400; 4 = A500; 5 = B500; 6 = A500SP; European Grade: l l l 11 = S240; 12 = S400; 13 = S500; 3 USM 1. Total product of service conditions coefficients for longitudinal reinforcement (g ) s 4 UB2 0.9 Specific service conditions coefficient for concrete (g ) b2 5 DD1 16. Minimum diameter of longitudinal reinforcement bars for column Maximum diameter of longitudinal reinforcement bars for column 6 DD2 16. 700 — STAAD.Pro No. Parameter Default Name Value 7 BCL 15. Description Compression class of concrete: l l l l l l l l l l l l l l l l l l l l l l l l 10 = B10; 15 = B15 20 = B20; 25 = B25; 30 = B30; 35 = B35; 40 = B40; 45 = B45; 50 = B50; 55 = B55; 60 = B60; 8.10 = C8/10 12.15 = C12/15; 16.20 = C16/20 25.30 = C25/30 30.37 = C30/37 35.45 = C35/45 40.50 = C50/50 45.55 = C45/55 50.60 = C50/60 60.75 = C60/75 70.85 = C70/85 80.95 = C80/95 90.105 = C90/105 8 UBM 1. Product of service conditions coefficients for concrete, except UB2 (g ) b International Design Codes Manual — 701 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* No. Parameter Default Name Value 9 TEM 0. Description Parameter of concrete hardening conditions: l TEM=0, for natural hardening conditions; TEM=1, for steam hardening conditions l 10 CL1 0.05 Distance from edge of column cross section to the center of longitudinal reinforcement bar Column's length coefficient to evaluate slenderness effect in local Y axis Column's length coefficient to evaluate slenderness effect in local Z axis Class of shear reinforcement: Russian Grade: l l l l l l 11 ELY 1. 12 ELZ 1. 13 RSH 1. 1 = A240; 2 = A300; 3 = A400; 4 = A500; 5 = B500; 6 = A500SP; European grade: l l l 11 = S240; 12 = S400; 13 = S500; Table 15A.3-Names of parameters for Concrete design according to Russian Code (SNiP 2.03.01-84*) for slabs and/or walls No. Parameter Default Name Value NLT 1 Description 1 Number of long-term loading case 702 — STAAD.Pro No. Parameter Default Name Value RCL 3 Description 2 Class of longitudinal reinforcement: Russian Grade: l l l l l l 1 = A240; 2 = A300; 3 = A400; 4 = A500; 5 = B500; 6 = A500SP; European Grade: l l l 11 = S240; 12 = S400; 13 = S500; 3 USM 1. Total product of service conditions coefficients for longitudinal reinforcement (g ) s 4 UB2 0.9 Specific service conditions coefficient for concrete (g ) b2 5 SDX 16. Diameter of reinforcing bars located in the first local (X) direction of slab/wall Diameter of reinforcing bars located in the second local (Y) direction of slab/wall 6 SDY 16. International Design Codes Manual — 703 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* No. Parameter Default Name Value BCL 15. Description 7 Compression class of concrete: l l l l l l l l l l l l l l l l l l l l l l l l 10 = B10; 15 = B15 20 = B20; 25 = B25; 30 = B30; 35 = B35; 40 = B40; 45 = B45; 50 = B50; 55 = B55; 60 = B60; 8.10 = C8/10 12.15 = C12/15; 16.20 = C16/20 25.30 = C25/30 30.37 = C30/37 35.45 = C35/45 40.50 = C50/50 45.55 = C45/55 50.60 = C50/60 60.75 = C60/75 70.85 = C70/85 80.95 = C80/95 90.105 = C90/105 8 UBM 1. Product of service conditions coefficients for concrete, except UB2 (g ) b 704 — STAAD.Pro No. Parameter Default Name Value TEM 0. Description 9 Parameter of concrete hardening conditions: l TEM=0, for natural hardening conditions; TEM=1, for steam hardening conditions l 10 CL 0.05 Distance from top/bottom face of slab/wall element to the center of longitudinal reinforcing bars located in first local (X) direction. (Main thickness of top/bottom concrete cover for slab/wall element) Distance from top/bottom face of slab/wall element to the center of transverse reinforcing bars located in second local (Y) direction (Secondary thickness of top/bottom concrete cover for slab/wall) Ultimate width of short-term crack Ultimate width of long-term crack 11 CRA 0.05 12 13 WST WLT 0.4 0.3 International Design Codes Manual — 705 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* No. Parameter Default Name Value STA 0 Description 14 Parameter of limit state for slab/wall design: l STA=0, if calculation of nonsymmetrical reinforcement must be carried out according to the requirements of load carrying capacity (the first limit state); STA=1, if calculation of symmetrical reinforcement must be carried out according to the requirements of load carrying capacity (the first limit state); STA=2, if calculation of nonsymmetrical reinforcement must be carried according to the cracking requirements (the second limit state); STA=3, if calculation of symmetrical reinforcement must be carried according to the cracking requirements (the second limit state) l l l 15 SELX 0. Design length of wall member to evaluate slenderness effect in local X axis Design length of wall member to evaluate slenderness effect in local Y axis Design parameter of slab/wall reinforcement: l 16 SELY 0. 17 MMA 0 MMA=0, if reinforcement calculation must be applied by stresses in local axis; MMA=1, if reinforcement calculation must be applied by principal stresses l 706 — STAAD.Pro No. Parameter Default Name Value MMB 1 Description 18 Design parameter of slab/wall reinforcement: l MMB=0, if the effect of additional eccentricity is not taken into account; MMB=1, if the effect of additional eccentricity is taken into account l 19 RSH 1. Class of shear reinforcement: Russian Grade: l l l l l l 1 = A240; 2 = A300; 3 = A400; 4 = A500; 5 = B500; 6 = A500SP; European grade: l l l 11 = S240; 12 = S400; 13 = S500; 15A.3 Beams Reinforcement for beams of rectangular and T cross-section can be calculated. In calculation of longitudinal reinforcement bending moment about local axis and torsional moments are considered, but influence of longitudinal forces and bending moments in relation to local axis is ignored. In calculation of transverse reinforcement shear forces parallel to local axis and torsional moments are taken into account. Reinforcement for beams can be calculated either from conditions of strength or from conditions of open crack width limitation (see parameter SSE). Parameters SFA and ЕFA are considered only in calculation of transverse reinforcement. In general case calculation of reinforcement for beams is carried out two times – according to strength conditions and according to conditions of open crack width limitation. In reinforcement calculations from conditions of strength design values of load have to be taken and in calculations from conditions of crack width limitation – characteristic (normative) load International Design Codes Manual — 707 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* values are used. Both calculations can be carried out in one session with the use multiple analysis possibility of the program STAAD.Pro. In most cases calculation of reinforcement is carried out with account only of a part of loadings. In such cases command LOAD LIST is used, in which numbers of loads considered in calculation are indicated. Number of permanent and long-term loads equal to parameter NLT must be included into the list of considered loads. It has to be noted, that values of parameters DD1 and DD2 have influence not only on the width of opened crack but also in some cases, on design and normative reinforcement resistances. Parameter BCL can be equal to any value of concrete compression strength class given in SNiP 2.03.01-84* and to any intermediate value as well. It should be remembered, that accuracy of results of calculation of transverse reinforcement increases with the value of parameter NSE. Parameters SFA and ЕFA are considered only in calculations of transverse reinforcement. Beam 1 is shown in Figure 2 with rigid intervals the lengths of which are: at the start of the beam 0.3m and at the end – 0.2m. In modeling of the beam the following command can be used. MEMBER OFFSET 1 START 0.3 0 0 1 END -0.2 0 0 Figure 12A.2 - Diagram of a beam with rigid intervals When command MEMBER OFFSET is used forces corresponding to the beam the length of which is equal to the distance between points a and b are calculated and then used in calculation of reinforcement. In such case it is necessary to take into account default values of parameters SFA and ЕFA equal to zero. When command MEMBER OFFSET is not used forces corresponding to the beam the length of which is equal to the distance between points 10 and 11 are calculated and then used in calculation of reinforcement. In this case it is necessary to consider values of parameters SFA=0.3 and ЕFA=0,2 in reinforcement calculation. 708 — STAAD.Pro In both cases calculated quantity of transverse reinforcement will be the same. Calculated quantity of longitudinal reinforcement in the second case will be greater. For beam the following output is generated: l beam number; method of calculation (according to conditions of strength or limitations of opened crack width); l l length and cross-sectional dimensions; distance from resultant of forces acting in bottom/top reinforcement to bottom/top edge of the section; l distance from the side edge of cross-section of the beam web to the centroid of longitudinal bars located at this edge; l l concrete class; class of longitudinal and transverse reinforcement; assumed in calculations bar diameters of longitudinal and transverse reinforcement; calculation results of longitudinal and transverse reinforcement (in two tables). l l l In nine columns of the first table the following results are presented: Table 15A.4-Beam design output 1 Result Section AsAs+ Moments (-/+) Load. N. (-/+) Acrc1 Acrc2 Description distance of the section from the “start” of the beam, мм cross-sectional area of longitudinal reinforcement in the bottom zone of crosssection of the beam, if angle BETA=0°, or in the top zone, if BETA=180° , sq.cm cross-sectional area of longitudinal reinforcement in the top zone of cross-section of the beam , if angle BETA=0°, or in the top zone, if BETA=180° , sq.cm values of bending moments, determining cross-sectional areas of longitudinal reinforcement As- and As+ , kNm numbers of loading versions, determining cross-sectional areas of longitudinal reinforcement short-term opened crack width*, mm long-term opened crack width*, mm * Opened crack width is presented only in the case when calculation is performed according to conditions limiting opened crack width. In ten columns of second table the following results are presented: International Design Codes Manual — 709 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* Table 15A.5-Beam design output 2 Result Section Qsw Asw Q T Load N. Description distance of the section from the “start” of the beam, mm intensity of transverse reinforcement, kN/m cross-sectional area of transverse bars, sq.cm, if their step is 10, 15, 20, 25 or 30 cm value of shear force parallel to the local axis, kN value of torsional moment, kNm number of loading version, determining intensity of transverse reinforcement An example of output of calculation results is presented below. BEAM NO. 23 DESIGN RESULTS (by limitation of crack width) Length - 6000 mm. Section: BF1= 550 mm, B= 200 mm, HF1=220 mm, H=450 mm. Distance from top/bottom surface of beam to center of longitudinal reinforcement - 40 mm. Distance from side surface of beam to center of longitudinal reinforcement - 30 mm. Concrete class - В25.0 (Rb=13.05 MPa; Rbt=0.94 MPa; Gb2=0.9). Class of longitudinal reinforcement - А-III (Rs=365.0 MPa; Rsc=365.0 MPa). Diameter of longitudinal reinforcement bars D=16 mm. Class of shear reinforcement - А-I (Rsw=175.0 MPa). Diameter of shear reinforcement bars Dw=10 mm. L O N G I T U D I N A L R E I N F O R C E M E N T Section As-As+ Moments(-/+) Load.N.(-/+) Acrc1 Acrc2 mm sq.cm kNm mm mm -------------------------------------------------------------------- 0. 500. 1000. 1500. 2000. 2500. 10.92 4.74 1.13 1.13 1.13 1.13 0.41 0.41 1.13 6.41 9.24 11.53 -152. -5. -8. -11. -14. / 2. / 17. / 75. / 115. / 139. 6 / 4 0.237 5 / 0 0.294 4 / 6 0.000 4 / 6 0.295 4 / 6 0.298 4 / 6 0.271 0.121 0.157 0.000 0.147 0.149 0.134 -60. / 0. 710 — STAAD.Pro 3000. 3500. 4000. 4500. 5000. 5500. 6000. 1.19 1.41 1.63 1.95 3.23 0.74 16.89 12.16 10.86 8.28 4.54 0.58 0.41 0.41 -18. -21. / 144. / 132. 4 / 6 0.263 4 / 6 0.277 4 / 6 0.296 4 / 6 0.299 5 / 3 0.293 5 / 0 0.271 5 / 0 0.155 0.127 0.130 0.129 0.093 0.157 0.142 0.078 -24. / 103. -27. / 56. -39. / 9. -124. -226. / 0. / 0. S H E A R R E I N F O R C E M E N T Section Qsw Asw, cm^2, if Sw= Q T Load mm kN/m 10cm 15cm 20cm 25cm 30cm kN kNm N. 0. 500. 1000. 1500. 2000. 2500. 3000. 3500. 4000. 4500. 5000. 5500. 6000. 95.0 242.5 302.5 302.5 251.3 251.3 174.5 63.9 1.44 2.15 1.44 2.15 1.00 1.50 0.36 0.55 2.87 2.87 1.99 0.73 3.59 3.59 2.49 0.91 4.31 -203.9 4.31 -168.9 2.99 -133.9 1.09 -98.9 0.0 6 0.0 6 0.0 6 0.0 6 -63.9 -28.9 12.7 47.7 82.7 117.7 152.7 187.7 216.1 0.0 5 0.0 5 0.0 5 0.0 5 0.0 6 0.0 6 0.0 5 0.0 5 0.0 5 Minimum detailing requirements ! Minimum detailing requirements ! Minimum detailing requirements ! Minimum detailing requirements ! Minimum detailing requirements ! 0.55 0.82 1.39 2.08 1.73 2.59 1.73 2.59 1.09 2.77 3.46 3.46 1.37 3.46 4.32 4.32 1.64 4.16 5.19 5.19 Here Minimum detailing requirements! means that reinforcement is not required according to calculation. 15A.4 Columns Reinforcement for columns of rectangular or circular cross-section can be calculated. Flexibility of columns can be evaluated in two ways. In the case of usual analysis (command PERFORM ANALYSIS) flexibility is assessed by parameters ELY and ELZ, values of which should conform with recommendation of the Code SNiP 2.03.01-84*. If P-DELTA (analysis according to deformed diagram) or NONLINEAR (nonlinear geometry) analysis is performed, values of parameters ELY and ELZ should be close to zero, for example ELY = ELZ=0.01. Longitudinal reinforcement for columns is calculated only from condition of strength. Longitudinal forces and bending moments in relation to local axes account in longitudinal reinforcement calculations. For rectangular columns the following output is generated: International Design Codes Manual — 711 and are taken into 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* l column number; column length and cross-sectional dimensions; l distance of centroid of each longitudinal bar from the nearest edge of the crosssection; l l concrete class; longitudinal reinforcement class; range of longitudinal reinforcement bar diameters assumed in calculation; diameter of longitudinal reinforcement bars obtained in calculation; total quantity of longitudinal bars; quantity of longitudinal bars at each cross-section edge, directed parallel to the local ; l l l l l axis l quantity of longitudinal bars at each cross-section edge, directed parallel to the local . axis In nine columns of the table under the heading LONGITUDINAL REINFORCEMENT the following output is presented: Table 15A.6-Column design output 1 Result Section Astot Asy distance of the section from the “start” of the column, mm total cross-sectional area of longitudinal reinforcement, sq.cm cross-sectional area of longitudinal reinforcement bars at each edge of section, directed parallel to the local axis Asz , sq.cm cross-sectional area of longitudinal reinforcement bars at each edge of section, directed parallel to the local axis , sq.cm Percent Nx, Mz, My reinforcement percentage in the section respective values of longitudinal force and bending moments in relation to the local axes and , determining cross-sectional area of longitudinal reinforcement Load.N. number of loading version, determining cross-sectional area of longitudinal reinforcement An example of output of calculation results is presented below. COLUMN NO. 97 DESIGN RESULTS (rectangular section) Length - 4000 mm. Section: B= 350 mm, H=350 mm. Distance from edge of column cross section to center of each longitudinal 712 — STAAD.Pro reinforcement bar - 40 mm. Concrete class - В25.0 (Rb=13.05 МPa; Gb2=0.9). Class of longitudinal reinforcement - А-III (Rs=365.0 МPa; Rsc=365.0 МPa). Diameter range of longitudinal reinforcement bars: Dmin=16 mm . . . Dmax=32 mm Diameter of longitudinal reinforcement bars from calculation d=20 mm. Total number of reinforcement bars Ntot=6. Number of longitudinal bars at each section edge parallel to the local Y axis Nyy =2. Number of longitudinal bars at each section edge parallel to the local Z axis Nzz =3. L O N G I T U D I N A L R E I N F O R C E M E N T Section m 0. 4000. Astot sq.cm 16.42 15.35 Asy sq.cm 3.01 3.01 Asz sq.cm 6.20 5.67 Percent % 1.34 1.25 Nx kN 285.5 397.3 Mz kNm 81.9 95.3 My kNm 0.0 0.0 Load N 6 5 Diameter of longitudinal reinforcement bars, total quantity of longitudinal bars as well as quantity of longitudinal bars at each edge of the section obtained from calculation should be considered as recommendation. In this case arrangement of reinforcement in the section depends on the orientation of the local axes and is as follows: Calculated values of reinforcement cross-sectional areas are presented in the table and they may differ from recommended on the lower side. When it is not possible according to detailing provisions to arrange in the column longitudinal reinforcement determined from calculation additional message is derived. For columns of circular section the following output is generated: l column number; column length and diameter of cross-section; l International Design Codes Manual — 713 15A. Russian Codes - Concrete Design Per SNiP 2.03.01-84* l distance of centroid of each longitudinal bar to the edge of cross-section; longitudinal reinforcement class; assumed in calculation range of diameters of longitudinal reinforcement bars; diameter of longitudinal reinforcement bars obtained from calculation; quantity of longitudinal bars. l l l l In seven columns of the table under the heading LONGITUDINAL REINFORCEMENT the following results are presented: Section distance of the section from the “start” of the column, mm Astot Per cent Nx, respective values of longitudinal force and bending moments in relation to local and reinforcement reinforcement , determining cross-sectional area of longitudinal Mz, My axis Load. N. total cross-sectional area of longitudinal reinforcement, sq.cm percentage of longitudinal reinforcement number of loading version, determining cross-sectional area of longitudinal An example of output of calculation results for a column of circular section is presented below. COLUMN NO. 80 DESIGN RESULTS (circular section) Length - 4000 mm. Diameter: Dс= 350 mm. Distance from edge of column cross section to center of each longitudinal reinforcement bar - 50 mm. Concrete class - В20.0 (Rb=10.35 МPa; Gb2=0.9). Class of longitudinal reinforcement - А-III (Rs=365.0 МPa; Rsc=365.0 МPa). Diameter range of longitudinal reinforcement bars: Dmin=16 mm . . . Dmax=32 mm Diameter of longitudinal reinforcement bars from calculation D=20 mm. Total number of reinforcement bars Ntot =7. L O N G I T U D I N A L R E I N F O R C E M E N T 714 — STAAD.Pro When according to detailing provisions it is not possible to arrange in the column longitudinal reinforcement obtained from calculation additional message is derived.1 195.Pro. total quantity of longitudinal bars as well as quantity of longitudinal bars at each edge of the section should be considered as recommendation.86 Percent % 1. Astot sq.8 80. walls. Symmetric or nonsymmetrical reinforcement of 2D members is calculated according to conditions of strength or according to conditions of limiting opened crack width (see for example STA). design values of loads have to be used. In reinforcement calculation for 2D members it is necessary to pay attention to arrangement of local axes of member and direction of reinforcement (see for example CL and CRA).1 Mz kNm 59.96 21. shells) In general case calculation of reinforcement for 2D members is carried out two times – according to conditions of strength and conditions of limiting opened width of cracks.Section m 0.2 My kNm 0.5 Two DimensionalElement (slabs.87 2. 4000. Arrangement of reinforcement in section in this case is shown below: Calculated cross-sectional areas of reinforcement presented in the table may differ from recommended on the lower side. Both calculations can be made in one session taking advantage of multiple analysis possibility of the program STAAD.27 Nx kN 195.0 0. 15A. and for conditions of limiting crack width – characteristic (normative) loads are employed.cm 17. International Design Codes Manual — 715 . If reinforcement is calculated according to conditions of strength.0 Load N 5 5 Diameter of longitudinal reinforcement bars. cm/m distributed bending moment in respect to the local axis . TOP . 0.00 Load N.cm/m 60 TOP BOT 61 TOP BOT 62 TOP BOT Here: Table 15A.00 3.4.00 3. determining intensity of reinforcing in the second direction 716 — STAAD.10.87 0.5 .9.00 0. Russian Codes .6 Ny kN/m 0.9.(Y) -see Fig.00 0.46 0.4 .6 .cm/m 0.5.10 Mx kNm/m . distributed longitudinal force directed parallel to the local axis kN/m number of loading version.4.65 0.00 0.77 My kNm/m .(X) Asy My Ny Load N.01-84* An example of output of calculation results is presented bellow.2 Nx kN/m 0.11. determining intensity of reinforcing in the first direction intensity of reinforcing in the second direction (parallel to the local axis sq.2) ). (Y) 1 3 1 3 1 3 intensity of reinforcing in the first direction (parallel to the local axis sq.9 .9.5.00 0.03.00 0.00 Load.7 .00 4.00 0.15A.00 0.“top” zone of member.9 . BOT . (X) 1 3 1 3 1 3 Asy sq.“bottom” zone of member (“top” zone of member is determined by positive direction of local axis Asx Mx Nx Load N.Concrete Design Per SNiP 2.cm/m distributed bending moment in respect to the local axis kNm/m ).N.53 0.00 0.4. kNm/m number of loading version.00 3.00 0.00 0.7-Slab design output Result Element Description number of finite element.00 3.8.Pro . kNm/m distributed longitudinal force directed parallel to the axis .8 .7 .9 .4.00 3.3 . SLAB/WALL DESIGN RESULTS (by stresses in local axes for limitation of crack width) Element Asx sq. Figure 2 .Local coordinate system of 2D member and notation of forces International Design Codes Manual — 717 . Pro .718 — STAAD. In this version of the program only members from rolled. which is defined in SNiP 2. deviations.15B.81* are presented in the following tables.. Eurozone Design Codes SELECT Code Pack.Steel Design Per SNiP 2. Analysis of structures for the second limit state is performed using service (normative) loads and actions. failure..Pro is capable of performing steel design based on the Russian code СНиП II-23-81* Часть II Нормы проектирования Стальные конструкции (SNiP 2..85 “Loads and Actions”. Design of other members of compound section will be presented in other versions of the program. Relation between design and normative loads is referred to as coefficient of load reliability. l The second group is concerned with states of structures making worse normal their service or reducing durability due to not allowable deflections. yielding of materials or opening of cracks. Economy of selected section is indicated by ratio (RATIO) σ/Ry yc presented in calculation results. Russian Codes .07.07.9 – 0.01. etc. vibrations. which can cause failure of structures.01. qualitative changes in configuration of structure.23-81* Part II Design Standards for Steel Construction).23-81* requires the STAAD E.01.1 General Design Code SNiP Steel Structures as majority of modern codes is based on the method of limit states.07. settlements.2 Built-in Russian Steel Section Library Typical sections of members being checked and selected according to SNiP 2. The first group is concerned with losses of general shape and stability. l Analysis of structures for the first limit state is performed using the maximum (design) loads and actions. Design of members per SNiP 2. 15B. tube and roll-formed assortment sections and also from compound such as double angles of T-type sections.85 shall be taken in to account determining loads or their combinations. International Design Codes Manual — 719 . The following groups of limit states are defined in the Code. A section is economical when said ratio equals to 0.23-81* (Edition 1999) STAAD. 15B. Coefficient of reliability for destination GAMA n according to SNiP 2.95. displacements. Appearance of non-allowable residual deformations. double channels are presented. Steel Design Per SNiP 2.23-81* (Edition 1999) Table 15B.15B.003 WT 0.12 DT 0.16 720 — STAAD.102 ID 0.1-Typical Sections for Russian Steel Design Section I-beam (GOST 8239-89) Regular I-beam (GOST 26020-83) Broad-flanged I-beam (GOST 26020-83) Column I-beam (GOST 26020-83) Channel (GOST 8240-89) Section Type Designation form ST I12 ST B1-10 ST SH1-23 ST K1-20 ST C14 Equal legs angle (GOST 8509-89) ST L100x100x7 RA L100x100x7 Unequal legs angle (GOST 8510-89) ST L125x80x10 RA L125x80x10 Pipes (welded and for gas piping) ST PIP102x5.5 or ST PIPE OD 0.055 Roll-formed square and rectangular tubes ST TUB160x120x3 or ST TUBE TH 0.Pro . Russian Codes . 01 (SP – clear distance between angle walls) Double unequal legs angles with long legs back to back LD L125x80x10 SP 0.Table 15B. or at the bottom part if beta angle = 180°. International Design Codes Manual — 721 .01 (SP – clear distance between angle walls) Double unequal legs angles with short legs back to back SD L125x80x10 SP 0. For entry of cross-sectional dimensions command MEMBER PROPERTIES RUSSIAN is used.01 (SP – clear distance between angle walls) Tee with flange at the top T I12 T B1-10 T SH1-23 T K1-20 Double channels Note: Flange of Tee beam is at the top part of cross-section if beta angle = 0°.2-Compound Sections for Russian Steel Design Section Section Type Designation form D C14 SP 0.01 (SP – clear distance between channel walls) Double equal legs angles LD L100x100x7 SP 0. 23-81* (Edition 1999) 15B. 722 — STAAD. In this program version only assortment sections can be utilized. AS A RULE.01 * MEMBER OF TEE SECTION 106 TO 126 TABLE T SH1-23 * FLANGE OF T-BEAMS AT THE BOTTOM OF CROSS-SECTION BETA 180.055 * SQUARE TUBE FROM ASSORTMENT 61 TO 68 TABLE ST TUB120X120X3 * RECTANGULAR TUBE OF CROSS-SECTIONAL DIMENSION DEFINED BY CLIENT 69 TO 95 TABLE ST TUBE TH 0.16 * DOUBLE CHANNEL (DISTANCE BETWEEN WALLS 10 ММ) 96 TO 103 TABLE D C14 SP 0.12 DT 0.102 ID 0. Russian Codes .003 WT 0. MEMB 116 TO 126 * ORIENTATION OF THE LOCAL ANGLE AXES IN RELATION TO THE GLOBAL AXES OF THE STRUCTURE BETA RANGLE MEMB 12 TO 30 COMMANDS OF OUTPUT DATA FOR CHECK AND SELECTION OF SECTIONS ARE LOCATED AFTER COMMANDS OF ANALYSIS AND.5 * ROUND PIPE OF CROSS-SECTIONAL DIMENSIONS DEFINED BY CLIENT 47 TO 60 TABLE ST PIPE OD 0. AFTER OUTPUT COMMAND TO PRINT RESULTS OF CALCULATION. 15B.Steel Design Per SNiP 2.2.Pro .15B.01 * DOUBLE UNEQUAL LEGS ANGLES WITH SHORT LEGS BACK-TO-BACK (DISTANCE BETWEEN WALLS 10 ММ) 104 TO 105 TABLE SD L125X80X10 SP 0.3 Member Capacities Algorithms for selection and review of sections for steel members according to assortments and databases of the main rolled steel producers from given countries and according to international standards as well are included in STAAD.Pro program.1 Example UNITS METER MEMBER PROPERTY RUSSIAN * I-BEAM 1 TO 6 TABLE ST B1-10 * CHANNEL 7 TO 11 TABLE ST C14 * UNEQUAL LEGS ANGLE 12 TO 30 TABLE RA L125X80X10 * ROUND ASSORTMENT PIPE 31 TO 46 TABLE ST PIP102X5. Net section International Design Codes Manual — 723 .07. c Slenderness of tension member (CMM) shall not exceed slenderness limit indicated in table 20 of SNiP 2. ALL Obligatory parameter LY 4..3. MEM 1 TO 4 MAIN 1.01.81*. ALL SGR 3. ALL SBLT 0 ALL * PARAMETER OF OUTPUT AMOUNT OF INFORMATION ON CALCULATION RESULTS TRACK 2. table 6 of SNiP 2. MEMB 1 TO 4 LZ 4.3. * COMMAND TO START SECTION CHECK PROCEDURE CHECK CODE ALL * COMMAND TO START SECTION SELECTION PROCEDURE SELECT ALL .2 Axial tension members Stress in a section of axial tension member shall not exceed design strength R of selected steel y multiplied by coefficient of service conditions γ (KY and KZ).15B.01..81* (default value λu = 200.1 Example * COMMAND OF ANALYSIS PERFORM ANALYSIS * COMMAND OF LOADINGS AND THEIR COMBINATIONS CONSIDERED IN DESIGN LOAD LIST 1 5 TO 9 * COMMAND TO START DESIGN ACCORDING TO RUSSIAN CODE PARAMETER CODE RUSSIAN * LIST OF PARAMETERS USED IN CHECKING AND SELECTING BEAM 1. but another value can be defined). * COMMAND OF OUTPUT TO PRINT CONTENT OF ASSORTMENT TABLES PRINT ENTIRE TABLE * COMMAND OF OUTPUT TO PRINT SUMMARY OF STEEL ACCORDING TO SECTIONS STEEL TAKE OFF * COMMAND OF OUTPUT TO PRINT SUMMARY OF STEEL ACCORDING TO MEMBERS AND SECTIONS STEEL MEMBER TAKE OFF 15B. ALL .07. 07. Deflections and displacements”.0.01.81* principal stresses are checked.01..14 of SNiP 2.e.23-81* (Edition 1999) factor (ratio Anet/Agross (NSF)) is used for tension member to allow for reduction of design cross-section area.15B.15 of SNiP 2.3 of SNiP 2. buckling coefficient and design resistance of steel. Limit values of deflection are determined in accordance with SNiP 2.07.81* and are set by specification of members.07. as well as fixation of ends (l0 = μl).07.81*.81*.Steel Design Per SNiP 2.. Normal stresses are calculated in the outermost section fibres. section area. stability and deflection..85 “Loads and Actions.3. Calculation of flexural members consists of verification of strength. i.81*).01. 15B. Limit slenderness value depends on stress acting in the member. Addition chapter 10.81*. Additional data about load (concentrated or distributed). 15B. Russian Codes . Simply supported (non-continuous) beams can be calculated in elastic as well as in elasticplastic state according to requirements of clause 5. which is specified..Pro .01.81*.07.07. location of applied load are required.81*.. Verification of deflection is performed only in the case of review (CHECK) problem.01. The calculation is performed in accordance with the clause 5. If normal stresses do not exceed design steel strength and tangential stresses do not exceed design value of steel shear strength Rsγs then according to clause 5.01. numbers of bracing restrains of compression flanges. Slenderness of compression members (CMN) shall not exceed limit values given in table 19 of SNiP 2..01.18 of SNiP 2. buckling coefficient φ is determined by formula 8-10. Since slenderness can be different in various planes the greatest slenderness is assumed in calculations. Value of coefficient α being used in table 19 is taken within limits from 0. with allowance for slenderness (λ = l0 /imin ).01.07. in input data.07. are determined according to requirements of chapter 6 or addition 6 to SNiP 2.0. Coefficient φb value is determined according to appendix 7 of SNiP 2.3 Axial compression members All axial compression members are calculated as long bars. Calculation can be selected by specification of structure in input data. General stability of member subjected to bending in one plane are calculated in accordance with clause 5.07. Tangential stresses are verified in the neutral axis zone of the same section. Effective bar lengths (within and out of plane) taking in to account role and location of the bar in the structure. Stiffness of flexural members is verified comparing input value of deflection limit (through parameter DFF) with maximum displacement of a section of flexural member allowing for load reliability coefficient.. and subjected to bending in two planes – in accordance with “Guide to design of steel structures” (to SNiP 2..3.5 to 1.01. For closed sections it is assumed that coefficient φb = 1.4 Flexural members Members subjected to the action of bending moments and shear forces are called flexural members. 724 — STAAD.. Normal and tangential stresses are verified by strength calculation of members. when mef< 20 strength by formula 49 is not verified (clause 5. In determination of steel parameters SBLT and MAIN shall be approved (see Table 12B.24).81* there is common database of equal legs angles and unequal legs angles. which differ from.25 of SNiP 2.01.32 or 5.34.81* resistance of eccentric compression/tension member taking into consideration condition Ry < 530 MPa.4 Design Parameters Information on parameters. Values of parameters do not depend on command UNIT. therefore solution of section selection problem may give equal legs angle as well as unequal legs angle irrespective of set at the beginning.27. Bending moment appears due to eccentric application of longitudinal force or due to transverse force.01.3. 15B.. Parameters CMN and CMM give opportunity to set slenderness limit for compression and tension members respectively for their stability calculation. 5.5Rs and N/(An Ry ) > 0. When reduced relative eccentricity mef> 20 eccentric compression members are calculated as flexural members (N = 0). In the case of application of steel not defined by SNiP and/or GOST it is necessary to set their design strength by parameters UNL and PY. Only these values of parameters. Following the requirements of clause 5. and in other cases-by formula 50.81*. τ < 0. or refuse consideration of slenderness by setting default parameters.5 Eccentric compression/tension members Eccentric compression or tension members are subjected to simultaneous action of axial force and bending moment.01.07. International Design Codes Manual — 725 .4).30. defined in the program need to be included in the input data file. Calculations of stability verification are performed according to requirements of clauses 5. Stress in eccentric compression/tension members is obtained as a sum of stresses due to axial force and bending.1 is calculated by formula 49. Check for deflection performed by setting parameter DFF (maximum allowable relative deflection value) different from set in the program. Selection of section (command SELECT) can be performed only according to the first group of limit states with subsequent recalculation and verification of selected section with allowance for deflection. Calculation for the first group of limit states involves selection of members according to strength and stability. Review of sections (command CHECK) can be performed according to the first and the second group of limit states.. In this case selection of sections will be performed with consideration only of strength check. The same is and with rectangular and square tubes.. data used for check and selection of sections in design of steel structures according to Russian Code is presented in the following table. Calculation for strength of eccentric tension members is made according to formula 50 of SNiP 2.07.15B.07. In this version of calculation according to requirements of SNiP 2. 5. 15B.3-Parameters for Steel design according to Russian Code (SNiP II – 23 – 81*. BEAM = 2. edition 1990) Parameter Name Default Value Description Member design parameter: l BEAM = 0.Steel Design Per SNiP 2. Russian Codes . Design members for forces at their ends or at the sections defined by SECTION command. its value stays at that specified number until it is specified again. for loading on bottom flange l 726 — STAAD. Same as BEAM=1. BEAM = 3.23-81* (Edition 1999) Note: Once a parameter is specified. Calculate forces at 13 points and perform design checks at all locations including the ends l BEAM 1 l l Place of loading on beam: CB 1 l CB = 1. This is the way STAAD works for all codes. but additional checks are carried out at beam ends and at critical inter mediate section. for loading on top flange.Pro . CB = 2. BEAM = 1. Table 15B. Calculate the major axis moment Mz at 13 points along the beam and design beam at the location of maximum Mz. if ultimate slenderness value is "300". if ultimate slenderness value is "350". СMM = 3. if ultimate slenderness value is "200". СMM = 4. if slenderness is suppressed. if ultimate slenderness value is "250".Parameter Name Default Value Description Slenderness limit value for tension members: l СMM = 0. if ultimate slenderness value is "150". СMM = 2. if ultimate slenderness value is "400 l l l СMM 0 l l l Set slenderness limit value not equal to "0" for design with evaluation of buckling effect International Design Codes Manual — 727 . СMM = 2. СMM = 6. СMM = 5. if slenderness limit value is "200". if slenderness limit value is "21060a".23-81* (Edition 1999) Parameter Name Default Value Description Slenderness limit value for compression members: l СMN = 0. if slenderness is suppressed.Steel Design Per SNiP 2. if slenderness limit value is "220". if slenderness limit value is "150". СMN = 3. СMN = 5. if slenderness limit value is "21060a". [m] DMIN 0. СMN = 9. СMN = 8. Default value 0 is valid if design is applied without deflection limitation.15B. Russian Codes . СMN = 4. if slenderness limit value is "18060a". if slenderness limit value is "21060a". l l l l CMN 0 l l l l l Set slenderness limit value not equal to "0" for design with evaluation of buckling effect Allowable limit of relative local deflection (Member length/Deflection Ratio): DFF 0. СMN = 7. СMN = 6. if slenderness limit value is "120". СMN = 1. [m] Minimum allowable section depth Maximum allowable section depth 728 — STAAD. if slenderness limit value is "220-40a". СMN = 2. Set for deflection check only DMAX 1.Pro . LEG = 4.0 KY 1. for loading uniformly distributed on bracket l LEG 4 l l l LY [m] Effective length in respect to local axis Y (in Member plane XZ) length Default is selected member's length Effective length in respect to local axis Z (in Member plane XY) length Default is selected member's length LZ [m] International Design Codes Manual — 729 . LEG = 5. LEG = 2. for loading concentrated at the end of bracket. LEG = 3.0 LEG = 1.0 Description Specific service condition coefficient for buckling design Specific service condition coefficient for strength design Coefficient of effective length in respect to local axis Y (in plane XZ) Coefficient of effective length in respect to local axis Z (in plane XY) Type and position of loading on beam: l GAMC2 1. for loading uniformly distributed on beam. for loading concentrated in the middle span. for loading concentrated in the quarter of the span.0 KZ 1.Parameter Name GAMC1 Default Value 1. MAIN = 5. if Standard of steel grade is GOST27772-88. MAIN = 2. MAIN = 3.Steel Design Per SNiP 2. if Standard of steel grade is GOST8731-87. if beam not fixed. if Standard of steel grade is GOST10705-80. if Standard of steel grade is TY14-3-567-76 l MAIN 1 l l l NSF 1.15B. one restraint in the middle of the span.0 Net section factor for tension members or web section area weakening factor for bending members Design steel strength (yield strength): PY 0 [MPa] If parameters MAIN according to Standard of steel grade (GOST) and by SGR according to Steel grade (STAL) are not defined Ratio between design and characteristic loads values Number of lateral bracing restraints along the span: l RATIO 1. etc. number of uniformly spaced lateral supports along the span SBLT 0 l l 730 — STAAD. if Standard of steel grade is GOST10706-76. SBLT = 2. Russian Codes .Pro .23-81* (Edition 1999) Parameter Name Default Value Description Standard of steel grade (GOST): l MAIN = 1. SBLT = 1. MAIN = 4. 3.0 SBLT = 0. for elastic calculation TB = 1. for advanced output information TRACK 0 l l Design steel strength (ultimate strength): UNL 0 [MPa] If parameters MAIN according to Standard of steel grade (GOST) and by SGR according to Steel grade (STAL) are not defined International Design Codes Manual — 731 . TRACK = 1. TRACK = 2.4 below. for elastic-plastic calculation TB 0 l Set for members under bending or non-axial compression/tension only. for extended output information. for suppressed output information. Indication of elastic or elastic-plastic calculation: l TB = 0. Output parameter: l TRACK = 0.Parameter Name Default Value Description SGR 1 Steel grade (STAL). Refer to Table 12B. F GT. F GT. F F F F F F Tube 2 15 BSt3ps 2 16 BSt3sp 17 18 20 4 16G2АF 5 *GT – members from sheet and roll-formed tubes F – rolled section steel 732 — STAAD.15B. F GT.07.01.Pro .-81* (table 51 and 51a) SGR Value 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Steel C235 C245 C255 C275 C285 C345 C345K C375 C390 C390K C440 C590 C590К BSt3kp 1 1 1 1 1 1 1 1 1 1 1 1 1 2 Parameter MAIN GOST GOST 27772-88 “ “ “ “ “ “ “ “ “ “ “ “ GOST 1070580* GOST 1070580* Tube 3 GOST 1070676* GOST 1070580* Tube 3 GOST 1070676* GOST 8731-87 TY 14-3-567-76 Tube Tube For members* GT. Russian Codes . F GT.4-Steel types for design of steel structures according to SNiP 2.Steel Design Per SNiP 2.23-81* (Edition 1999) Table 15B. F GT. F GT. F GT. Output of selection and check results are given in suppressed. bending moments in relation to local member axes Z and Y. extended and advanced forms. according to which strength safety of the member is minimum. extended .3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 5. number of check clause. In tables of results common data for all TRACKs are indicated: number of member. 15B. abbreviated name of normative document (code.15B. In tables of results common data for all TRACKs are indicated: (TRACK=2). distance to section.results according to all check conditions (TRACK=1) and advanced – complete information on results of member design (TRACK=2). safety of strength (ratio between design and normative values).48. FAILURE – are not met). Form of output results depends on value of parameter TRACK.5 of the Technical Reference Manual for general information on Code Checking.23-81*. Results are presented in tables. value of longitudinal force acting in the member with subscript indicating its direction (“C” – compression.48. Refer to Section 5. ======================================================================== MEMBER CROSS RESULT/ CRITICAL COND/ RATIO/ LOADING/ International Design Codes Manual — 733 . type and number of cross-section.5.2 of the Technical Reference Manual for details the specification of the Code Checking command. Refer to Section 2. number of the most unfavorable loading.1 Example of TRACK 0 output In suppressed form (TRACK 0) results are presented according to the critical check for given member with indication of SNiP clause number. result obtained (ACCEPTED – requirements are met.5 Member Selection and Code Check Both code checking and member selection options are available in SNiP 2. Refer to Section 2. “P” – tension). Three versions of output results are possible: suppressed – results according the critical strength condition (TRACK=0).6 of the Technical Reference Manual for general information on Member Selection. in which the most unfavorable combination of forces acts. standard) (SNiP). 734 — STAAD.2 Example of TRACK 1 output In extended form (TRACK 1) results are presented on the basis of all required by SNiP checks for given stress state. ======================================================================== MEMBER CROSS RESULT/ CRITICAL COND/ RATIO/ LOADING/ SECTION NO.650E+02 0. Inertia moment (second moment of area) (I).23-81* (Edition 1999) SECTION NO.5. Section area. Section characteristics: Length of member.000E+00 3. Section modulus (W). Results are presented in two columns.650E+02 0. Russian Codes . Elasticity modulus.Pro . FX MZ MY LOCATION ======================================================================== 1 I60 PASS SNiP. l l l l l l l l l l l l l l l l l l l Material characteristics: Steel. Net area.68 1 0.000E+00 -4.000E+00 -4. Moments.5. Design resistance.3 Example of a TRACK 2 output In advanced form (TRACK=2) in addition to tabled results supplementary information is presented.650E+02 0. Z and Y respectively. First moment of area (S).000E+00 3.5.68 1 0.15B.DISPL 0.000E+00 -4.18 0. Slenderness. Effective length.000E+00 1 I60 PASS SNiP.000E+00 15B.000E+00 15B. FX MZ MY LOCATION ======================================================================== 1 I60 PASS SNiP.5.18 0. Design forces: Longitudinal force. Shear force. Radius of gyration.Steel Design Per SNiP 2.36 1 0.000E+00 3. 00E+00 Shear force : 0. η-ETA.E-05 182.000E+00 -4.00E+00 500.094E-02 M Loading No. multiplication.56E-03= 162. “-“. FX MZ MY LOCATION ======================================================================== 1 I60 PASS SNiP.m) Member Length = 6.g. “/”.e. “SQRT”.m)SNiP II-23-81*/1998 Axial force : 0.000E-02 M Conventional notations assumed in presentation of results: “+”.E-04 Effective Length : 600.00E+00 0. raising to the second power (squared).E-02 CRITICAL CONDITIONS FOR EACH CLAUSE CHECK F.0E+00/ 1. . etc.E-06 173.).5.00E+00 DESIGN DATA (units -kN.”**”. ======================================================================== MEMBER CROSS RESULT/ CRITICAL COND/ RATIO/ LOADING/ SECTION NO. α-ALPHA.0E+03 ACTUAL SECTION DISPLACEMENT = 1.E+03 KPA SECTION PROPERTIES (units . subtraction.E+06 KPA Design Strength (Ry) = 240.E-03 354.E+00 RY*GAMAC= 240.38E-02 Net Area = 1.00E+00 Gross Area = 1.094E-02 M MAXIMUM MEMBER DEFLECTION = 1.E-07 Section modulus (W) : 256. and square root).(41) Q/(H*T)= 500.000E+00 1 I60 PASS SNiP.650E+02 0. φ-PHI.E-05 156.000E+00 MATERIAL DATA Steel =C245 Modulus of elasticity = 206. bending moments and shear forces in accordance with sign rules assumed in program STAAD. Check results in advanced form are presented with values of intermediate parameters by formulas in analytical and numerical expression with indication of SNiP clause.38E-02 z-axis y-axis Moment of inertia (I) : 768. division.E+00 0. γ -GAMAC.Signs “+” and “-“ indicate direction of acting longitudinal force. 1 ULTIMATE ALLOWABLE DEFLECTION VALUE = 3.E-02 600. β-BETA.1E+03 F.000E+00 3.E-02 Slenderness : 0.000E+00 -4.. c International Design Codes Manual — 735 .000E+00 3.18 0. “*”.0E-02/ 6.12E+00* 2. addition. Only Greek letters are changed by their names (e.(39) M/(C1*Wmin)=-465. their respective meanings (i.00E+00 z-axis y-axis Moments : -465.00E-01* 1..E-06 Radius of gyration (i) : 236.36 1 0.E-06 First moment of area (S) : 149.DISPL 0. Conventional notations of stresses. coefficients and characteristics of steel resistance comply with accepted in the SNiP standard.650E+02 0.20E-02= 694.68 1 0. Pro .736 — STAAD. Section 16 Singaporian Codes International Design Codes Manual — 737 . 738 — STAAD.Pro . Singaporean Codes . International Design Codes Manual — 739 .Pro is capable of performing concrete design based on the Singaporean code CP65 Code of Practice for Structural Use of Concrete.16A. Design of members per CP65 requires the STAAD Asia Design Codes SELECT Code Pack.Concrete Design per CP65 STAAD. Pro .740 — STAAD. Face of support location at end of beam. Column unbraced in either direction. CLEAR 20 mm Clearance of reinforcement measured from concrete surface to closest bar perimeter. Default values of commonly used parameters for conventional design practice have been chosen as the basis. its value stays at that specified number until it is specified again.0 Member length factor about local Y direction for column design. DEPTH YD EFACE 0.2 of the Technical Reference Manual. Table 16A. See section 5. BRACE 0.1 contains a complete list of available parameters with their default values. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process.1-Singaporean Concrete Design CP65 Parameters Parameter Name CODE Default Value Description Must be specified as CP65. in current units. This value default is as provided as YD in MEMBER PROPERTIES. 3.0 Note: Both SFACE & EFACE must be positive numbers. Note: Once a parameter is specified. Column braced in both directions 1. in current units.0 Bracing parameter for column design: 0.52. Column braced in only the local Z direction. Design Code to follow. Table 24. Depth of concrete member. International Design Codes Manual — 741 .16A.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design per the CP65 code. 2. ELY 1. Column braced in only the local Y direction. This is the way STAAD works for all codes. in current units. 0 Description Member length factor about local Z direction for column design. in current units. in current units (For slabs. it is for reinforcement in both directions) Yield Stress for secondary reinforcement a. Serviceability checks: 0.Pro . The upper limit is 23. 3. Perform serviceability check for beams as if they were continuous. Maximum required reinforcement bar size Acceptable bars are per MINMAIN above. in current units.Parameter Name ELZ Default Value 1. 2.0 SFACE 0.use MEMBER OFFSET for bending ) 742 — STAAD. 1. Concrete Yield Stress / cube strength. NSE CTION 12 SERV 0. Perform serviceability check for beams as if they were cantilever beams. (Only applicable for shear .0 Face of support location at start of beam. FC 4.0 ksi FYMAIN 60 ksi FYSEC 60 ksi MAX MAIN 50 mm MINMAIN 8 mm Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 16 20 25 32 40 50 MINSEC 8 mm Minimum secondary bar size a. Applicable to shear reinforcement in beams MMAG 1. Applicable to shear bars in beams. Perform serviceability check for beams as if they were simply supported. in current units Yield Stress for main reinforcement.0 Factor by which column design moments are magnified Number of equally-spaced sections to be considered in finding critical moment for beam design. No serviceability check performed. For beam gives min/max steel % and spacing. WIDTH ZD Width of concrete member.0 = Orthogonal reinforcement layout without considering torsional moment Mxy -slabs only -500 = Orthogonal reinforcement layout with Mxy used to calculate Wood & Armer moments for design. 2. Details of reinforcement at sections defined by the NSECTION parameter. Two special values are also considered: 0. For columns gives a detailed table of output with additional moments calculated. Beam design only. This value default is as provided as ZD in MEMBER PROPERTIES. Column design gives no detailed results. 1. in current units.0 Description Skew angle considered in Wood & Armer equations where A is the angle in degrees. International Design Codes Manual — 743 .Parameter Name SRA Default Value 0. Critical Moment will not be printed with beam design report.0 Controls level of detail in output: 0. TRACK 0. Pro .744 — STAAD. Section 17 South African Codes International Design Codes Manual — 745 . 746 — STAAD.Pro . Note: Once a parameter is specified. Table 17A. and torsion) and columns (axial load + biaxial bending).Concrete Design per SABS-0100-1 STAAD.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to SABS 0100-1.1 contains a complete list of available parameters with their default values. the program calculates the required reinforcement. Column unbraced in both Y and Z directions International Design Codes Manual — 747 .17A.1-South African Concrete Design SABS 0100-1 Parameters Parameter Name CODE Default Value Description - Must be specified as SABS0100.52. Column unbraced about local Z direction only 3. These parameters not only act as a method to input required data for code calculations but give the engineer control over the actual design process. Design Code to follow. shear. South African Codes . its value stays at that specified number until it is specified again.2 of the Technical Reference Manual. Table 17A. See section 5. Default values of commonly used parameters for conventional design practice have been chosen as the basis. Design can be performed for beams (flexure. BRACE 0. 1. 17A. Column braced in both directions. Given the width and depth (or diameter for circular columns) of a section.0 Column bracing: 0. Column braced about local Y direction only 2. This is the way STAAD works for all codes.Pro is capable of performing concrete design based on the South African code SABS0100-1 2000 Code of Practice for Structural Use of Concrete Part1: Design. Design of members per SABS-0100-1 requires the STAAD CAN/AUS/SA Design Codes SELECT Code Pack. Applicable to shear bars in beams Maximum required reinforcement bar size Acceptable bars are per MINMAIN above. Member length factor about local Y direction for column design. Minimum main reinforcement bar size Acceptable bar sizes: 6 8 10 12 16 20 25 28 32 36 40 50 60 Minimum secondary bar size a.Concrete Design per SABS-0100-1 Parameter Name CLB Default Value Description 20mm Clear Cover for outermost bottom reinforcement Clear Cover for outermost side reinforcement Clear Cover for outermost top reinforcement Depth of concrete member. South African Codes . in current units.Pro . in current units. Member length factor about local Z direction for column design. Yield Stress for main reinforcement.0 30N/mm 2 450 N/mm 2 450N/mm 2 FC FYMAIN FYSEC MAXMAIN 50mm MINMAIN 8mm MINSEC 8mm 748 — STAAD. Applicable to shear reinforcement in beams CLS 20mm CLT 20mm DEPTH YD ELY 1.0 ELZ 1. This value default is as provided as YD in MEMBER PROPERTIES.17A. Yield Stress for secondary reinforcement a. Concrete Yield Stress / cube strength. in current units. in current units. X 200. Critical Moment will not be printed with beam design report. the program will calculate them from YD and ZD. Note that area (AX) is not provided for these members.FLANGE 1000.0 List of design sag/hog moments and corresponding required steel area at each section of member WIDTH ZD Width of concrete member. Column design gives no detailed results. In the above input. the first set of members are rectangular (450mm depth x 300mm width) and the second set of members. with only depth and no width provided. The following example demonstrates the required input: UNIT MM MEMBER PROPERTIES *RECTANGULAR COLUMN 300MM WIDE X 450MM DEEP 1 3 TO 7 9 PRISM YD 450. will be assumed to be circular with 300mm diameter. the user may provide them along with YD and ZD.(DEEP) 14 PRISM YD 550. For beam gives min/max steel % and spacing. 2. in current units. Output of TRACK 1. This value default is as provided as ZD in MEMBER PROPERTIES. If shear area areas (AY & AZ ) are to be considered in analysis.Parameter Name TRACK Default Value Description 0. YB 350. 1.2 Member Dimensions Concrete members that are to be designed by STAAD must have certain section properties input under the MEMBER PROPERTIES command.0 Output detail 0. 17A. Finally a T section can be considered by using the third definition above.(YD-YB) * . *CIRCULAR COLUMN 300MM DIAMETER 11 13 PR YD 300. * T-SECTION . ZD 300.STEM 250(THICK) X 350. International Design Codes Manual — 749 . ZD 1000. For columns gives a detailed table of output with additional moments calculated. Also note that if moments of inertias are not provided. ZB 250. Shear design as per SABS 0100 clause 4.0 mm DESIGN LOAD SUMMARY (KN MET) --------------------------------------------------------------------------SECTION |FLEXURE (Maxm. If torsion is present.39 1 | 0.Pro .89 1 | -28.0 | 0. 4.00 0 | 2500.0 | 0.3.) LENGTH: 6000.70 1 -9.0 | 0.39 1 | 0.39 1 | -41. The total number of sections considered is thirteen.13 4.00 0 -9. For all types of beam action.89 1 | -28.0 | 56.39 1 | -55.39 1 750 — STAAD.13 4.00 0 | 3500.0 | 0.00 0 -9.0 | 28.00 0 -9. 4 D E S I G N R E S U L T S M30 Fe450 (Main) Fe450 (Sec.13 4.50 1 -9. From these values.5.3.39 1 | -27.89 1 | -28.39 1 | -69.89 1 | -28.89 1 | -28.77 1 -9.89 1 | -28.57 1 -9.89 1 | -28.89 1 | -28.89 1 | -28.0 | 42.00 0 -9.13 4.13 4.00 0 | 1000.37 1 -9.0 mm SIZE: 715.0 | 84. Sagging/Hogging moments)| SHEAR (in mm) | MZ Load Case MX Load Case | VY P Load Case --------------------------------------------------------------------------0.3.0 | 0.89 1 | -28.39 1 | 0.39 1 | 0.13 4.0 | 14.00 0 | 500.13 4. Torsional reinforcement is separately reported.4 has been followed and the procedure includes computation of critical shear values.0 | 0.Concrete Design per SABS-0100-1 17A.0 | 70.13 4. A TRACK 2 design output is presented below. stirrup sizes are calculated with proper spacing.84 1 | 5000.13 4. all active beam loadings are scanned to create moment and shear envelopes and locate the critical sections.00 0 | 1500.3 Beam Design Beam design includes flexure.00 0 -9.39 1 | 0.97 1 | 6000. the required positive and negative bar pattern is developed.3.00 0 | 3000.77 1 | 4500.00 0 -9.0 mm X 380.13 4.89 1 | -28.64 1 -9.17A.0 | 0.89 1 | -28. shear and torsion. South African Codes . ============================================================================ B E A M N O.0 mm COVER: 40.39 1 | 0.13 4.13 4.39 1 | 0.89 1 | -28. the program will also consider the provisions of SABS 0100 clause 4. From the critical moment values.00 0 | 2000.70 1 | 4000.13 4.39 1 | -13.90 1 | 5500.4.43 1 -9. Design for flexure is carried out as per clause no. column size and critical load case.0 | 543. AREA FOR FLEXURE DESIGN (Sq.04 1 | ---------------------------------------------------------------------------SUMMARY OF REINF.0 mm X 380.40/ 549. This causes slightly conservative results in certain cases.24( 6-10í )| 8í @ 115 mm 1500.40/ 549.21/ 392.60( 6-12í )| 543.| -84.70( 5-10í )| 543.0 | 353.40( 4-12í )| 543.6 About Z 0.83/ 678.0 | 543.86( 9-10í )| 8í @ 115 mm 500.78( 7-10í )| 353.0 | 543.1.0 | 561. | (2 legged) ---------------------------------------------------------------------------0.0 | 353.0 | 543. TRACK 0.91/ 452.00 About Y 0.78( 7-10í )| 567. For rectangular and square sections.70( 5-10í )| 543.0 would merely give the bar configuration.0 | 543. Bracing conditions are controlled by using the BRACE parameter.78( 7-10í )| 680./Provided reinf.40/ 549. The loading which produces maximum reinforcement is called the critical load and is displayed.40/ 549.40/ 549.0 | 353.71/ 706.78( 7-10í )| 8í @ 115 mm 4500.21/ 392.40/ 549. The program will then decide whether or not the column is short or slender and whether it requires additional moment calculations.78( 7-10í )| 8í @ 115 mm 6000.78( 7-10í )| 8í @ 115 mm 5500.70( 5-10í )| 8í @ 115 mm 3000.00 International Design Codes Manual — 751 . Column design is done for square.21/ 392. with the user having control on the effective length in each direction by using the ELZ and ELY parameters as described in table 12A.70( 5-10í )| 8í @ 115 mm 2000.) LENGTH: 3000. rectangular and circular sections./Provided reinf.0 mm CROSS SECTION: 715. The requirements of SABS 0100-1 clause 4.0 mm COVER: 40.78( 7-10í )| 8í @ 115 mm ---------------------------------------------------------------------------TORSION REINFORCEMENT : Not required 17A.70( 5-10í )| 543.40/ 549.18( 3-16í )| 8í @ 115 mm 1000.40/ 549.21/ 392.40/ 549.40/ 549.87/ 565.4. 1 D E S I G N R E S U L T S M30 Fe450 (Main) Fe450 (Sec.mm) ---------------------------------------------------------------------------SECTION | TOP | BOTTOM | STIRRUPS (in mm) | Reqd. the reinforcement is always assumed to be arranged symmetrically. the detailed output below is obtained.75/ 603.50( 5-12í )| 543.40/ 549.40/ 549.70( 5-10í )| 8í @ 115 mm 3500. ============================================================================ C O L U M N N O. For biaxial bending.0.70( 5-10í )| 8í @ 115 mm 2500.78( 7-10í )| 8í @ 115 mm 4000.0 | 674.78( 7-10í )| 8í @ 115 mm 5000.0 mm ** GUIDING LOAD CASE: 1 END JOINT: 2 SHORT COLUMN DESIGN FORCES (KNS-MET) ----------------------DESIGN AXIAL FORCE (Pu) INITIAL MOMENTS : : -14.78( 7-10í )| 353.0 | 448.79/ 471.0 | 543.21/ 392.7 are followed.40/ 549.78( 7-10í )| 353. | Reqd.21/ 392.78( 7-10í )| 353.78( 7-10í )| 454.7. the recommendations of 4. All active loadings are tested to calculate reinforcement.21/ 392. Using parameter TRACK 1.4 Column Design Columns are designed for axial force and biaxial bending at the ends. required steel area and percentage.0 | 543.4 of the code are considered. 89 4.mm. South African Codes .mm.41 REQD.Concrete Design per SABS-0100-1 MOMENTS DUE TO MINIMUM ECC.99 Sq.17A.17%. rectangular ties @ 140 mm c/c SECTION CAPACITY BASED ON REINFORCEMENT REQUIRED (KNS-MET) ---------------------------------------------------------Puz : 25. CONCRETE AREA: 1213. STEEL AREA : 26.) (Equally Distributed) TIE REINFORCEMENT : Provide 8 mm dia.17 9. : 0.Pro .mm.00 0.61 Sq. REQD.29 SLENDERNESS RATIOS : 7.22 Muy1 : 51.28 0. (0. 452.20 ADDITION MOMENTS (Maddz and Maddy) : 0.00 TOTAL DESIGN MOMENTS : 45.48 ============================================================================ 752 — STAAD.50 Muz1 : 45.40 Sq. MAIN REINFORCEMENT : Provide 4 .12 dia. 7 the STAAD Technical Reference Manual. The code checking portion of the program checks whether code requirements for each selected section are met and identifies the governing criteria. The user is allowed complete flexibility in providing loading specifications and using appropriate load factors to create necessary loading situations.17B. stability and serviceability. Appropriate load and resistance factors are used so that a uniform reliability is achieved for all steel structures under various loading conditions and at the same time the chances of limits being surpassed are acceptably remote. The primary considerations in ultimate limit state design are strength and stability. South African Codes .1 General The design philosophy embodied in this specification is based on the concept of limit state design. the most economic section is selected on the basis of the least weight criteria as augmented by the designer in specification of allowable member depths. Member properties may also be specified using the User Table facility.ultimate and serviceability.2 Analysis Methodology Elastic analysis method is used to obtain the forces and moments for design.37 of the Technical Reference Manual for additional information. while that in serviceability is deflection. Depending upon the analysis requirements. A detailed description of the design process along with its underlying concepts and assumptions is available in the specification document. Analysis is done for the primary and combination loading conditions provided by the user. 17B. Refer to Section 5.4 Built-in Steel Section Library A steel section library consisting of South African Standards shapes is available for member property specification.Steel Design Per SAB Standard SAB0162-1:1993 17B. 17B. refer to Section 1. The next section describes the syntax of commands used to assign properties from the built-in steel table. desired section type. Two major categories of limit-state are recognized . International Design Codes Manual — 753 . Structures are designed and proportioned taking into consideration the limit states at which they would become unfit for their intended use. In the STAAD implementation. Accordingly. The next few sections describe the salient features of the STAAD implementation of SAB0162-1: 1993. regular stiffness analysis or P-Delta analysis may be specified. the steel section library available in STAAD may be used. or other such parameters. Dynamic analysis may also be performed and the results combined with static analysis results. 17B.3 Member Property Specifications For specification of member properties. members are proportioned to resist the design loads without exceeding the limit states of strength. For more information on these facilities. shapes. 18 TO 20 TABLE ST 152X37UC 17B. Refer to Section 1. are specified by preceding the section designation by the letter D.4 Channel Sections (C & MC shapes) C and MC shapes are designated as shown in the following example.4.Pro .4.1 I Shapes The following example illustrates the specification of I. the properties are also used for member design.2 of the Technical Reference Manual for additional information.5 Double Channels Back to back double channels.01 unit length in between should be specified as: 100 TO 150 TABLE D 140X60X16C SP 0.4.17B.4.4. These properties are stored in a database file. 3 TABLE ST 127X64X15C 17B.2 H shapes Designation of H shapes in STAAD is as follows. 17B. Since the shear areas are built into these tables. shear deformation is always considered during the analysis of these members. If called for. a back to back double channel section PFC140X60 without spacing in between should be specified as: 100 TO 150 TABLE D PFC140X60 A back-to-back double channel section 140X60X16C with spacing 0. 100 TO 150 TABLE ST 720X200PG 17B.Steel Design Per SAB Standard SAB0162-1:1993 The following information is provided for use when the built-in steel tables are to be referenced for member property specification.7. South African Codes . with or without spacing between them.01 754 — STAAD. For example. 1 TO 15 TABLE ST IPE-AA100 17B. For example.3 PG shapes Designation of PG shapes in STAAD is as follows. 8 Tees Tee sections obtained by cutting W sections may be specified by using the T specification instead of ST before the name of the W shape. 100 TO 150 TABLE RA 45X45X3L The local axis systems for STANDARD and REVERSE angles are shown in Fig. In this specification.4. The spacing should always be provided in the current length unit. Refer to the following example for details. the local z-axis (see Fig. 100 TO 150 TABLE LD 50X50X3L 3 TABLE LD 40X40X5L SP 0. For example: 100 TO 150 TABLE T IPE-AA180 will describe a T section cut from a IPE-AA180 section.4. 100 TO 150 TABLE ST 70X70X8L Note that the above specification is for “standard” angles. International Design Codes Manual — 755 .6 Angles To specify angles. 17B. 17B.6 in the Technical Reference Manual) corresponds to the Y’-Y’ axis shown in the CSA table. Thus. 2. the specification ST should be substituted with LD (for long leg back-to-back) or SD (short leg back-to-back). 2. A reverse angle may be specified by substituting the word ST with the word RA. For equal angles. either SD or LD will serve the purpose. 17B.01 length units.6 of the STAAD Technical Reference manual. the reverse angle designation facility has been provided.01 The second example above describes a double angle section consisting of 40X40X5 angles with a spacing of 0.4.Note: The specification SP after the section designation is used for providing the spacing. the letter L succeeds the angle name. The following examples illustrate angle specifications. Spacing between angles may be provided by using the word SP followed by the value of spacing (in current length unit) after section designation. To specify angles in accordance with this convention.7 Double Angles To specify double angles. Another common practice of specifying angles assumes the local y-axis to correspond to the Y’-Y’ axis. a 70X70 angle with a 25mm thickness is designated as 70X70X8L. width of 100mm. any tube section may be specified by using the DT(for depth).4.0CHS In addition to sections listed in the SAB tables. 100 TO 150 TABLE ST TUB60X30X2.Steel Design Per SAB Standard SAB0162-1:1993 17B. 17B. South African Codes . Those sections listed in the SAB tables may be specified as follows. and a wall thickness of 3mm. For example: 100 TO 150 TABLE ST PIPE OD 50 ID 48 will describe a pipe with an outside diameter of 50 length units and inside diameter of 48 length units.17B. A sample input file to demonstrate usage of South African shapes: STAAD PLANE START JOB INFORMATION ENGINEER DATE 30-MAR-05 END JOB INFORMATION 756 — STAAD. circular hollow sections may be specified by using the OD (outside diameter) and ID (inside diameter) specifications. width and thickness must be provided in current length unit. WT(for width). For example: 100 TO 150 TABLE ST TUBE TH 3 WT 100 DT 50 will describe a tube with a depth of 50mm.Pro . Note that the values of depth. and TH(for thickness) specifications.5 In addition.9 Rectangular Hollow Sections These sections may be specified in two possible ways.4.10 Circular Hollow Sections Sections listed in the SAB tables may be provided as follows: 100 TO 150 TABLE ST PIP34X3. Note that the values of outside and inside diameters must be provided in terms of current length unit. 13 8 13. 22 10 11.4 0. 3 2 6.0CHS 21 TABLE ST PIPE OD 0. local buckling becomes an important criterion. 20 7 9. 6 9 6 0.5 11.02 WT 100 DT 50 20 TABLE ST PIP48X2. 10 14 16. 14 3 12. 9 12 14.5 ID 0.5 0.5 0.5 11. 12 13 15. 12 1. 2 9 0 0. 11 15 16.5 0.5 13. or slender element (Class 4) sections depending upon their local buckling characteristics (See Clause 11.2 and Table 1 of SAB0162-1:1993). 8 9 10. 18 10 15. 4 6 8.3 0. The design procedures are different International Design Codes Manual — 757 .2 0. noncompact (Class 3). Steel sections are classified as plastic (Class 1).UNIT METER KN JOINT COORDINATES 1 0 0 0.1 15 TABLE SD 25X25X5L SP 0. 7 0 10. 16 11 14. 19 10 13. 4 3 6 0. 16 4.48 PRINT MEMBER PROPERTIES FINISH 17B.25 10. MEMBER INCIDENCES 1 1 3. 21 9 11. This classification is a function of the geometric properties of the section.5 Section Classification The SAB specification allows inelastic deformation of section elements.3 0. 10 6. Thus. 5 3 4. MEMBER PROPERTY SAFRICAN 1 TABLE ST IPE-AA100 2 TABLE T IPE120 3 TABLE ST 152X23UC 4 TABLE T 152X23UC 5 TABLE ST 812X200PG 6 TABLE T 812X200PG 7 TABLE ST 178X54X15C 8 TABLE D 178X54X15C 9 TABLE D 178X54X15C SP 0. 15 6 12.1 16 TABLE ST TUB40X2.5 0. 15 9 14. compact (Class 2). 8 7 12.5SHS 17 TABLE ST TUBE TH 0 WT 0 DT 50 18 TABLE ST TUBE TH 0.1 10 TABLE ST 25X25X5L 11 TABLE RA 25X25X5L 12 TABLE LD 25X25X5L 13 TABLE SD 25X25X5L 14 TABLE LD 25X25X5L SP 0. 3 0 6 0. 14 9 12. 23 8 10.5 10. 6 4 5.4 0.75 10. 17 11 15. 9 2. 13 7. 11 4. 2 3 7. 7 5 6. 5 6 6 0.5 0. 2 Axial Compression The compressive resistance of columns is determined based on Clause 13. and NSF are applicable for these calculations. LY. The reason for this is that the South African code doesn’t provide any clear guidelines for calculating this value. KZ. LY. All the members are checked against allowable slenderness ratio as per Cl. The equations presented in this section of the code assume that the compressive resistance is a function of the compressive strength of the gross section (Gross section Area times the Yield Strength) as well as the slenderness factor (KL/r ratios). Some of the aspects of the axial compression capacity calculations are: 1. The effective length for the calculation of compression resistance may be provided through the use of the parameters KX.17B.6. 17B. Tees and Double angles. or 3 sections only. For single angles. Design is performed for sections that fall into the category of Class 1. FU.3 of the code. While computing the general column flexural buckling capacity of sections with axial 758 — STAAD. The parameters KY.2. KY. South African Codes .3.10. Explained here is the procedure adopted in STAAD for calculating the member resistances. 3.Pro .1). KZ. Class 4 sections are not designed by STAAD. STAAD determines the section classification for the standard shapes and user specified shapes. and LZ are applicable for this.13. single angles. Note that the program automatically takes into consideration appropriate resistance factors to calculate member resistances. cross-sectional properties. 17B. KZ.6 Member Resistances The member resistances are calculated in STAAD according to the procedures outlined in section 13 of the specification.1 Axial Parameters FYLD. and LZ (see Table 13B. These depend on several factors such as members’ unsupported lengths. Parameters KX and LX may be used to provide the effective length factor and effective length value for flexural-torsional buckling. The axial compression capacity is also calculated by taking flexural-torsional buckling into account.6. and LZ are applicable for this. the axial compression capacities are calculated by using Cl.1 using the slenderness ratios for the local Y-Y and Z-Z axis. LY. the axial compression capacity in general column flexural buckling is calculated from Cl. 2. The parameters KY. LX. slenderness factors. 4.Steel Design Per SAB Standard SAB0162-1:1993 depending on the section class.2 of SAB0162-1: 1993.as torsional flexural buckling is not critical. For frame members not subjected to any bending. Flexural-torsional buckling capacity is computed for single channels. 17B.13. But for KL/r ratio exceeding 50.3. and for truss members. asymmetric or cruciform sections are checked as to whether torsional-flexural buckling is critical. unsupported width to thickness ratios and so on. 1). The weak axis bending capacity of all sections except single angles is calculated as: For Class 1 & 2 sections Phi*Py*Fy For Class 3 sections Phi*Sy*Fy Where: Phi = Resistance factor = 0. For example. 17B. The equations of Clause 13. 3.1(c) are applied. the moment resistance is computed from Clause 13.5 of the code. the member is considered to have FAILed under the loading condition.8 of the code provides the equations for this purpose. page 31. In these equations.4 Axial compression and bending The member strength for sections subjected to axial compression and uniaxial or biaxial bending is obtained through the use of interaction equations. etc.6 of the code are used to arrive at the moment of resistance of laterally unsupported members.8.1(b).6(b).3 Bending The laterally unsupported length of the compression flange for the purpose of computing the factored moment resistance is specified in STAAD with the help of the parameter UNL.0 or the allowable value provided using the RATIO parameter (see Table 17B. 13.8. that a rational method.) 17B.1(a). as the South African code doesn’t provide any clear guidelines for calculating this value. If UNL is greater than or equal to one-tenth the member length.9 Py = Plastic section modulus about the local Y axis Sy = Elastic section modulus about the local Y axis Fy = Yield stress of steel 2. Clause 13. Single angles sections are not designed by STAAD.1(a).6.compression + bending. the additional bending caused by the action of the axial load is accounted for by using amplification factors. For calculating the bending capacity about the Z-Z axis of singly symmetric shapes such as Tees and Double angles. its value is used as the laterally unsupported length. International Design Codes Manual — 759 . In this case. If UNL is less than one tenth the member length (member length is the distance between the joints of the member). Some of the aspects of the bending capacity calculations are: 1. SAB0162-1: 1993 stipulates in Clause 13. K=1 for 13. the special provisions of 13. Lambda = 0 for 13.8.8.8. If the summation of the left hand side of these equations exceeds 1.6.1(b) and 13. the member is treated as being continuously laterally supported. 3.7 Design Parameters The design parameters outlined in table below may be used to control the design procedure.4.5 Axial tension and bending Members subjected to axial tension and bending are also designed using interaction equations. Table 17B. The default parameter values have been selected such that they are frequently used numbers for conventional design. Note: Once a parameter is specified.4 of the code. Users may bypass this limitation by specifying a value of 2.13.0 or the allowable value provided using the RATIO parameter (see Table 17B.48.17B.1 Equal to 0. Once this is obtained.5.Value of Omega_2 (C1.1-South African Steel Design Parameters Parameter Name CODE Default Value Must be specified SAB0162.0 and less than 2.0 for the MAIN parameter. 17B.6 Shear The shear resistance of the cross section is determined using the equations of Clause 13. Clause 13. page 29 of SABS 0162-1:1993).1 of the Technical Reference Manual. This is the way STAAD works for all codes.0 Greater than 0. 17B.6.6.0: Calculate Omega_2 760 — STAAD.Perform design at ends and 1/12th section locations alo CB 1.Steel Design Per SAB Standard SAB0162-1:1993 17B. Design Code to follow. some or all of these parameter values may be changed to exactly model the physical structure. The actual RATIO is determined as the value of the left hand side of the critical equation. Depending on the particular design requirements.Pro . See section 5. the section is considered to have failed under shear.1. the ratio of the shear force acting on the cross section to the shear resistance of the section is calculated. South African Codes . BEAM 0 0 . These parameters communicate design decisions from the engineer to the program and thus allow the engineer to control the design process to suit an application's specific needs. its value stays at that specified number until it is specified again.Perform design at ends and those locations specified Description 1 . If any of the ratios (for both local Y & Z axes) exceed 1.9 of the code is used to perform these checks.1). The code also requires that the slenderness ratio of the web be within a certain limit (See Cl. Checks for safety in shear are performed only if this value is within the allowable limit. No sideway about local Y-axis. 1 .0 1.Calculate Omega-1 for local Z axis DFF DJ1 0 0 Default is 0 indicating that deflection check is not perfor Start node of physical member for determining deflected set along with DFF parameter End node of physical member for determining deflected set along with DFF parameter Maximum allowable depth Minimum required depth Yield strength of steel Ultimate strength of steel K value for flexural torsional buckling K value in local Y-axis.0 1.Calculate Omega-1 for local Y axis Description CMZ 1.0 1.Do not calculate Omega-1 for local Y axis. 2 .Sideway about local Y-axis. 2 .0 Member length Member length Member length 0 NSF RATIO 1. 1 . International Design Codes Manual — 761 .Do not calculate Omega-1 for local Z axis.0 1 . usually major axis Length for flexural torsional buckling Length in local Y axis for slenderness value KL/r Length in local Z axis for slenderness value KL/r Flag for controlling slenderness check 0 .Parameter Name CMY 1.For Do not check for slenderness DJ2 0 DMAX DMIN FYLD FU KT KY KZ LT LY LZ MAIN 1000 0 300Mpa 345Mpa 1.0 Default Value 1 .For Check for slenderness.0 Net section factor for tension members Permissible ratio of applied load to section capacity Used in altering the RHS of critical interaction equations SSY 0 Sidesway parameter 0 . usually minor axis K value in local Z-axis. governing load case. the critical condition. South African Codes . Print the design output at the intermediate detail 2. The adequacy is checked as per the SAB0162-1: 1993 requirements. Description TRACK 0 Track parameter 0.No sideway about local Z-axis. The code checking output labels the members as PASSed or FAILed. design will be based on member start and end forces only.2 of the Technical Reference Manual for details the specification of the Code Checking command.8 Code Checking The purpose of code checking is to determine whether the current section properties of the members are adequate to carry the forces obtained from the most recent analysis. 1 . Refer to Section 2. 17B. location (distance from the start joint) and magnitudes of the governing forces and moments are also printed. Refer to Section 5.8. Print the design output at the minimum detail le 1. Code checking is done using forces and moments at specified sections of the members.48. Print the design output at maximum detail level UNB UNT Member Length Member Length Unsupported length in bending compression of bottom f Unsupported length in bending compression of top flang 17B. When no section locations are specified and the BEAM parameter is set to zero. Using the TRACK parameter can control the extent of detail of the output.1 Example Sample input data for South African Code Design PARAMETER CODE SAB0162 MAIN 1 ALL LY 4 MEMB 1 LZ 4 MEMB 1 UNL 4 MEMB 1 CB 0 MEMB 1 TO 23 762 — STAAD.Steel Design Per SAB Standard SAB0162-1:1993 Parameter Name SSZ 0 Default Value Sidesway parameter 0 .17B.Sideway about local Z-axis. If the BEAM parameter for a member is set to 1 (which is also its default value). In addition. moments are calculated at every twelfth point along the beam.Pro .5 of the Technical Reference Manual for general information on Code Checking. 0.CMZ MEMB 2 1 TO 23 CMY MEMB 2 1 TO 23 SSY 0 MEMB 1 TO 23 SSZ 0 MEMB 1 TO 23 FU 450000 MEMB 1 TO 23 BEAM 1 ALL NSF 0. which governed the design. 17B.3 of the Technical Reference Manual for details the specification of the Member Selection command. a member specified initially as a channel will have a channel selected for it. Selection of members whose properties are originally provided from a user table will be limited to sections in the user table.6 of the Technical Reference Manual for general information on Member Selection.48.PRO CODE CHECKING (SOUTHAFRICAN STEEL/SAB-0162-01(1993)) ************************************** ALL UNITS ARE . Member selection cannot be performed on members listed as PRISMATIC. Refer to Section 2.0 ALL TRACK 2 ALL FYLD 300000 1 TO 23 CHECK CODE ALL FINISH 17B. If the TRACK parameter is set to 1. The section selected will be of the same type as that specified initially.2 MEMB 3 4 RATIO 1.9 Member Selection The member selection process involves determination of the least weight member that PASSes the code checking procedure based on the forces and moments of the most recent analysis.85 ALL KY 1. Refer to Section 5. the output will be displayed as follows: ************************************** STAAD. The term CRITICAL COND refers to the section of the SAB0162-1: 1993 specification.KNS MEMBER TABLE LOADING/ LOCATION MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ FX MY RATIO/ MZ International Design Codes Manual — 763 .10 Tabulated Results of Steel Design Results of code checking and member selection are presented in a tabular format. For example. 50 VR= 642. ************************************** STAAD.PRO CODE CHECKING (SOUTHAFRICAN STEEL/SAB-0162-01(1993)) ************************************** ALL UNITS ARE .0 parameter is as follows. Output Term MRZ MRY CR TR VR Description Factored moment of resistance in z direction Factored moment of resistance in y direction Factored compressive resistance for column Factored tensile capacity Factored shear resistance Further details can be obtained by setting TRACK to 2.543 1 0.00 0.00E+02 MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ FX MY RATIO/ MZ 764 — STAAD. Following is a description of some of the items printed out.90 | | MRZ= 353.00 | |--------------------------------------------------------------------| Factored member resistances will be printed out.0.Steel Design Per SAB Standard SAB0162-1:1993 ======================================================================= 1 ST 406X67UB (SOUTHAFRICAN SECTIONS) PASS SAB-13.8 0. A typical output of track 2. South African Codes .KNS MEMBER TABLE LOADING/ LOCATION ======================================================================= 1 ST 406X67UB (SOUTHAFRICAN SECTIONS) PASS SAB-13.08 |--------------------------------------------------------------------| | FACTORED RESISTANCES FOR MEMBER1 UNIT .00 -191.90 4.21 TR= 2308.27 MRY= 63.17B.90 4.00 0.00 -191.543 1 0.99 | | CR= 453.55E+01 MEMBER LENGTH = 7.KN.8 0.M PHI = 0.08 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 8.Pro . 19E+03 1.308E+03 COMPRESSIVE CAPACITY = 4.075E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 85.1 Verification Problem No.11.399E+01 MRZ = 3. Output Term CRY CRZ CTORFLX TENSILE CAPACITY FACTORED MOMENT RESISTANCE FACTORED SHEAR RESISTANCE Description Factored compressive resistance for column buckling about the local y axis Factored compressive resistance for column buckling about the local z axis Factored compressive resistance against torsional flexural buckling Factored tensile capacity MRY = Factored moment of resistance in y direction MRZ = Factored moment of resistance in z direction VRY = Factored shear resistance in y direction VRZ = Factored shear resistance in z direction COMPRESSIVE CAPACITY Factored compressive capacity 17B.532E+02 CRZ = 2.00 OMEGA-1 (Z-AXIS) = 1. Column is braced at its ends for both axes. 17B.36E+03 SZ = SY = 1.75 SHEAR FORCE (KNS) : Y AXIS = -6.016E+03 CTORFLX = 4.532E+02 TENSILE CAPACITY = 2.11 Verification Problems In the next few pages are included three verification examples for reference purposes.0 FU = 345.33E+01 Following is a description of some of the items printed out.305E+01 Z AXIS = 0. International Design Codes Manual — 765 .000 KL/RY = 175.514 KL/RZ = 41.000 OMEGA-1 (Y-AXIS) = 1.IZ = IY = 2.532E+02 FACTORED MOMENT RESISTANCE : MRY = 6.M) --------------------------------CRY = 4.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 4.533E+02 FACTORED SHEAR RESISTANCE : VRY = 6.00 OMEGA-2 = 1.43E+04 1.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 4.522 ALLOWABLE KL/R = 300.37E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.35E+03 2. 1 Determine the capacity of a South African I-section column in axial compression per South African steel design code (SAB:0162-1(1993)) .52E+02 PZ = PY = 1.KN.420E+02 VRZ = 6.0 SECTION CAPACITIES (UNIT . 03 TYPE STEEL STRENGTH FY 248210 FU 399894 RY 1. Shades Technical publication Given FYLD = 300 Mpa Length = 6000 mm Comparison Table 17B. MEMBER PROPERTY SAFRICAN 1 TABLE ST 356X67UB DEFINE MATERIAL START ISOTROPIC STEEL E 1. Structural Steel Design to SAB:0162-1(1993)(Limit state Design) by Greg Parrott.8191 ALPHA 6E-006 DAMP 0.3 DENSITY 76.5 RT 1.4.Pro .3.18.1 comparison Criteria Axial Compressive Strength (kN) Reference STAAD.516 1.Steel Design Per SAB Standard SAB0162-1:1993 Reference Example 4.17B. 1st edition. page 4.1. 2 0 6 0.516 none Input File STAAD PLANE START JOB INFORMATION ENGINEER DATE END JOB INFORMATION UNIT METER KN JOINT COORDINATES 1 0 0 0.2-SABS 0162-1:1993 Verification problem no.99947E+008 POISSON 0. South African Codes .2 END DEFINE MATERIAL 766 — STAAD.Pro Difference 1. MEMBER INCIDENCES 1 1 2. 07E+03 IY = 1.KN.55E+01 IZ = 1.989 1 1500.00 0.43E+02 6.95E+04 SZ = 1.M) --------------------------------MEMBER LENGTH = PZ = 1.00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 8.00 0.KNS MEMBER TABLE MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST 356X67UB (SOUTHAFRICAN SECTIONS) PASS COMPRESSION 0.85 ALL TRACK 2 ALL FYLD 300000 ALL CHECK CODE ALL FINISH Output (SOUTHAFRICAN STEEL/SAB-0162-01(1993)) ************************************** ALL UNITS ARE .36E+03 SY = 1.0 FU = 345.57E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.00E+02 International Design Codes Manual — 767 .00 0.0 SECTION CAPACITIES (UNIT .UNIT MMS KN CONSTANTS MATERIAL STEEL ALL UNIT METER KN SUPPORTS 1 FIXED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 JOINT LOAD 2 FY -1500 PERFORM ANALYSIS PARAMETER 1 CODE SABS0162 LZ 6 ALL LY 3 ALL FU 450000 ALL BEAM 1 ALL NSF 0.21E+03 PY = 2. 991E+02 FACTORED SHEAR RESISTANCE : VRY = 5.12.220 KL/RZ = 39.12 Verification Problem No.12.00 OMEGA-2 = 1.17B.850 KL/RY = 75. 2 Determine the capacity of a South African I-section beam in bending per South African steel design code (SAB:0162-1(1993)).5.000 OMEGA-1 (Y-AXIS) = 1.37.00 OMEGA-1 (Z-AXIS) = 1. Shades Technical publication 17B.516E+03 FACTORED MOMENT RESISTANCE : MRY = 6.730 ALLOWABLE KL/R = 200.000E+00 Z AXIS = 0.Steel Design Per SAB Standard SAB0162-1:1993 CRY = 1.Pro Difference 353.561E+01 MRZ = 1.038E+03 CTORFLX = 1.3-SAB 0162 -1:1993 Verification Problem 2 comparison Criteria Major Axis Bending Resistance (kN) Reference STAAD.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 6.12. 2 10 0 0.12.903E+02 VRZ = 6. 1st edition. The beam has torsional and simple lateral rotational restraint at the supports. 3 7 0 0 768 — STAAD.3 none 17B.461E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 0.516E+03 CRZ = 2. South African Codes . and the applied point load provides effective lateral restraint at the point of application is braced at its ends for both axes.2 Given FYLD = 300 Mpa 17B. page 4.4 Input File STAAD PLANE START JOB INFORMATION ENGINEER DATE END JOB INFORMATION UNIT METER KN JOINT COORDINATES 1 0 0 0. Structural Steel Design to SAB:0162-1(1993)(Limit state Design) by Greg Parrott.65E+01 17B.4 353.1 Reference Example 4.00 SHEAR FORCE (KNS) : Y AXIS = 0. 17B.Pro .918E+03 COMPRESSIVE CAPACITY = 1.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 3.3 Comparison Table 17B.516E+03 TENSILE CAPACITY = 1. 2 3 2 MEMBER PROPERTY SAFRICAN 1 2 TABLE ST 406X67UB DEFINE MATERIAL START ISOTROPIC MATERIAL1 E 2.MEMBER INCIDENCES 1 1 3.00E+008 POISSON 3 DENSITY 977 ISOTROPIC STEEL E 2.00E+008 POISSON 3 DENSITY 8195 ALPHA 2E-005 DAMP 03 END DEFINE MATERIAL UNIT MMS KN CONSTANTS MATERIAL STEEL MEMB 1 2 UNIT METER KN SUPPORTS 1 3 PINNED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 MEMBER LOAD 1 CON GY -104 4 1 UNI GY -4 2 UNI GY -2 PERFORM ANALYSIS PARAMETER CODE SABS0162 CB 0 ALL UNL 4 MEMB 1 FU 450000 ALL BEAM 1 ALL NSF 85 ALL FYLD 300000 ALL TRACK 2 ALL CHECK CODE MEMB 1 FINISH International Design Codes Manual — 769 . 522 ALLOWABLE KL/R = 300. Structural Steel Design to SAB:0162-1(1993)(Limit state Design) by Greg Parrott.54.00 OMEGA-1 (Z-AXIS) = 1.543 1 0.1 Reference Example 4.90 4.33E+01 17B.13 Verification Problem No.00 OMEGA-2 = 1.37E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.6.5.5 Output ************************************** STAAD.532E+02 FACTORED MOMENT RESISTANCE : MRY = 6. South African Codes .00E+02 IZ = 2.2 Given FYLD = 300 Mpa 770 — STAAD.13.55E+01 MEMBER LENGTH = 7. 3 Determine the elastic shear capacity per South African steel design code (SAB:0162-1(1993)) of a South African I-section which is simply supported over the span of 8 m.533E+02 FACTORED SHEAR RESISTANCE : VRY = 6. 1st edition.36E+03 SY = 1.8 0.00 0.Steel Design Per SAB Standard SAB0162-1:1993 17B.399E+01 MRZ = 3. page 4.000 KL/RY = 175.KN.17B.35E+03 IY = 1.12.43E+04 SZ = 1.016E+03 CTORFLX = 4.19E+03 PZ = 1.305E+01 Z AXIS = 0.514 KL/RZ = 41.PRO CODE CHECKING (SOUTHAFRICAN STEEL/SAB-0162-01(1993)) ************************************** ALL UNITS ARE .0 SECTION CAPACITIES (UNIT .KNS MEMBER TABLE MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST 406X67UB (SOUTHAFRICAN SECTIONS) PASS SAB-13.13.532E+02 TENSILE CAPACITY = 2. 17B.0 FU = 345.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 4.532E+02 CRZ = 2.08 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 8.52E+02 PY = 2.420E+02 VRZ = 6.00 -191.M) --------------------------------CRY = 4.75 SHEAR FORCE (KNS) : Y AXIS = -6.308E+03 COMPRESSIVE CAPACITY = 4.000 OMEGA-1 (Y-AXIS) = 1. Shades Technical publication 17B.Pro .000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 4.075E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 85. 1 STAAD.1 Difference none 17B.3 Comparison Table 17B. 2 8 0 0 MEMBER INCIDENCES 1 1 2 MEMBER PROPERTY SAFRICAN 1 TABLE ST 457X67UB DEFINE MATERIAL START ISOTROPIC MATERIAL1 E 2E+008 POISSON 3 DENSITY 977 ISOTROPIC STEEL E 2E+008 POISSON 3 DENSITY 8195 ALPHA 2E-005 DAMP 03 END DEFINE MATERIAL UNIT MMS KN CONSTANTS MATERIAL STEEL MEMB 1 UNIT METER KN SUPPORTS 1 2 PINNED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 MEMBER LOAD International Design Codes Manual — 771 .Pro 687.17B.13.13.4-SAB 0162-1:1993 Verification Problem 3 comparison Criteria Shear Capacity (kN) Reference 687.4 Input File STAAD PLANE START JOB INFORMATION ENGINEER DATE END JOB INFORMATION UNIT METER KN JOINT COORDINATES 1 0 0 0. 00 OMEGA-2 = 1.738E+02 CRZ = 1.000 UNSUPPORTED LENGTH OF THE COMPRESSION FLANGE (M) = 8.KN.47E+03 IY = 1.257E+03 COMPRESSIVE CAPACITY = 3.13.000E+00 SLENDERNESS RATIO OF WEB (H/W) = 5.000E+00 Z AXIS = 0.PRO CODE CHECKING (SOUTHAFRICAN STEEL/SAB-0162-01(1993)) ************************************** ALL UNITS ARE . South African Codes .37E+02 MATERIAL PROPERTIES (UNIT = MPA) -------------------------------FYLD = 300.53E+02 PY = 2.Steel Design Per SAB Standard SAB0162-1:1993 1 UNI GY -70 PERFORM ANALYSIS PARAMETER CODE SABS0162 FU 450000 ALL BEAM 1 ALL FYLD 300000 ALL TRACK 2 ALL CHECK CODE ALL FINISH 17B.000 KL/RY = 194.738E+02 TENSILE CAPACITY = 2.263 KL/RZ = 43.00 OMEGA-1 (Z-AXIS) = 1.00 -560.45E+03 SY = 1.996E+03 CTORFLX = 3.55E+01 MEMBER LENGTH = 8.94E+04 SZ = 1.142 ALLOWABLE KL/R = 300.M) --------------------------------CRY = 3.00E+02 IZ = 2.8 4.00 MEMBER PROPERTIES (UNIT = CM) ----------------------------CROSS SECTION AREA = 8.0 FU = 345.00 4.04E+01 772 — STAAD.KNS MEMBER TABLE MET (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= * 1 ST 457X67UB (SOUTHAFRICAN SECTIONS) FAIL SAB-13.17B.399E+01 MRZ = 1.5 Output ************************************** STAAD.730E+02 MISCELLANEOUS INFORMATION -------------------------NET SECTION FACTOR FOR TENSION = 1.00 SHEAR FORCE (KNS) : Y AXIS = 0.738E+02 FACTORED MOMENT RESISTANCE : MRY = 6.355E+02 FACTORED SHEAR RESISTANCE : VRY = 6.0 SECTION CAPACITIES (UNIT .Pro .00 0.000 OMEGA-1 (Y-AXIS) = 1.871E+02 VRZ = 5.30E+03 PZ = 1.134 1 0. Section 18 Spanish Codes International Design Codes Manual — 773 . Pro .774 — STAAD. Design of members per NBE-MV103-1972 requires the STAAD Eurozone Design Codes SELECT Code Pack.Pro is capable of performing steel design based on the Spanish code NBE-MV103-1972 Cálculo de estructuras de acero laminado en edificación (Calculation of rolled steel structures construction). its value stays at that specified number until it is specified again. Default values of commonly used parameters for conventional design practice have been chosen as the basis. Note: Once a parameter is specified.2 of the Technical Reference Manual.18A. Spanish Codes . Calculate moment at 1/10th points along the beam and maximum Mz for design 2. International Design Codes Manual — 775 .1-Spanish Steel Design per NBE-MV103-1972 Parameters Parameter Name CODE Default Value Description - Must be specified as SPANISH. 1. Table 18A.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to the BSK 99 code. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. 18A. Check sections with end forces only or at locations specified by a SECTION command. BEAM 0 Parameter to control the number of sections to checked along the length of a beam: 0.0 check. Table 26A.1 contains a complete list of available parameters with their default values. See section 5. Check sections with end forces and forces at location of BEAM 1.52. This is the way STAAD works for all codes. Design Code to follow.Steel Design per NBEMV103-1972 STAAD. 4. Slenderness ratio = (KY)·(LY)/(r ) y LY Member Length 776 — STAAD. Consider the section failed and cease code checks if the section fails the check per this clause DMAX DMIN 0 ETA 1 FYLD KY KZ LVV 255 MPa 1.5.3 1.5.1.5. Continue with other code checks. K factor in local y axis. denoting end point for calculation of "Deflection Length".5.1 and 3. Controls the check Mcrrs as per Section 5. Do not perform this check.3. Minimum allowable depth of steel section.1. Compression length in local y axis.0 Member Length Yield strength of steel. DJ1 Start node of member DJ2 End node of member Node no. even if the section fails the check per this clause 2.0 1. β value as specified in Sections 0 3.18A. K factor in local z axis.Pro .1.9. Perform this check 1.4.1 and 3.5. 5. Member length to be used in Cl.5.4 meter Maximum allowable depth of steel section.9.5. denoting starting point for calculation of "Deflection Length" .Steel Design per NBE-MV103-1972 Parameter Name C1 Default Value Description 0 β value as specified in Sections 3. 25. Critical Cl. 3. 0.1. Spanish Codes . C2 0 CB 1 DFF None "Deflection Length" / Maximum allowable local deflection Node no. Secondary steel (250) NSF 1. Slenderness ratio = (KZ)·(LZ)/(r ) z MAIN 1 Sets the slenderness limit for checks per Section 3.5.1 contains a list of available parameters and their default values. Spanish Codes . Main steel (200) 2. 1.2 Design Parameters These parameters not only act as a method to input required data for code calculations but give the engineer control over the actual design process. = Maximum level of detail RATIO 1 TB 1 TRACK 0 UNF 1 Unsupported length as a fraction of the actual member length.0 Net tension factor for tension capacity calculation. Net section factor for tension members. = Intermediate level of detail 2. as applied to Wn per Cl. = Minimum level of detail 1. 18A. 0. 4.Concrete Design per EHE STAAD.6. Unsupported length for allowable bending stress. Design of members per EHE requires the STAAD Eurozone Design Codes SELECT Code Pack.Parameter Name LZ Default Value Description Member Length Compression length in local z axis. Default values. International Design Codes Manual — 777 .5.Pro is capable of performing concrete design based on the Spanish code EHE Española del Hormigón Estructural (Spanish Structural Concrete). which are commonly used numbers in conventional design practice. Permissible ratio of loading to capacity. have been used for simplicity. UNL Member Length 18A. Table 25A. Used to control the level of detail in the output. Depth of the concrete member.5 in DEPTH YD EFACE 0. Clear cover to reinforcing bar at top of cross section. Maximum main reinforcement bar size. Yield Stress for main reinforcing steel.18A. Distance of face of support from end node of beam. Clear cover to reinforcing bar along the side of the cross section.Concrete Design per EHE Note: Once a parameter is specified.5 in Description Clear cover to reinforcing bar at bottom of cross section.5 in CLT 1.0 ksi 60 ksi 60 ksi Number 55 bar Specified compressive strength of concrete. This is the way STAAD works for all codes. Used for shear and torsion calculation. Table 18A. its value stays at that specified number until it is specified again.0 Minimum main reinforcement bar size Minimum secondary (stirrup) reinforcement bar size. A factor by which the column design moments will be magnified. MMAG NSE CTION 12 778 — STAAD. This value defaults to YD as provided under MEMBER PROPERTIES.Pro . Spanish Codes . Yield Stress for secondary reinforcing steel. FC FYMAIN FYSEC MAX MAIN 4. Number of equally-spaced sections to be considered in finding critical moments for beam design. MINMAIN Number 10 bar MINSEC Number 10 bar 1. CLS 1.2-Spanish Concrete Design per EHE Parameters Parameter Name CLB Default Value 1.0 Face of Support Note: Both SFACE & EFACE must be positive numbers. Note: Both SFACE & EFACE must be positive numbers. SFACE 0. Column Design: TRACK 0 output plus intermediate level of detail. Spiral Column. Used for shear and torsion calculation.0 Description Used to specify type of column shear reinforcement: 0. 1. Tied Column. International Design Codes Manual — 779 . Beam Design: Intermediate level of detail.Parameter Name REINF Default Value 0.0 Distance of face of support from start node of beam.0 Used to specify detail of output: 0. Beam Design: TRACK 1 detail plus steel required at 1/12th secitons. This value defaults to ZD as provided under MEMBER PROPERTIES. Only minimum details are printed for beam or column designs. Column Design: detailed output. WIDTH ZD Width of the concrete member. 1. TRACK 0. 2. 780 — STAAD.Pro . Section 19 Swedish Codes International Design Codes Manual — 781 . 782 — STAAD.Pro . Swedish Codes . its value stays at that specified number until it is specified again. Eurozone Design Codes SELECT Code Pack. CB. β . See section 5. Note: Once a parameter is specified. Table 19A. Buckling length coefficient. Design Code to follow. for the critical lateral buckling moment according to the theory of elasticity.52. The reduction factor. BY 1 BZ 1 CB 1 CMY 1 International Design Codes Manual — 783 . BEAM 1 (Required) Directs the program to divide the beam element into 13 equal length sections for section checks.2 of the Technical Reference Manual.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to the BSK 99 code. β for buckling cd about the strong axis (typically z-z axis).19A. Default values of commonly used parameters for conventional design practice have been chosen as the basis. This is the way STAAD works for all codes. Buckling length coefficient.1-Swedish Steel Design per BSK 99 Parameters Parameter Name CODE Default Value Description Must be specified as BSK99. for buckling cd about the weak axis (typically y-y axis). These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process.Pro is capable of performing steel design based on the Swedish code BSK 99 Swedish Regulations for Steel Structures.Steel Design per BSK 99 STAAD. 19A. Table 19A.1 contains a complete list of available parameters with their default values. Describes the boundary conditions for lateral buckling. Design of members per BSK 99 requires the STAAD N. Material factor and security class factor.Steel Design per BSK 99 Parameter Name CMZ Default Value 1 Description Depends on loading and boundary conditions for bending and controls Mlcr and corresponding moments. β . Buckling curve coefficient. Calculates the design moment about the zaxis. Yield strength of steel. Buckling curve coefficient.15 1 0 Permissible ratio of loading to capacity.Pro . Swedish Codes . β . Minimum allowable depth of steel section. γ ·γ .19A. about local z1 axis. SSZ 0 784 — STAAD. m n CY 0 CZ 0 DMAX DMIN FYLD MF RATIO SSY 1 meter 0 235 MPa 1. Maximum allowable depth of steel section. Calculates the design moment about the yaxis. about local y1 axis. = Max. = Joint capacity. = Max. International Design Codes Manual — 785 . = Joint capacity. = Suppress critical member stresses (2 lines/member) 1.. 0. = Print von Mises stresses 3. output for end no.Parameter Name TRACK Default Value 0 Description Used to control the level of detail in the output. 1 32. design values) (6 lines/beam) 2. = Member results. sorted by member number (2 lines/member) 9. 2 49. = Print all critical member stress (i. 98. 99./min. = Joint force output. UNL Member Length Unrestraint length of member used in calculating the lateral-torsional resistance moment of the member./min.e. = Print detailed report for each member 31. output for end no. 786 — STAAD.Pro . Concrete Design per BBK 94 STAAD. Swedish Codes .Pro is capable of performing concrete design based on the Swedish code BBK 94 Swedish Handbook for Concrete Structures. Design of members per BBK 94 requires the STAAD N.19B. Eurozone Design Codes SELECT Code Pack. International Design Codes Manual — 787 . Pro .788 — STAAD. in years. CLEAR 25 mm Clearance of reinforcement measured from concrete surface to closest bar perimeter.0 Actual age of concrete.19C.0 Face of support location at end of beam. These parameters not only act as a method to input required data for code calculations but give the Engineer control over the actual design process. Table 19B. Beam or column braced in both directions 1. in current units. This is the way STAAD works for all codes. 2. its value stays at that specified number until it is specified again. International Design Codes Manual — 789 . Default values of commonly used parameters for conventional design practice have been chosen as the basis. One-way plate or column braced in only the local Z direction. 3. Bracing parameter for design: 0.1-Swedish Concrete Design per BBK 94 Parameters Parameter Name CODE Default Value Description Must be specified as SWEDISH. Note: Both SFACE & EFACE must be positive numbers.1 contains a complete list of available parameters with their default values.52. Design Code to follow. ACTAGE BRACE 70 0. Drying exposure. Note: Once a parameter is specified. in percent. Table 19C. Column braced in only the local Y direction. Column unbraced in either direction. in current units.1 Design Parameters The program contains a number of parameters which are needed to perform and control the design to the BBK 94 code. See section 5.2 of the Technical Reference Manual. DRYCIR 100 EFACE 0. Two faced distribution about major axis. 2.Parameter Name ELY Default Value 1. in degrees. NA — Aggressive 3. Member length factor about local Z direction for column design. Minimum size permitted for main reinforcement bar. 4. 3. Faced symmetric distribution 10 MOY MOZ NMAG REIANG RELHUM RFACE 790 — STAAD. in percent. 7 days 32 Age when loaded.0 Description Member length factor about local Y direction for column design. Column bar arrangement 1. MA — Very aggressive ELZ 1.Pro . Relative humidity. Environment class 1. in days. Four longitudinal bars. 500 N/mm 2 Yield strength of main reinforcing steel. LA — Least aggressive 2. moy factor moz factor nmag factor 0 40 1 Reinforcement angle. Two faced distribution about minor axis. Maximum size permitted for main reinforcement bar.0 ENVIR 2 FC FYMAIN LAGE MAX MAIN MINMAIN 35 N/mm 2 Compressive strength of concrete. Stirrup diameter Torsion angle. Track parameter to control output detail 10. Note: Both SFACE & EFACE must be positive numbers. in degrees. in degrees. Slab — Plane stress design. STIRANG STIRDIA TORANG TRACK 90 10 mm 45 10 Stirrup angle. Beam — Ultimate limit state design only 20. 12. Beam — Ultimate limit state and Service limit state design with tension stiffening. Beam — Ultimate limit state and Service limit state design & Slab — Two-way plate design 11.Parameter Name SFACE Default Value 0 Description Distance from the start node of the beam to face of support for shear design. 30. International Design Codes Manual — 791 . Slab — Simplified membrane design. 792 — STAAD.Pro . Described below is the command specification for various sections: 20A.00X8. The section names are mentioned in Tables 5 through 28 of that manual.625 18 TA ST 1.2 International Design Codes Manual — 793 .1 Member Properties In order to do this design in STAAD.8 9 TA ST I8.Section 20 American Aluminum Code STAAD.00X13.50PIPEX160 15 TA ST T(A-N)6.Pro is capable of performing aluminum member design based on the ASD 1994 Specifications for Aluminum Structures.00X11.1 Standard single section MEMB-LIST TA ST SECTION-NAME Example 1 TO 5 TA ST CS12X11. 20A. All of those tables except Table 10 (Wing Channels) and Table 20 (Bulb Angles) are available in STAAD.1 11 33 45 67 TA ST LS8.00X8. Sixth Edition (October.1. the members in the structure must have their properties specified from Section VI of the above-mentioned manual. Design of members per ASD 1994 requires the STAAD US Specialized Design Codes SELECT Code Pack.00X0. 1994). 2 and 4. 4.500WALL 20A.75 SP 1.75 20A.1 SP 0.2.2 Double channel back-to-back MEMB-LIST TA BACK SECTION-NAME SPACING VALUE Example 3 TA BACK C(A-N)7X3.2 Double channel front-to-front MEMB-LIST TA FRONT SECTION-NAME SPACING VALUE Example 2 TA FRONT CS12X10.21 on pages I-A-27 through I-A-40.3 Design Procedure The design is done according to the rules specified in Sections 4.1 through 3.00X0.33 SP 0.1 Double angle long leg back-to-back MEMB-LIST TA LD SECTION-NAME SPACING VALUE Example 14 TA LD LS4.0 20A. The adequacy of the member is checked by calculating the value of the left- 794 — STAAD.5X3X0.2 Double angle short leg back-to-back MEMB-LIST TA SD SECTION-NAME SPACING VALUE Example 12 TA SD L3.5 20A. The allowable stresses for the various sections are computed according to the equations shown in Section 3.Section 20 American Aluminum Code 23 25 29 TA ST 20X12RECTX.00X3.4.2.4 on pages I-A-41 and I-A-42 of the Aluminum code.5 SP 0.Pro .3 SP 1.1.5 5 TA BACK C15X17.0 4 TA FR CS10X10.375 SP 1.61 SPACING 1.1.5 20A.4.25 13 TA SD L8X6X0. Table 20A.0. the member is declared as having PASSed.3-1 in Section I-B of the Aluminum specifications provides information on the properties of the various alloys. its value stays at that specified number until it is specified again. 4. If the highest RATIO among these equations turns out to be less than or equal to 1.2-1. See section 5. This left-hand side value is termed as RATIO. 4.2 below for a list of values for this parameter and the alloy they represent.1.1.4 Design Parameters The following are the parameters for specifying the values for variables associated with the design. The default value represents the alloy 6061-T6.1-3. 1 - Material used in the section is an Alclad. See Table 14A.3 for open sections is currently not implemented in STAAD. If it exceeds 1. This is the way STAAD works for all codes. the member has FAILed the design requirements. ALLOY 34 This variable can take on a value from 1 through 40.Pro.Section 20 American Aluminum Code hand side of equations 4.1 of the Technical Reference Manual.1.1-2.4-2. Note: The check for torsion per Clause 4.4-1 and 4. 4.1.0.48. Table 3. 0 - Material used in the section is not an Alclad. ALCLAD 0 Defines if material is Alclad. International Design Codes Manual — 795 . 4. Note: Once a parameter is specified. 20A.1-1.1-Aluminum Design Parameters Parameter Name CODE Default Value Description - Must be specified as ALUMINUM Design Code to follow. 0.01 (for a column completely prevented from torsional buckling) to any user specified large value. This value must be provided in the current units.7. If the BEAM value is 0. Values can range from 0. See Equation 3.Pro . It is a fraction and is unitless. It is used to compute the KL/R ratio for twisting for determining the allowable stress in axial compression. and instead. the adequacy of the member is determined by checking a total of 13 equally spaced locations along the length of the member. Effective length factor for torsional buckling. If neither the BEAM parameter nor any SECTION command is specified.0. DMIN 0. STAAD will terminate the run and ask the user to provide one of those 2 commands.4. the 13 location check is not conducted. Maximum depth permissible for the section during member selection.0 If this parameter is set to 1. This value must be provided in the current units. DMAX 1000 in. checking is done only at the locations specified by the SECTION command (See STAAD manual for details).Section 20 American Aluminum Code Parameter Name BEAM Default Value Description 0.0 796 — STAAD.2-6 on page I-A-28 of the Aluminum specifications for details. This rule is not enforced for TRUSS members.0 in KT 1. Minimum depth required for the section during member selection. Effective length for overall column buckling in the local Y-axis.4. It is used to compute the KL/R ratio for twisting for determining the allowable stress in axial compression.01 (for a column completely prevented from torsional buckling) to any user specified large value.01 (for a column completely prevented from buckling) to any user specified large value.0 LT Member length LY Member length International Design Codes Manual — 797 . KZ 1.01 (for a column completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the allowable stress in axial compression.2-6 on page I-A-28 of the Aluminum specifications for details.0 Effective length factor for overall column buckling in the local Y-axis. It is a fraction and is unit-less. Values can range from 0.01 (for a column completely prevented from buckling) to any user specified large value. Unbraced length for twisting. It is a fraction and is unit-less. It is input in the current units of length. Values can range from 0. It is used to compute the KL/R ratio for determining the allowable stress in axial compression. It is used to compute the KL/R ratio for determining the allowable stress in axial compression. Effective length factor for overall column buckling in the local Z-axis. Values can range from 0. See Equation 3. It is input in the current units of length.Section 20 American Aluminum Code Parameter Name KY Default Value Description 1.7. Values can range from 0. Sidesway is present along the local Y-axis of the member 1 - There is no sidesway along the local Y-axis of the member. The values are: 0 .01 (for a column completely prevented from buckling) to any user specified large value.0 Factor that indicates whether or not the structure is subjected to sidesway along the local Y axis of the member. This variable can take on a value from 1 through 4. page I-A-41 of the Aluminum specifications.1. It is used to compute the KL/R ratio for determining the allowable stress in axial compression.1.3-1 in Section I-B of the Aluminum specifications. 798 — STAAD. PRODUCT 1 SSY 0. They represent: 1 - All 2 - Extrusions 3 - Drawn Tube 4 - Pipe The default value stands for All. It is input in the current units of length. The PRODUCT parameter finds mention in Table 3.Section 20 American Aluminum Code Parameter Name LZ Default Value Description Member length Effective length for overall column buckling in the local Z-axis.Pro . Values can range from 0. The sidesway condition is used to determine the value of Cm explained in Section 4. ny and na are dependent upon whether the structure being designed is a building or a bridge. In Table 3.4.1. Users may convey this information to STAAD using the parameter STRUCTURE. The values that can be assigned to this parameter are: 1 - Buildings and similar type structures 2 - Bridges and similar type structures STR UCTURE 1 International Design Codes Manual — 799 . The values are: 0 - Sidesway is present along the local Z-axis of the member 1 - There is no sidesway along the local Z-axis of the member. The sidesway condition is used to determine the value of Cm explained in Section 4.4-1 in Section I-A of the Aluminum specifications. page I-A-41 of the Aluminum specifications. it is mentioned that the value of coefficients nu. STIFF Member length Spacing in the longitudinal direction of shear stiffeners for stiffened flat webs.0 Factor that indicates whether or not the structure is subjected to sidesway along the local Z axis of the member.1. It is input in the current units of length.21 on page I-A-40 of the Aluminum specifications for information regarding this parameter. See section 3.Section 20 American Aluminum Code Parameter Name SSZ Default Value Description 0. UNL Member length Distance between points where the compression flange is braced against buckling or twisting. and PASS/FAIL status.0 inch of a weld. ratio. The allowable values are: 1 - Prints only the member number. it is mentioned that the value of coefficients Kt and Kc are dependent upon whether or not. 4 - Prints the values of variables used in design in addition to that printed by TRACK 3. In Table 3.Pro .4-2 in Section I-A of the Aluminum specifications.Section 20 American Aluminum Code Parameter Name TRACK Default Value Description 2 This parameter is used to control the level of detail in which the design output is reported in the output file. section name. This value is used to compute the allowable stress in bending compression.Region is farther than 1. the location of the section where design is done is within 1.Region is within 1. The values that can be assigned to this parameter are: 0 . 2 - Prints the design summary in addition to that printed by TRACK 1 3 - Prints the member properties and alloy properties in addition to that printed byTRACK 2. The WELD parameter is used in STAAD for this purpose. This value must be provided in the current units.0in from a weld 1 .0in from a weld WELD 0 800 — STAAD. 4.2-Alloy Parameters Value 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 1100-H12 1100-H14 2014-T6 2014-T6510 2014-T6511 2014-T651 3003-H12 3003-H14 3003-H16 3003-H18 3004-H32 3004-H34 3004-H36 3004-H38 5005-H12 5005-H14 5005-H32 5005-H34 5050-H32 5050-H34 5052-H32 5052-H34 5083-H111 5086-H111 5086-H116 Name International Design Codes Manual — 801 .1 Aluminum Alloys available in STAAD Table 20A.Section 20 American Aluminum Code 20A. Section 20 American Aluminum Code Value 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 5086-H32 5086-H34 5454-H111 5454-H112 5456-H111 5456-H112 6005-T5 6105-T5 6061-T6 6061-T6510 6061-T6511 6061-T651 6063-T5 6063-T6 6351-T5 Name 20A.Pro .5 of the Technical Reference Manual for general information on Code Checking.5 Code Checking The purpose of code checking is to determine whether the initially specified member properties are adequate to carry the forces transmitted to the member due to the loads on the structure. Refer to Section 5. Code checking is done at the locations specified by either the SECTION command or the BEAM parameter described above. Example Problem 1 in the Getting Started and Tutorials Manual for STAAD provides an example on the usage of the CHECK CODE command. 20A.5.48. Refer to Section 2.1 Example Sample input data for Aluminum Design PARAMETER CODE ALUMINUM 802 — STAAD.2 of the Technical Reference Manual for details the specification of the Code Checking command. 6 Member Selection The member selection process involves the determination of the least weight member that PASSes the code checking procedure based on the forces and moments of the most recent analysis. a member specified initially as a channel will have a channel selected for it.6 of the Technical Reference Manual for general information on Member Selection. Example Problem 1 in the Getting Started and Tutorials Manual for STAAD provides an example on the usage of the SELECT MEMBER command.3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 2. Refer to Section 5. For example. The section selected will be of the same type as that specified initially.48. International Design Codes Manual — 803 .2 MEMB 3 4 ALLOY 35 ALL PRODUCT 2 ALL TRACK 3 ALL SELECT ALL ALCLAD 1 ALL STRUCT 1 ALL CHECK CODE ALL 20A.Section 20 American Aluminum Code BEAM 1 ALL KY 1. Pro .804 — STAAD. Section 21 American Transmission Tower Code International Design Codes Manual — 805 . Pro .806 — STAAD. The NSF parameter (see the Parameters table shown later in this section) may be used if the International Design Codes Manual — 807 . 21A. Single Angles. buckling. Channels. etc.1 Design Axial Tensile Stress Design tensile stresses are calculated on the basis of the procedure described in section 3.Pro.1 General Comments The ASCE 10-97 code is meant to supercede the older edition of the code. such as provisioning of stiffeners and checking the local effects like flange buckling. Tees. Design of members per ASCE 10-97 requires the STAAD US Std Design Codes SELECT Code Pack. 21A. Design of HSS sections (those listed in the 3rd edition AISC LRFD manual) and Composite beams (I shapes with concrete slab on top) is not supported. use the commands PARAMETER CODE ASCE 52 To access the ASCE 10-97 code. 21A. fracture and other limiting conditions specified in the standard. S. Tubes and Pipes. in the interests of backward compatibility. web crippling. HP.2 Allowable Stresses per ASCE 10-97 Member selection and code checking operations in the STAAD implementation of ASCE 10-97 are done to resist loads at stresses approaching yielding. The appropriate sections of the ASCE standard where the procedure for calculating the design stresses is explained are as follows. However. To access the ASCE 52 code. use the commands PARAMETER CODE ASCE The detailing requirements. must be performed manually. Design is available for all standard sections listed in the AISC ASD 9th edition manual. It is assumed that you are familiar with the basic concepts of Steel Design facilities available in STAAD. M. Wide Flanges. Please refer to Section 2 of the STAAD Technical Reference Manual for detailed information on this topic. American Transmission Tower Code Steel Design per ASCE 10-97 STAAD.Pro is capable of performing steel design based on the American Transmission Tower code ASCE 10-97 Design of Latticed Steel Transmission Structures. both codes are currently accessible in STAAD. Double Angles. available under the name ASCE Publication 52.2. namely.21A.10. Those stresses are referred to in the standard as Design Stresses. KY.6 through 3.14. 808 — STAAD. The default parameter values have been selected such that they are frequently used numbers for conventional design.3 Design Bending Compressive Stress Calculations for design bending compressive stress about the major axis and minor axis are based on the procedures of section 3.15 for Shear.2.2 Design Axial Compressive Stress Design compressive stress calculation is based on the procedures of section 3.2 for Maximum w/t ratios and Clause 3. 21A.14. LZ and/or KT. Procedures outlined in sections 3.14. American Transmission Tower Code . Capacity of the section is computed for column buckling and wherever applicable. Note: Once a parameter is specified.6 have been implemented. These parameters may be used to control the design process to suit specific modeling needs.2.4 for slenderness limits. 21A.Steel Design per ASCE 10-97 section area needs to be reduced to account for bolt holes.13 for Axial Tension and Bending. The user may control the effective lengths for buckling using the LT.8 have been implemented.Pro . 21A.21A. the procedures of sections 3.4 Design Parameters Design parameters are summarized in the table shown later in this section. Clause 3.1 through 3.2.2 is followed for angles and the procedure of section 3. 21A.12 for Axial Compression and Bending. For angle members under compression.4 Design Bending Tensile Stress Calculations for design bending tensile stress about the major and minor axis are based on the procedures of section 3. KZ parameters (see the Parameters table shown later in this section).9.15.15. Clause 3.14. 21A.9.7 and 3.2. This is the way STAAD works for all codes.15 of the ASCE 10-97.2. its value stays at that specified number until it is specified again.1 is followed for all other sections. 21A. The procedure of section 3. LY.3 Critical Conditions used as criteria to determine Pass/Fail status These are Clause 3. Clause 3. torsional buckling.5 Design Shear Stress Calculation of the design shear stress is based on the procedure outlined in section 3. EQN.0 0 = Perform design at beam ends and section locations specified according to the SECTION command 1 = Perform design at the ends and eleven intermediate sections of the beam CMY CMZ 0. Minimum allowable depth for member selection Indicates what type of end conditions are to be used from among Equations 3. Design Code to follow.7-4.48.3.7-7.3.Table 21A.7-4 thru 3. See section 5. Page 4 (VALID FOR LEG MEMBERS ONLY) 2. DMIN 0. EQN.0 in. EQN. BEAM 1.7-6.75 in. Page 4 4.0 in.85 for sidesway and calculated for no sidesway 45.7-5. Page 5 DBL 0.3.3.1-Steel Design Parameters for ASCE 10-97 Parameter Name CODE Default Value Description - Must be specified as ASCE to design per ASCE 10-97. 1.1 of the Technical Reference Manual.7-7 to determine the KL/R ratio. Page 4 3. Cm value in local y and z axes as defined in equation 3. ELA 4 International Design Codes Manual — 809 .10 of ASCE 10-97. DMAX Maximum allowable depth for member selection Diameter of bolt for calculation of number of bolts required and the net section factor.12-1 on p. EQN. 0.7-9. 3. Page 5.3.7-12.2 as 0.3.0FYLD. American Transmission Tower Code . 1.7-12 thru 3. 1.0 KSI 1.14.3.0 LT Member Length Effective length for warping. Page 5. 2. Page 5 3.10.0 Shear strength of bolt.7-10. Page 5.7-13.Steel Design per ASCE 10-97 Parameter Name ELB Default Value Description 1 Indicates what type of end conditions are to be used from among Equations.714. Page 5 2.7-14 to determine the KL/R ratio. indicates that the angle is connected only by the shorter leg and allowable tensile stress is computed per clause 3. indicates that the angle is connected by both legs and allowable stress in axial tension is 1.Pro .4.3. EQN. Yield Strength of steel Effective length coefficient for warping restraint (clause 3.0 KZ 1. EQN. pg 11) Effective length factor (K) for compression buckling about the Y-axis (minor axis) Effective length factor (K) for compression buckling about the Z-axis (major axis) This parameter is meant for plain angles. KY 1.7-10 and 3.9FYLD.Page 5 FVB FYB FYLD KT 30 KSI 36 KSI 36. Yield strength of bolt. 810 — STAAD.21A. EQN.7-8. EQN.3.0 LEG 0. EQN. indicates that the angle is connected by the longer leg. EQN.3.7-8 thru 3. 4. Compression member. Hanger member.Parameter Name LY Default Value Description Member Length Member Length 2 Length to calculate slenderness ratio for buckling about the Y-axis (minor axis) Length to calculate slenderness ratio for buckling about the Z-axis (major axis) Parameter that indicates the member type for the purpose of calculating the KL/R ratio (SEE CLAUSE 3. Redundant member. Will be used only if flexural compression is on the bottom flange.0 = Sidesway in local y-axis 1. PAGE 3. Tension member.0 = Suppresses printing of allowable stresses 1. Leg member.0 SSZ TRACK 0. Do not perform the KL/R Check LZ MAIN NHL 0 Number of bolt holes on the cross section that should be used to determine the net section factor for tension capacity. KL/R <= 200 3. KL/R <= 150 2.0 Same as above except in local z-axis 0.0 0. KL/R <= 250 10. ASCE 10-97) 1.0 = Prints all allowable stresses UNB Member Length Unsupported length of the bottom flange for calculating flexural strength.0 1.0 SSY 0. KL/R <= 375 (Clause 4C. KL/R <= 500 4. Net section factor for tension members Permissible ratio that determines the cut off point for pass/fail status. 0.4. page 43) 5.0 = No sidesway NSF RATIO 1. A value below this quantity indicates PASS while a value greater than this quantity indicates FAILURE. International Design Codes Manual — 811 . but provided as a fraction of the member length Unsupported length of member for calculation of allowable bending stress UNL Member Length UNT Member Length Unsupported length of the top flange for calculating flexural strength.21A. In general. Note: All values must be provided in the current unit system. Will be used only if flexural compression is on the top flange. Refer to Section 5.2 of the Technical Reference Manual for details the specification of the Code Checking command. Refer to Section 2.48. Refer to Section 5. it may be noted that the concepts followed in MEMBER SELECTION and CODE CHECKING procedures are similar to that of the AISC based design.Pro .3 of the Technical Reference Manual for details the specification of the Member Selection command.6 of the Technical Reference Manual for general information on Member Selection. 812 — STAAD. Refer to Section 2.5 of the Technical Reference Manual for general information on Code Checking. American Transmission Tower Code .0 Same as UNL.48.5 Code Checking and Member Selection Both code checking and member selection options are available in the ASCE 10-97 implementation. 21A.Steel Design per ASCE 10-97 Parameter Name UNF Default Value Description 1. 21B.7 and 4.4 Allowable Axial Compressive Stress Allowable compressive stress calculation is based on the procedures of section 4. Members are proportioned to resist the design loads without exceeding the allowable stresses and the most economical section is selected based on the least weight criteria.Pro is capable of performing steel design based on the ASCE Manuals and Reports on Engineering Practice No. Appropriate sections of this publication are referenced below.9. 52) The member design and code checking in the STAAD implementation of ASCE (Pub.3 Allowable Axial Tensile Stress Allowable tensile stresses are calculated on the basis of the procedure described in section 4. Please refer to Section 2 of the STAAD Technical Reference Manual for detailed information on this topic. 21B. etc.1). It is assumed that you are familiar with the basic concepts of Steel Design facilities available in STAAD. American Transmission Tower Code Steel Design per ASCE Manuals and Reports STAAD. Second Edition Design of members per ASCE 10-97 requires the STAAD US Std Design Codes SELECT Code Pack. must be performed manually.2 Allowable Stresses per ASCE (Pub.1 General Comments The design philosophy and procedural logistics for member selection and code checking is based upon the principles of allowable stress design. and the width-thickness requirements. LY. The following sections describe the salient features regarding the process of calculation of the relevant allowable stresses and the stability criteria being used. the minimum metal thickness requirements. 52 – Guide for Design of Steel Transmission Towers. such as provisioning of stiffeners and checking the local effects like flange buckling.8 have been implemented.21B. KZ parameters (Table 1.6 through 4. The NSF parameter (Table 1. The code checking part of the program also checks the slenderness requirements.1) may be used if the net section area needs to be used. Capacity of the section is computed for column buckling and wherever applicable. web crippling. For angle members under compression. the procedures of sections 4. KY. Two major failure modes are recognized: failure by overstressing and failure by stability considerations.10. torsional buckling. 21B. International Design Codes Manual — 813 . The detailing requirements. 21B. 52) is based upon the allowable stress design method. LZ and/or KX. The user may control the effective lengths for buckling using the LX. Clause 4.1 through 4. The procedure of section 4.2 for Maximum w/t ratios and Clause 4. 21B. See section 5.Steel Design per ASCE Manuals and Reports 21B.75 in.12-1 for Axial Compression and Bending. BEAM 0. Table 21B. The default parameter values have been selected such that they are frequently used numbers for conventional design. DBL 0.2.14.9 Design Parameters These parameters may be used to control the design process to suit specific modeling needs.0 = use the section locations specified according to the SECTION command 3. 21B. American Transmission Tower Code .1 is followed for all other sections. Procedures outlined in sections 4.52.0 2.14. 52) Based Design Parameter Name Default Value Description Must be specified as ASCE 52.15.15 of the ASCE Pub. CODE Design Code to follow.14.1-Steel Design Parameters for ASCE (Pub.0 = at the ends and eleven intermediate sections of the beam Diameter of bolt for calculation of number of bolts required and the net section factor. Specifies locations along member length at which member design is deisgned.15.6 Allowable Bending Tensile Stress Calculations for allowable bending tensile stress about the major and minor axis are based on the procedures of Section 4.2 is followed for angles and the procedure of section 4. Equation 4. 21B.9.14.15 for Shear.5 Allowable Bending Compressive Stress Calculations for allowable bending compressive stress about the major axis and minor axis are based on the procedures of section 4.8 Critical Conditions used as criteria to determine Pass/Fail status These are Clause 4. 52.7 Allowable Shear Stress Calculation of the allowable shear stress is based on the procedure outlined in section 4.13-1 for Axial Tension and Bending. 814 — STAAD.2 of the Technical Reference Manual.21B.4 for slenderness limits.6 have been implemented. 21B.Pro . Equation 4. Page 27 Indicates what type of end conditions are to be used from among Equations.0 Shear strength of bolt.4.7-5.0 in.7-10.9·FYLD 5.4. Page 27 3 = EQN.7-7.4.0·FYLD 4. Page 28 3 = EQN.0 KZ 1.0 LT Member Length International Design Codes Manual — 815 . Page 27.Parameter Name DMAX DMIN Default Value 45.0 in.0 = the angle is connected only by the shorter leg and allowable tensile stress is computed per Cl. 4.4. EQN.0 KSI 1. 4.7-6.7-12. EQN.7-4 thru 4. Description Maximum allowable depth for member selection Minimum allowable depth for member selection Indicates what type of end conditions are to be used from among Equations 4. 3.4. 1 = EQN.0 = the angle is connected by both legs and allowable stress in axial tension is 1.7-13.4.7-8 thru 4. Page 26 (Valid for leg members only) 2 = EQN.4.0 LEG 0.14. Page 28 2 = EQN.4.2 as 0. Yield Strength of steel Effective length coefficient for warping restraint (clause 4. KY 1. pg 36) Effective length factor (K) for compression buckling about the Y-axis (minor axis) Effective length factor (K) for compression buckling about the Z-axis (major axis) This parameter is meant for plain angles. Page 27.7-8.7-10 to determine the KL/R ratio.10.4.4.0 = the angle is connected by the longer leg Effective length for warping.7-14.Page28 ELB 1 FVB FYB FYLD KT 30 KSI 36 KSI 36.7-4. 0. Page 27.7-7 to determine the KL/R ratio. ELA 4 1 = EQN.4. EQN.7-9. Yield strength of bolt. Page 27 4 = EQN. but provided as a fraction of the member length Unsupported length of member for calculation of allowable bending stress UNF 1. 4.0 Member Length UNL 21B.0 0. p. 52 implementation. American Transmission Tower Code . A value below this quantity indicates PASS while a value greater than this quantity indicates FAILURE. 25) 1 = Leg member (KL/r ≤ 150) 2 = Compression member (KL/r ≤ 200) 3 = Tension member (KL/r ≤ 500) 4 = Hanger member per Cl.21B.4.Pro . In general. Level of detail in output LZ MAIN 2 NHL 0 NSF 1.4. it may be noted that the concepts followed in MEMBER SELECTION and CODE CHECKING procedures are similar to that of the AISC based design. Net section factor for tension members Permissible ratio that determines the cut off point for pass/fail status.0 TRACK 0. 816 — STAAD.Steel Design per ASCE Manuals and Reports Parameter Name LY Default Value Member Length Member Length Description Length to calculate slenderness ratio for buckling about the Y-axis (minor axis) Length to calculate slenderness ratio for buckling about the Z-axis (major axis) Parameter that indicates the member type for the purpose of calculating the KL/R ratio (See Cl.0 RATIO 1. 43 (KL/r ≤ 375) 5 = Redundant member (KL/r ≤ 250) 10 = Do not perform the slenderness (KL/r) check Number of bolt holes on the cross section that should be used to determine the net section factor for tension capacity.0 = Prints all allowable stresses Same as UNL. p.0 = Suppresses printing of allowable stresses 1.10 Code Checking and Member Selection Both code checking and member selection options are available in the ASCE Pub. 4C. International Design Codes Manual — 817 .5 of the Technical Reference Manual for general information on Code Checking.48.6 of the Technical Reference Manual for general information on Member Selection.3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 2.48. Refer to Section 5. Refer to Section 5.2 of the Technical Reference Manual for details the specification of the Code Checking command.Refer to Section 2. Pro .818 — STAAD. and analysis. Specify design parameter values.PUN) International Design Codes Manual — 819 . 22A. l l l These operations may be repeated any number of times depending upon the design requirements. 21st Edition (December 2000). Specify whether to perform code checking or member selection. and Specify design parameters to carry out joint checks. The basic process is as follows: 1. The member design facilities provide the user with the ability to carry out a number of different design operations. if different from the default values. titled Recommended Practice for Planning.Section 22 Steel Design per American Petroleum Institute Code The API Steel Design facility in STAAD is based on the API 2A-WSD standard. Define the STAAD model geometry. 2 & 3 of the code. Run the analysis and API design which creates the Geometry file (file extension .1 Design Operations STAAD contains a broad set of facilities for the design of structural members as individual components of an analyzed structure. The operations to perform a design are: l Specify the members and the load cases to be considered in the design. loading. These facilities may be used selectively in accordance with the requirements of the design problem. Joint checks includes “Errata and Supplements” 1. 2. Design and Constructing Fixed Offshore PlatformsWorking Stress Design. 22A. See "Joint Design" for details.2. Therefore.4-1: fv = V / 0.2 Shear Stress Beam Shear Stress Allowable beam shear stress on the gross section must conform to Clause 3.1 Tension Stress Allowable tension stresses. The 21st edition of API Code. as published in 2007.60·Fy 22A. Check and modify the Geometry file as necessary.1 Limitations The parameter SELECT 1. Re-run the analysis to read the modified Geometry file for the final design results. 4.Pro . For the initial run of an API code check. no time is wasted calculating the allowable bending or shear stresses.5 A 820 — STAAD.2 Truss Members A truss member is capable of carrying only axial force. No hydrostatic checks are performed.2. Allowable tension stress on the net section Ft = 0. as calculated in STAAD. etc.2.4-2 of the API code: Fv = 0.Section 22 Steel Design per American Petroleum Institute Code and give preliminary design results. So in design. 22A.0 should not be used while carrying out punching shear checks. clause (3. if there is any truss member in an analysis (like bracing or strut.2 Allowables per API Code For steel design.2. thus reducing design time considerably. 22A. No classification of the joint is performed using the loading.). all joints will be assumed to be a T/Y joint. 22A.1-1). STAAD compares the actual stresses with the allowable stresses as defined by the American Petroleum Institute (API-RP2A) Code. It can be used in initial runs for member selection.1. it is wise to declare it as a truss member rather than as a regular frame member with both ends pinned.2.4·Fy The maximum applied beam shear stress is per Eqn 3.1. is used as the basis of this design (except for tension stress). are based on the API Code. 3. 2-1 in the API Code when the largest effective slenderness ratio. is: a. It should be noted that during code checking or member selection. Fb = [0.2.2-3) F xc = the inelastic local buckling stress. Fb = [0. 22A.2-4) 22A. as given in Clause 3.3.15.1.500/Fy < D/t ≤ 3.2.1-1/2.1-1 and 3.2-2) of the Code.2.1-2 when fa/Fa > 0.2. When D/t ≤ 1.3.72 . the critical elastic xe buckling coefficient = 0. vt 22A.0. the lesser of F Where: xe or F xc is substituted for F .4-4: Fvt = 0.4-3 of the API code.2.2. xy F = the elastic local buckling stress calculated with C.5 Bending Stress The allowable bending stress for tension and compression for a symmetrical member loaded in the plane of its minor axis.000/Fy < D/t ≤ 300 (Imperial Units).3 Stress Due to Compression The allowable compressive stress on the gross section of axially loaded compression members is calculated based on the formula 3.2.58 Fy D/(Et)]Fy International Design Codes Manual — 821 .3 of the API code. When 3.000/Fy (Imperial Units). When 1. otherwise formula 3. Kl/r is less than or equal to C .500/Fy (Imperial Units).4·Fy F is the maximum torsional shear stress per Clause 3.4 Combined Compression and Bending Members subjected to both axial compression and bending stresses are proportioned to satisfy API formula 3. then the allowable compressive stress is c c increased as per formula (3. the program does not compute the second 3.75Fy b.3. 3. If Kl/r exceeds C . Where: Cc = 2π 2 E Fy For D/t > 60.1-3 applies.0.3 (3.Section 22 Steel Design per American Petroleum Institute Code Torsional Shear Stress Allowable torsional shear stress per Eqn.2. Fb = 0.84 .74 Fy D/(Et)]Fy c.2.3. if fa/Fa > 1. (3.2. 1 of the code. The conditions to be checked for each joint are as given below: 0.1 .Simple joint diagram Definitions θ = Brace included rage g = Gap between braces t = Brace wall thickness at intersection T = Chord wall thickness at intersection d = Brace outside diameter D = Chord outside diameter β = d/D γ = D/(2T) τ = t/T Joint Validity The validity range of the joints that are identified will be checked as per Cl.0 10 ≤ γ ≤ 50 30° ≤ θ ≤ 90° 822 — STAAD.2 ≤ β ≤ 1.Section 22 Steel Design per American Petroleum Institute Code 22A.Pro .6 Simple Joints: Capacity Checks A typical joint and the terms involved with the joint checks are given below: Figure 22A. 4.3.2. 6 (for K joints) If any of these conditions are not satisfied for the joint under consideration.3. You can use the FYLD parameter to reset the yield strength. The program will.6 by default) Q and Q are the strength factor and the Chord factor that are to be u f determined based on the joint type. FSJPc FSJM c 2 Q f = 1 + C1 − C 2 M y − C3A Py FSJPc FSJM c A= + Py M y 2 2 P = axial load c 2 2 M c = M ipb + M opb C .Section 22 Steel Design per American Petroleum Institute Code F = 90 ksi (500 MPa) y g/D > -0.8 International Design Codes Manual — 823 . Table.8 of the tensile stress. 4. y if less) FSJ = the factor of safety parameter (1. Joint Capacity The capacity of the joint. is evaluated as: a Pa = Q uQ f F yc T 2 FSJsinθ The allowable capacity for brace bending moment.3 0.2 0. P .3-1 of the API code). however.3 of the code (ref. perform the joint checks as the code allows for the design of such joints with modified values of yield strength. is to be determined u as given in Section 4. Q .2 0.3 0 0. the programissues a warning message corresponding to the invalid parameter(s). C . both the axial capacity and the moment capacity is The allowable capacity for brace axial load. The strength factor. and C are factors determined by the following table: 1 2 3 Joint Type K joints under brace axial loading T/Y joints under brace axial loading C 1 C 2 C 3 0. is evaluated as: a M a = Q uQ f F yc T d FSJsinθ 2 Where: F = the yield stress of the chord member at the joint (or 0. M . For joints that are a mixture of K.0 opb 22A. some or all of these parameter values may have to be changed to exactly model the physical structure.1.2 0 0 0 0. wile in the real structure it may be 1.3 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.3. are listed in Table 22A.4 0. with their default values. or Y joints. which means no allowable stresses of the member will be printed.9 β = 1.Section 22 Steel Design per American Petroleum Institute Code Joint Type X joints under brace axial loading β ≤ 0. the program performs the following interaction check as given by Cl 4.5.2 0. coefficients are linearly interpolated between listed values.4 All joints under brace moment loading Note: For values of β between 0. by default the KZ value (k value in local z-axis) of a member is set to 1.6 of the code: P Pa M + M + a ipb 2 M Ma ≤ 1. as shown in the input instruction (Section 5).5 0. the KZ value in the program can be changed to 1.0. These parameters communicate design decisions from the engineer to the program. Depending on the particular design requirements for an analysis. Note: Once a parameter is specified. The default parameter values have been selected such that they are frequently used numbers for conventional design. In case the joint is subjected to combined axial load and bending moments (in-plane and/or out-of-plane). its value stays at that specified number until it is specified again.0. Similarly. For example.2 0. the capacity of the joint is evaluated as a weighted average of the capacities of each joint. X.0 C 1 C 2 C 3 0. This is the way STAAD works for all codes.0. the TRACK value of a member is set to 0.9 and 1. These parameter names.5. In that case.Pro . 824 — STAAD. 0 in 0.0 = Cb value to be calculated Any other value will mean the value to be used in design CMY CMZ DMAX DMIN FSJ 0.0 = design only for end moments or those at locations specified by the SECTION command.5 of AISC 0.0 Beam parameter: 0.85 for sidesway and calculated for no sidesway 100.0 = calculate moments at twelfth points along the beam.1-American (API) Steel Design Parameters Parameter Name CODE Default Value Description - Must be specified as API Design Code to follow. CB 1. Yield strength of steel.0. See section 5. FYLD 36 ksi International Design Codes Manual — 825 . 2. 1.6 Cm value in local y & z axes Maximum allowable depth Minimum allowable depth Factor of safety used for joint checks. and use the maximum Mz location for design.0 = Same for BEAM 1. BEAM 1.0 1.48.Section 22 Steel Design per American Petroleum Institute Code Table 22A. but additional check is made at each end.1 of the Technical Reference Manual.0 Cb value as used in Section 1. Length in local Y-axis to calculate slenderness ratio.Section 22 Steel Design per American Petroleum Institute Code Parameter Name KY Default Value Description 1. 0. 1.0 = Main member 2. Typically the minor axis. Permissible ratio of the actual to allowable stresses Design for sidesway. Design for slenderness.0 K value in local y-axis.Pro .0 Net section factor for tension members.0 = Sidesway in local y-axis 1.0 = Secondary member KZ 1. Length in local Z-axis to calculate slenderness ratio.0 = No sidesway RATIO 1. K value in local z-axis.0 NSF 1. Typically the major axis.0 Design for sidesway in local z-axis 826 — STAAD.0 SSZ 0.0 LY Member Length LZ Member Length MAIN 0.0 SSY 0. as explained in section 3. 1.0 = Welding is one side only except for wide flange or tee sections. 0 = Welding is both sides. 0.0 = Suppress all checks except punching shear UNF 1.4 X FLYD Minimum thickness Allowable welding stress Note: The parameters DMAX and DMIN are only used for member selection.1 of the API code.0 Same as above provided as a fraction of actual member length Unsupported length for calculating allowable bending stress Weld type.0 = Print all critical member stresses 2.1. International Design Codes Manual — 827 .0 = 3. For closed sections like pipe or tube.Section 22 Steel Design per American Petroleum Institute Code Parameter Name TRACK Default Value Description 0.0 = Print design output at the minimum level of detail. 1. the welding will be only on one side. UNL Member Length WELD 1 WMIN WSTR 1. 2.0 = 100.0 Controls the level of detail in the output: 0. where the web is always assumed to be welded on both sides.16 in. l Refer to Section 2. the lightest section which fulfills the code requirements for the specified member. Thus for a local joint check.).Pro .5 of the Technical Reference Manual for general information on Code Checking. i. 22A. shear. The section selected will be of the same type section as originally designated for the member being designed. the program uses the start and end forces for code checking.6 Chord Selection and Q Parameter f Q is a factor to account for the presence of nominal longitudinal stress in the chord. 22A.4 Code Checking The purpose of code checking is to ascertain whether the provided section properties of the members are adequate as per API. the program calculates and prints whether the members have passed or failed the checks. tension. Member selection cannot be performed on members whose section properties are input as prismatic. l l Member selection can be performed with all types of hollow steel sections. Selection of members whose properties are originally input from a user created table will be limited to sections in the user table. Refer to Section 5.5 Member Selection The program is capable of performing design operations on specified members. the value of the ratio of the critical condition (overstressed for value more than 1. it is more accurate to use the actual chord moment in the middle of the brace foot print.0 or any other specified RATIO value). Once an analysis has been performed. Refer to Section 5. When f calculating Q for the joints.48.Section 22 Steel Design per American Petroleum Institute Code 22A. the critical condition of API code (like any of the API specifications for compression.6 of the Technical Reference Manual for general information on Member Selection.2 of the Technical Reference Manual for details the specification of the Code Checking command. Code checking can be done with any type of steel section listed in Section 2.3 of the Technical Reference Manual for details the specification of the Member Selection command. If the moment varies significantly along the chord. 828 — STAAD.48. Member selection can also be constrained by the parameters DMAX and DMIN which limits the maximum and minimum depth of the members. the moments used in the chord stress calculation will be from f the computer node results and not the representative moments underneath the brace. the governing load case. the local chord moment (under the brace) should be used. etc. When code checking is selected. the program can select the most economical section. The tests reported in Reference I [1] were performed with a constant moment along the chord.2 of the Technical Reference manual.. and the location (distance from the start of the number of forces in the member) where the critical condition occurs. If no sections are specified. Code checking is done using the forces and moments at specific sections of the members.e. Refer to Section 2. there will be an asterisk (*) mark on front of the member. 22A. OTC 4828. for T joints the first member modeled will be selected as the chord. TJ. in most cases. Normally a value of 1.7 Tabulated Results of Steel Design For code checking or member selection. RATIO prints the ratio of the actual stresses to allowable stresses for the critical condition. CRITICAL COND the section of the AISC code which governs the design. International Design Codes Manual — 829 . PW. In the automatic selection of the chord two collinear members (5 degree tolerance) are used to identify the chord.1 Reference 1 Ref I: Boone. LOADING provides the load case number which governed the design. The chord is then selected from one of the two members based on the larger diameter then thickness or then by the minimum framing angle. Although STAAD does consider all the member forces and moments (except torsion) to perform design. and Hoadley. JA.Section 22 Steel Design per American Petroleum Institute Code STAAD calculates Q based on the moment at the chord member. MY. FX. The items in the output table are explained as follows: Member the member number for which the design is performed. RESULTS prints whether the member has PASSed or FAILed. LOCATION specifies the actual distance from the start of the member to the section where design forces govern.0 or less will mean the member has passed. and MZ provide the axial force. MY and MZ are printed since they are the ones which are of interest. moment in local Y-axis. TABLE AISC steel section name which has been checked against the steel code or has been selected. 1984 22A. Yura. The chord member can be f selected automatically by initial screening by the program (based on geometry and independent of loading) or specified in the External file.6. and the moment in local Z-axis respectively. Ultimate Strength if Tubular Joints – Chord Stress Effects. only FX. If the RESULT is FAIL. the program produces the results in a tabulated fashion. You should confirm that the chord either be assigned by the program or the user is representative of the local chord moment for the brace in question. allowable axial stress in compression (FA).1-3 0.3.L= 4243. mm ) Chord Memb : D = 406.0.7.2 FCY= 186.Pro .0 or TRACK 2.1-3 0.0 output: (BRITISH SECTIONS) PASS API 3.0 (BRITISH SECTIONS) PASS API 3.00 5.40 T = 10.3 | |-------------------------------------------------------------------------| 14 ST PIP1938.2 | | FTZ= 186.9 FV= 99.29 4. UNIT NEW-MMS .00 0. SZ= 208157.16 C 0.078 2 98.130 2 67.3. 22A.6 CB= 1.21 ALLOWABLE STRESSES: FCZ= 186.24 |-------------------------------------------------------------------------| | MEMB= 14.00 YLD= 248.0 output: STAAD. AX= 4670.API JOINT CHECKS TO 21st edition. --------------------------------------------------7 CHORD NO: 7 BRACE NO: 10 RATIO: 7 CHORD NO: 7 BRACE NO: 13 RATIO: 7 CHORD NO: 11 BRACE NO: 14 RATIO: NODE NO: NODE NO: NODE NO: 0.KN METE (UNLESS OTHERWISE NOTED) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 6 ST PIP40610.00 For TRACK 1.0 output: STAAD.01 830 — STAAD.12 3.2 FTY= 186.Pro .024 2 2. SY= 208157.| | KL/R-Y= 64.0 output: STAAD. the program will block out part of the table and will print the allowable bending stressed in compression (FCY & FCZ) and tension (FTY & FTZ).0 22A. --------------------------------------------------====================================================================== NODE NO : 7 CHORD NO: 7 BRACE NO: 13 ====================================================================== DESIGN DATA : (Units : N .API JOINT CHECKS TO 21st edition.(API ) *********************** PROGRAM CODE REVISION V21_API_2000/1 ALL UNITS ARE . and allowable shear stress (FV).12 0.Pro .00 5.1 Example of Member Code Check output For TRACK 0.6 FT= 148.Section 22 Steel Design per American Petroleum Institute Code Note: If the parameter TRACK is set to 1.2 Example of Joint Check output For TRACK 0.0 (BRITISH SECTIONS) PASS API 3.2 FA= 117.Pro CODE CHECKING .3.7.1-2 0.245 0.76 T 0.222 PASS PASS PASS For TRACK 2.00 7 ST PIP40610.14 C 0.049 0. 983 0. When the file is created for the first time by the program. Other types of joints (such as grouted joints.PUN).% X.0 output ------------------------------------------------------------------Joint Load Strength Chord Load C1 C2 C3 Class Cond factor (Qu) factor (Qf) -------------------------------------------------------------------X AX 10.PUN file) are to be in imperial units. m ) (KN.1 that the value of yield stress of the chord member to be used in the calculation of the joint capacity should be limited to 0. the value specified in the FYLD column will be used as the yield strength to be used for the joint capacity checks.80 Fyc = 248. 50.000 0. The program only checks simple joints and overlapping joints formed between circular hollow section members. m ) ---------------------------------------------------------------------AXIAL : 66.995 2 273.989 0.% Y FACTORS : Factors are not displayed for TRACK 1. etc.200 0.3) (KN.) are not considered.00 Angle (THETA) = 45.962 0. Any other type of joint within the structure or joint cans will not be considered for API joint checks.80 JOINT CLASS : X + Y Contributions: 0.30 TAU = 0.Section 22 Steel Design per American Petroleum Institute Code Brace Memb : d = 193. Material Strength The API code states in Cl.000 0. International Design Codes Manual — 831 .% K.8 Joint Design 22A.300 0.398 0.989 0.500 Y AX 14. The yield stress to be used in the joint capacity checks value is specified in the joint data file (filename.080 2 33.800 X IPB 7. 4.48 GAMMA = 20.1 Joint Checking The design of joints is based on Section 4 of the API code.896 0.299 0.200 0.0 deg GAP = 50.228 0. 4.000 0.245 PASS IP BENDING : 0.896 0.200 0.000 0.400 Y IPB 7. For every joint.2. Note: All the fields in the joint data file (*.002 PASS INTERACTION : 2 0.245 PASS ---------------------------------------------------------------------CRITICAL : 2 0.8 times the tensile strength of the chord for materials with a yield stress less than or equal to 500 MPa.70 t = 8.988 0.8. 50.400 ---------------------------------------------------------------------CAPACITY CHECKS BRACE LOAD LC CAPACITY RATIO STATUS (Cl.2 BETA = 0. The value used for each joint check will also be reported in the output file. a default value of 36 ksi is used for all joints. joints with ring stiffeners.245 PASS ---------------------------------------------------------------------- 22A. Since a joint is between a chord and a brace member. and Y components corresponding to the three joint types. the capacity of that joint is then evaluated per Section 4. however. You. If both the diameter and thickness of the members are identical.3 of the code specifies a minimum capacity for any joint as follows: The connections at the ends of a member should develop the strength required by the design loads. The classification of a joint can also be a mixture of any of the basic types mentioned above. The program automatically identifies the joints in a structure and identifies the chord and the brace members. the program will assume the most horizontal member to be the chord. 832 — STAAD.Section 22 Steel Design per American Petroleum Institute Code Minimum Joint Capacity Clause 4.PUN) to add or delete new BRACE-CHORD joints.2. The program also reports a PASS/FAIL status for the joint. the chord is assumed to be the member with the thicker wall. but should not be less than 50% of the effective strength of the member. must ensure that this condition is satisfied even if the joint strength indicates a PASS status. If both members have the same diameter. the program considers two members at a time and then proceeds to identify the chord and the brace member at that joint.3 of the code.4 of the API code essentially classifies a joint into one of the three basic types: K. The program considers any two members to be in the same plane if they lie in planes that are within ±15 degrees of each other. If not the program issues a warning to that effect and marks the joint as FAILED. The program checks to see if the capacity of a joint as calculated by the methods in the code satisfies this requirement. Joint Classification Clause of 4. A joint— as considered in the code—is the connection between a "chord" and a "brace" that are in the same plane.2.PUN file. The user can always edit the joint data file (*. The program applies the ±15° rule to determine the members in a plane and then determines the joint as being the intersection point of these members. Once the classification of a joint has been identified.Pro . and Y. Joint classification is the process whereby the axial load in a given brace is subdivided into its K. See "Simple Joints: Capacity Checks" for details of capacity checks performed. The program assumes the member with the larger diameter among the two members as the chord member and the other is considered as the brace. The program also reports a ‘critical ratio’ along with the condition that induces this ratio. To be automatically considered as a chord member. The chord and brace member numbers (from the STAAD input file) are saved under the CHORD and BRACE columns in the filename. The effective strength is defined as the buckling load for a compression member or the yield load for members in tension. Note that the maximum among the various individual ratios will be reported as the ‘critical ratio’. X. the member has to be continuous across the joint. X. The program calculates the axial and/or bending moment capacities of the joint and reports the load/capacity ratio for each condition. and Y joint classes for a given joint. he/she must make a separate copy of this file before making any changes to the model.0.e.25. 22A. This is indicated by the K. and 50% Y. When the API design module is invoked. the axial load in the through brace will be increased to allow for the loads in the overlapping brace.4 of the API discusses overlapping joints.PUN file (where filename is the name of the . The overlapping brace in this case can then be indicated by specifying the member number at the OBRACE (Overlapping brace) column in the data file. The program will verify that the supplied contributions sum to 1. it will assume that the joint design has been run at least once and will attempt to read the input data from this file.6.std file) in the same folder as the input file.2. the program will initially check for the presence of a filename. X. Since the API code allows for a mixed joint classification. it assumes that the joint design is being run for the first time and will create this file..PUN) is created by the program.50 for that joint.8.25·β·D.Section 22 Steel Design per American Petroleum Institute Code When the joint data file (. 25% X. the gap distance (in inches) must be supplied in the GAP column. then you must assign K column value of 0. Note: Units used in this file must be kips and inches. If the program does find this file. X.. Overlapping Joints Clause 4. and a Y column value of 0.2. Note: The program issues a warning for any joint overlap is less than 0. a K-GAP joint).25. Not that modifying and saving the main structure (i. The value to be provided will be the actual gap between the brace members at the joint. any changes to the main model using GUI or text editor) will invalidate all design results and the program will automatically delete all design related files including the *. g.e. and 1 respectively. 0. If the axial loads in the overlapping brace and the through brace have the same sign.6. This will be achieved by allowing a portion of the overlapping brace load equal to the proportion of the overlapping brace area to be added to the axial load in the through brace.PUN file should meet the following format. Checks for overlapping joints will be performed as described Section 22A. a default joint Class Y is assumed for the initial joint checks. The overall process of performing punching shear checks consists of two steps which are explained in Section 22A. X column value of 0.PUN file. For example. Hence if the user wises to keep an existing version of the *. and Y column values being set to 0. An overlap can be specified by setting the gap to a negative value.2 Joint File Format The data contained in the filename. If the program does not find such a file. you must manually vary the contribution factors for K. International Design Codes Manual — 833 . The difference will be in that the gap value. If the joint has a gap (i. if a joint is to be 25% K. will be taken as negative in evaluating the various factors.PUN file. 626 0.e. Initially.000 16.. SWAP 1 uses the minor moment My as the IPB.000 0.000 0. db.00 0 T 0. fy = the yield stress to be used in the joint capacity checks ob = member number of the overlapping brace in an overlap joint (i.Pro .000 0. K=0. Example *BRACE CHORD T GAP 10 7 16. the value of GAP is assumed as 0.000 0.000 1. tb = Diameter and thickness of BRACE member Dc.00 36.0 0.000 16.000 0.0 0.000 0.626 0.000 16. Tc = Diameter and thickness of CHORD member gap = Distance required to calculate gap factor for K bracing. X%.000 1.Section 22 Steel Design per American Petroleum Institute Code General Format *BRACE CHORD K X Y D T d t GAP FYLD OBRACE TW SWAP b# c# K% X% Y% Dc Tc db tb gap fy ob tw swap Where: b# = the brace member number c# = the chord member number K%. and Y% = The fractional contributions of K-type. taken as the lesser of the weld throat thickness or thickness t of the thinner brace in inches swap = If parameter SWAP 0 is used then major moment Mz is taken for In Plane Bending (IPB).0 0. a gap value less than zero) tw = Used in overlap K-joint.e.00 0 0.315 K X Y D FYLD OBRACE TW SWAP 0.0 0.394 13 7 7.315 14 11 7. An overlap can be specified by setting the gap to a negative value. Initially the joints will be classed as Y (i. X=0 and Y=1).000 0.00 36..394 0. X type and Y-type.0 0. respectively.00 36.00 0 0.394 D 834 — STAAD.394 0.0 0.000 1. Section 23 ANSI/AISC N690 Design Codes International Design Codes Manual — 835 . 836 — STAAD.Pro . 1 of the code. Care should be taken to assign the proper Stainless Steel material properties to the members for the analysis. because this would International Design Codes Manual — 837 . N690 code uses Stainless Steel material in the design. Otherwise.9 is used to calculate allowable compressive stress for Austenitic Stainless Steel. Fabrication and Erection of Steel Safety-Related Structures for Nuclear Facilities (ANSI/AISC N690 1994(R2004)s2). 2 to the Specification of the Design. as per section Q1. if f /F exceeds unity.6F y + SMY fby Fby + SMZ ⋅ fbz Fbz ≤ 1.0 It should be noted that during code checking or member selection. Section Q1.0 when.3 Allowable per AISC-ASD (Ninth Edition) Code of Technical Reference manual except for allowable stress in compression for AUSTENlTlC STAINLESS STEEL.6-1b: SFC − fa 0.0 and Q1. Note: By default. fa/Fa > 0. equation Q1. ANSI/AISC N690-1994 Code STAAD. 23A. Correction made in Supplementary s1 published in April 15. All the design steps are done as described in section 2.6.1 Design Process Members subjected to both axial compression and bending stresses are proportioned to satisfy equation Q1.5. There is a parameter – STYPE – to change material type to either Stainless Steel (STYPE=1) or Carbon Steel (STYPE=0).6-2 must be satisfied: SFC − fa Fa + SMY fby Fby + SMZ ⋅ fbz Fbz ≤ 1. 23A. 2002 has been applied.1. the a a program does not compute the second and third part of the formula.23A.6-1a: SFC − fa Fa + SMY ⋅ C my fby f Fby 1 − a F ′ey + SMZ ⋅ C mzfbz f Fbz1 − a F ′ez ≤ 1. STAAD compares the actual stresses with the allowable stresses as defined by ANSI/AISC N690-1994 and as amended by ANSI/AISC N690 1994(R2004)s2. Design of members per ANSI/AISC N690-1994 requires the STAAD Nuclear Design Codes SELECT Code Pack.1 General Comments For steel design.15.Pro is capable of performing steel design based on ANSI/AISC N690-1994 and as amended by Supplement No. Members subjected to both axial tension and bending stress are proportioned to satisfy equation Q1. Refer to Table 23A. Depending on the particular design requirements for an analysis. 23A.0. and SMY are stress limit coefficient parameters used to control the components of the interaction equations.6F y + SMY fby Fby + SMZ ⋅ fbz Fbz ≤ 1. but not less than 0.0 Where: SFC. The default parameter values have been selected such that they are frequently used numbers for conventional design. SMZ. See section 5. some or all of these parameter values may have to be changed to exactly model the physical structure Table 23A. SFT.2 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.6-3: SFT − fa 0. 838 — STAAD. ANSI/AISC N690-1994 Code result in a misleadingly liberal ratio. Perform design at ends and those locations in the SECTION command.1-Design Parameters for ANSI/AISC N690-1994 Parameter Name CODE Default Value Description Must be specified as AISC N690 Design Code to follow.48.1 for details.4 for no side-sway.Pro . are listed in the following table. Perform design at ends and at 1/12th section locations along the member length. The value of the coefficient Cm is taken as 0.1 of the Technical Reference Manual. 1. These parameter names. with their default values. BEAM 1 Beam parameter 0.6 .85 for sidesway and [0.23A.4·(M1/M2)]. Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2.Parameter Name CAN Default Value 0 Description Used for Deflection Check only (i. 1. CMY CMZ 0. Height of shear connectors after welding (HGT).85 for sidesway and calculated for no sidesway 0 Cm value in local y & z axes COMPOSITE Composite action with connectors (CMP) 0..625 in Diameter of shear connectors (DIA). No composite action 1. when DFF is specified). CONHEIGHT 2. Deflection check based on the principle that maximum deflection is of the cantilever type CB 1.0 Bending coefficient dependent upon moment gradient.5 in CYCLES 500. 0. Ignore positive moments during design CONDIA 0. as specified in Chapter F of AISC ASD. in current units. 0. Composite action 2.0 = CB is calculated itself Any other user-defined value is accepted. in current units.000 International Design Codes Manual — 839 .e. Cycles of maximum stress to which the shear connector is subject (CYC). this is minor axis. in current units. Maximum allowable depth Minimum allowable depth Effective width of concrete slab (WID).0 KY 1.Pro .0 840 — STAAD.23A. in current units. denoting starting point for calculation of "Deflection Length" Joint No. Compressive strength of concrete at 28 days.4 Description "Deflection Length" / Maximum allowable local deflection DJ1 Joint No. ANSI/AISC N690-1994 Code Parameter Name DFF Default Value None (Mandatory for deflection check) Start Joint of member End Joint of member 0. Effective Length Factor for Compression in local y-axis. Usually. denoting end point for calculation of "Deflection Length" Ratio of moment due to dead load applied after the concrete hardens to the total moment (DR2). Yield strength of steel. in current units. FYLD KX 46 KSI 1.0 inch 1/4 Member Length 36 KSI 3 KSI FYLD FPC Yield strength of steel in current units. Ratio of moment due to dead load applied before the concrete hardens to the total moment (DR1).4 DMAX DMIN EFFWIDTH 45 inch 0. False 1. Full section shear for welding. Effective length factor for flexural torsional buckling. DJ2 DLR2 DLRATIO 0. True FSS 1 FU 60 KSI Ultimate tensile strength of steel. 0. 5.0 indicates that no overstressing is allowed. LX Member Length Member Length Member Length 0. in current units. LZ MAIN Design for slenderness: 0. PLTHICK 0 PLTWIDTH 0 PROFILE None RATIO 1. Used to search for the lightest section for the profile(s) specified for member selection.7.0 Description Effective Length Factor for Compression in local z-axis.0 Net section Factor for tension members Factor by which all allowable stresses/capacities should be multiplied. Default of 1.48. See Section 5. Usually. Permissible ratio of the actual to allowable stresses.0 International Design Codes Manual — 841 . suppress slenderness check NSF OVR 1. Height of ribs of form steel deck (RBH). Width of ribs of form steel deck (RBW).0 LY Length to calculate slenderness ratio (KL/r) for buckling about local Y axis. this is major axis. in current units. Width of the cover plate welded to the bottom flange of the composite beam (PLT). check for slenderness 1.0 1. in current units. in current units. Same as above except in z-axis (major). Thickness of the cover plate welded to the bottom flange of the composite beam (PLT). Stress limit coefficient for compression (SLC) as found in Table Q 1. Length for flexural torsional buckling.Parameter Name KZ Default Value 1.0 RIBHEIGHT 0 RIBWIDTH 0 SFC 1.1 of the Technical Reference Manual for details.1. No sidesway SMY 1.5. ANSI/AISC N690-1994 Code Parameter Name SFT Default Value 1. 0. No sidesway STIFF Member length or depth whichever is greater 0.0 SSY 0 SSZ 0 Design for sidesway in the local z axis.0 Spacing of stiffeners for plate girder design.5. Austenitic Stainless Steel 842 — STAAD. in current units. STYPE Type of steel material 0.0 SMZ 1. Stress limit coefficient for major axis bending (SLC) as found in Table Q 1. Stress limit coefficient for minor axis bending (SLC) as found in Table Q 1.7. Sidesway 1. Normal Steel 1. in current units. Design for sidesway in the local y axis. With shoring SLABTHICK 4 in Thickness of concrete slab or thickness of concrete slab above the form steel deck (THK). Computes the actual shear stress using VQ/It 1. Without shoring 1.7. Computes the actual shear stress using V(Ay or Az) SHE 0 SHORING 0 Temporary shoring during construction 0.23A.5.0 Description Stress limit coefficient for tension (SLC) as found in Table Q 1.1. Shear stress calculation option 0.1.1.Pro . Sidesway 1. 0.7. 0. Design for tapered section based on Appendix F. 1. UNT Member Length WELD 1 WMAX 1 in Maximum weld thickness. TRACK 0. Will be used only if flexural compression on the top flange. Minimum detail 1. 1. Do not design for torsion. International Design Codes Manual — 843 . Open sections. TMAIN 240 for main member 300 for “Truss” member Slenderness limit under tension TORSION 0 Design for torsion. 0. Closed sections. Design for torsion.0 Controls the levels of detail to which results are reported.Parameter Name TAPER Default Value 1 Description Design for tapered member. in current units. Intermediate detail level 2. 0. Unsupported length of the top* flange for calculating allowable bending compressive stress. Will be used only if flexural compression on the bottom flange. Design for weld. Maximum detail UNB Member Length Unsupported length of the bottom* flange for calculating allowable bending compressive stress. Design for tapered I-section based on rules in Chapter F and Appendix B. 0. 1. 23A.1 Notes 1. (Kl/r)max = 171.4·Fyld 23A.31 Yield Stress of Steel.3.std Solution Allowable Compressive Stress: Maximum Slenderness Ratio.Pro .Pro 5.1 Example 1 This example is included as C:\SProV8i\STAAD\Examp\N690\N690_case1.2-ANSI-AISC N690-1994 Code Verification Problem 1 Value of F (ks) a Reference 5. in current units.68 Allowable Compressive Stress for Austentic Stainless Steel. parameters DMAX and DMIN are only used with the MEMBER SELECTION command 23A.3 Examples These example problems are included for the verification of design results. WSTR 0.21 STAAD.2. in current units. 23A. (Kl/r)max > Cc Fa = (12π2 E)/[23(Kl/r)max ] = 5. Allowable welding stress. F = 36 ksi y Cc = [(2π2 E)/Fy ]1/2 = 127.21 ksi Comparison Table 23A. All values are entered in the current units 2.22 Difference Negligible Input File STAAD SPACE 844 — STAAD. As. ANSI/AISC N690-1994 Code Parameter Name WMIN Default Value 0.625 in Description Minimum weld thickness. 2 4 0 0.START JOB INFORMATION ENGINEER DATE 30-NOV-07 END JOB INFORMATION INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 0 0 0.5 PERFORM ANALYSIS PRINT STATICS CHECK PRINT ANALYSIS RESULTS UNIT METER KIP PARAMETER 1 CODE AISC N690 TRACK 2 ALL International Design Codes Manual — 845 . MEMBER INCIDENCES 1 1 2.05E+008 POISSON 0.3 DENSITY 76.2E-005 DAMP 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST W6X12 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 PINNED 2 FIXED BUT FX MY MZ LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 MEMBER LOAD 1 CON GY -10 2 UNIT METER KIP UNIT METER KN LOAD 2 LOADTYPE NONE TITLE LOAD CASE 2 JOINT LOAD 2 FX -1 LOAD COMB 3 COMBINATION LOAD CASE 3 1 1.0 2 9. DEFINE MATERIAL START ISOTROPIC STEEL E 2.8195 ALPHA 1. 00 | | CMZ = 0.0 0.PRO CODE CHECKING .00 -0.55 | | * | ST W6X12 | | --Z AY = 1.85 + FTY = 27.07 | | NSF = 1.1 1.23A.Pro .15 | | CB = 1.4 Fey = 4.48 | FCZ = 14.0 7.31 | FA = 5.26 | | (KL/R)max = 171.33 | | * |<---LENGTH (FT)= 13.1 0.85 | L1 L1 FCY = 27.60 | | CMY = 0.0 0.0 0.| |MEMBER 1 * | AISC SECTIONS | | AX = 3.4 | | LOCATION 0.12 --->| RY = 0.25 | |DESIGN CODE * | | | AZ = 1.) FV = 14.90 | | | | MAX FORCE/ MOMENT SUMMARY (KIP-FEET) | | ------------------------| | | | AXIAL SHEAR-Y SHEAR-Z MOMENT-Y MOMENT-Z | | | | VALUE 2.0 ******************************************** |--------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN INCH UNIT | | * |=============================| ===|=== -----------.12 + L1 L1 fa = 0.00 | | FYLD = 36.60 | | UNL = 157.65 | | dff= 0.0 6.50 | | | | 7.31 (WITH LOAD NO.00 +---+---+---+---+---+---+---+---+---+---| fby = 0.00 ABSOLUTE MZ ENVELOPE Fez = 34.( ANSI N690-1994) v1.92 | |************* RZ = 2.50 | |ANSI N690-94* =============================== ===|=== SY = 1.00 + L1 L1 FTZ = 21.50 | | * SZ = 7.00 |L0 L0 fbz = 12.6 | | LOADING 3 1 0 0 1 | | | |**************************************************************************| |* *| |* DESIGN SUMMARY (KIP-FEET) *| |* -------------*| 846 — STAAD.00 | | DFF = 0.4 (KIP-FEET) | |PARAMETER | L1 STRESSES | |IN KIP INCH | IN KIP INCH | |--------------.40 | | fv = 0. ANSI/AISC N690-1994 Code CHECK CODE ALL FINISH Output The corresponding TRACK 2 output is shown below: STAAD.22 | | KL/R-Z= 63.+ L1 L1 -------------| | KL/R-Y= 171.0 0. International Design Codes Manual — 847 .Pro 9. 4 2 0 1.0 Fa = (Fy /2.3.07 ksi Comparison Table 23A.65 Yield Stress of Steel.0]/120.56 | |* *| |**************************************************************************| | | |--------------------------------------------------------------------------| 23A.00 -7.14 C 0.07 STAAD.0}x(Kl/r)max = 9. (Kl/r)max < 120.15) .6-2 0.15) .std Solution Allowable Compressive Stress: Maximum Slenderness Ratio.{[(Fy /2. F = 36 ksi y Cc = [(2π2 E)/Fy ]1/2 = 127.6. (Kl/r)max = 85. As.|* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS ANSI Q1.3-ANSI-AISC N690-1994 Code Verification Problem 2 Value of F (ks) a Reference 9.38 6.08 Difference Negligible Input File STAAD SPACE START JOB INFORMATION ENGINEER DATE 30-NOV-07 END JOB INFORMATION INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 3 0 0 1.68 Allowable Compressive Stress for Austentic Stainless Steel.968 3 | | 2.2 Example 2 This example is included as C:\SProV8i\STAAD\Examp\N690\N690_case2. ANSI/AISC N690-1994 Code MEMBER INCIDENCES 2 3 4.0 2 9.23A.0 848 — STAAD. DEFINE MATERIAL START ISOTROPIC STEEL E 2.Pro .2E-005 DAMP 0.PRO CODE CHECKING .5 PERFORM ANALYSIS PRINT STATICS CHECK PRINT ANALYSIS RESULTS UNIT METER KIP PARAMETER 1 CODE AISC N690 TRACK 2 ALL CHECK CODE ALL FINISH Output The corresponding TRACK 2 output is shown below: STAAD.8195 ALPHA 1.24809 1 UNIT METER KN LOAD 2 LOADTYPE NONE TITLE LOAD CASE 2 JOINT LOAD 4 FX -1 LOAD COMB 3 COMBINATION LOAD CASE 3 1 1.( ANSI N690-1994) v1.3 DENSITY 76.05E+008 POISSON 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 2 TABLE ST W6X12 CONSTANTS MATERIAL STEEL ALL SUPPORTS 3 PINNED 4 FIXED BUT FX MY MZ LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 MEMBER LOAD UNIT METER KIP 2 CON GY -2. 33 | | * |<---LENGTH (FT)= 6.******************************************** |--------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN INCH UNIT | | * |=============================| ===|=== -----------.05 | | (KL/R)max = 85.60 | | dff= 0.0 0.50 | | * SZ = 7.00 +---+---+---+---+---+---+---+---+---+---| fby = 0.92 | |************* RZ = 2.0 0.346 3 | | 2.0 0.7 (KIP-FEET) | |PARAMETER | L1 STRESSES | |IN KIP INCH | IN KIP INCH | |--------------.14 C 0.1 1.00 | | CMZ = 0.7 | | LOCATION 0.69 3.00 -3.28 | |* *| |**************************************************************************| | | |--------------------------------------------------------------------------| International Design Codes Manual — 849 .60 | | CMY = 0.85 | L1 FCY = 27.00 | | DFF = 0.0 0.90 | | | | MAX FORCE/ MOMENT SUMMARY (KIP-FEET) | | ------------------------| | | | AXIAL SHEAR-Y SHEAR-Z MOMENT-Y MOMENT-Z | | | | VALUE 2.2 Fey = 18.00 -0.00 |L0 L0 fbz = 6.+ L1 L1 -------------| | KL/R-Y= 85.65 | FA = 9.56 --->| RY = 0.56 + L1 fa = 0.0 3.00 + L1 L1 FTZ = 21.08 | | KL/R-Z= 31.00 | | FYLD = 36.40 | | fv = 0.60 | | UNL = 78.25 | |DESIGN CODE * | | | AZ = 1.1 0.65 (WITH LOAD NO.) FV = 14.60 | | CB = 1.50 | | | | 3.0 3.85 + L1 FTY = 27.3 | | LOADING 3 1 0 0 1 | | | |**************************************************************************| |* *| |* DESIGN SUMMARY (KIP-FEET) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS ANSI Q1.55 | | * | ST W6X12 | | --Z AY = 1.6-2 0.04 | | NSF = 1.50 | |ANSI N690-94* =============================== ===|=== SY = 1.00 ABSOLUTE MZ ENVELOPE Fez = 137.| |MEMBER 2 * | AISC SECTIONS | | AX = 3.74 | L1 FCZ = 21. 8195 850 — STAAD.08 Difference None Input File STAAD SPACE START JOB INFORMATION ENGINEER DATE 30-NOV-07 END JOB INFORMATION INPUT WIDTH 79 UNIT METER KN JOINT COORDINATES 1 0 0 0.05E+008 POISSON 0.Pro .3 Example 3 This example is included as C:\SProV8i\STAAD\Examp\N690\N690_case3.3 DENSITY 76. ANSI/AISC N690-1994 Code 23A. As. DEFINE MATERIAL START ISOTROPIC STEEL E 2. 120. 2 2.std Solution Allowable Compressive Stress: Maximum Slenderness Ratio.06 Yield Stress of Steel.68 Allowable Compressive Stress for Austentic Stainless Steel.08 STAAD. (Kl/r)max = 122.08 ksi Comparison Table 23A.Pro 7.4-ANSI-AISC N690-1994 Code Verification Problem 3 Value of F (ks) a Reference 7.(1/600)x(Kl/r)max ] = 7. F = 36 ksi y Cc = [(2π2 E)/Fy ]1/2 = 127. MEMBER INCIDENCES 1 1 2.0 < (Kl/r)max < Cc Fa = Fy [0.4 .85 0 0.23A.3. 0 ******************************************** |--------------------------------------------------------------------------| | Y PROPERTIES | |************* | IN INCH UNIT | | * |=============================| ===|=== -----------.50 | International Design Codes Manual — 851 .03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST W6X12 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 PINNED 2 FIXED BUT FX MY MZ LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 MEMBER LOAD 1 CON GY -10 2 UNIT METER KIP UNIT METER KN LOAD 2 LOADTYPE NONE TITLE LOAD CASE 2 JOINT LOAD 2 FX -1 LOAD COMB 3 COMBINATION LOAD CASE 3 1 1.55 | | * | ST W6X12 | | --Z AY = 1.25 | |DESIGN CODE * | | | AZ = 1.5 PERFORM ANALYSIS PRINT STATICS CHECK PRINT ANALYSIS RESULTS UNIT METER KIP PARAMETER 1 CODE AISC N690 TRACK 2 ALL CHECK CODE ALL FINISH Output The corresponding TRACK 2 output is shown below: STAAD.2E-005 DAMP 0.( ANSI N690-1994) v1.ALPHA 1.0 2 9.PRO CODE CHECKING .| |MEMBER 1 * | AISC SECTIONS | | AX = 3.50 | |ANSI N690-94* =============================== ===|=== SY = 1. 14 C 0.0 6.92 | |************* RZ = 2.00 + L1 L1 FTZ = 21.00 ABSOLUTE MZ ENVELOPE Fez = 67.50 | | | | 4.2 | | LOADING 3 1 0 0 1 | | | |**************************************************************************| |* *| |* DESIGN SUMMARY (KIP-FEET) *| |* -------------*| |* *| |* RESULT/ CRITICAL COND/ RATIO/ LOADING/ *| | FX MY MZ LOCATION | | ====================================================== | | PASS ANSI Q1.40 | | fv = 0.0 0.86 | | CB = 1.2 (KIP-FEET) | |PARAMETER | L1 STRESSES | |IN KIP INCH | L1 IN KIP INCH | |--------------.06 (WITH LOAD NO.60 | | UNL = 112.0 0.00 +---+---+---+---+---+---+---+---+---+---| fby = 0.16 | | dff= 0.0 0.) FV = 14.6-2 0.00 -4.0 7.00 -0.2 Fey = 9.60 | | CMY = 0.33 | | * |<---LENGTH (FT)= 9.+ L1 -------------| | KL/R-Y= 122.6 0.Pro .0 4.08 | | KL/R-Z= 44.429 3 | | 2.00 | | DFF = 0. ANSI/AISC N690-1994 Code | * SZ = 7.84 | | NSF = 1.85 | L1 FCY = 27.2 | | LOCATION 0.00 | | FYLD = 36.06 | L1 FA = 7.00 |L0 L0 fbz = 6.97 + L1 fa = 0.18 6.35 --->| RY = 0.23 | |* *| |**************************************************************************| | | |--------------------------------------------------------------------------| 852 — STAAD.49 | | (KL/R)max = 122.00 | | CMZ = 0.23A.54 | | | | MAX FORCE/ MOMENT SUMMARY (KIP-FEET) | | ------------------------| | | | AXIAL SHEAR-Y SHEAR-Z MOMENT-Y MOMENT-Z | | | | VALUE 2.85 + L1 FTY = 27.1 1.20 | FCZ = 19. Ae = Ct·An Unless otherwise specified.2. shall be computed from the formula (ref.2. the default value of the CT parameter is set as 0.8. And the maximum allowable slenderness ratio in Tension (L/r_ min) shall not exceed 240 for main members and 300 for bracing members and other secondary members.14. and Erection.2 Design Process The following Checks are to be performed on a Steel Member as per this AISC N690 – 1984 Code. Q1.4 of the code shall not exceed 200.2.14). The permissible Width–Thickness Ratio of web is determined as per section Q1.2 Check for Element Slenderness and Stress Reduction Factors The permissible Width-to-Thickness Ratio of “Un-stiffened Elements under Compression” is determined as per section Q1. 23B. as per clause Q1.75.1 General Comments For code checking of steel members.2. The Net Area (An) shall be determined in accordance with Q1. the output file the reports the maximum utilization from all of the checks. This can be controlled by using the existing MAIN and TMAIN parameters respectively.Steel Safety-Related Structures for Design.1. 23B.9. The default value of MAIN is 200 and for TMAIN is 240. The Effective Net Area (Ae) of axially loaded tension members.23B.5.5·Fu on the Effective Net area. where the load is transmitted by bolts through some but not all of the cross-sectional elements of the member.2 of the code. 23B.10." A brief description of some of the major allowable stresses is described herein. as per section Q1. and the NSF parameter can be utilized for that.1 Slenderness The maximum allowable slenderness ratio in Compression (K·L/r_min).1.9.3 Tension Allowable tensile stress on the Net section is calculated as 0.60·Fy . Fabrication. STAAD compares the actual stresses with the allowable stresses as defined by the "ANSI/AISC N690-1984: Nuclear Facilities . ANSI/AISC N690-1984 Code 23B. When a design is performed. but not more than 0. International Design Codes Manual — 853 .1 and that of “Stiffened Elements under Compression” is determined as per section Q1. 23B. e 1.9. Gross Sections of Columns.[(Fy /2. When (Kl/r) > Cc. The allowable compressive stress for columns fabricated from austenitic stainless steel shall be in accordance to section Q1. When (Kl/r) > 120. On gross section of axially loaded compression members. Fa = Fy /2.2.(KL/r)/20 If the provisions of the section Q1. For stiffened compression element. except those fabricated of austenitic stainless steel: 1.23B. Gross sections of columns fabricated from Austenitic Stainless steel: 1. Fa = 12·π2 E/[23(kL/r)2 ] B. When (Kl/r) ≤ 120.14.5. For other uniformly compressed elements: be = 253·t/√Fy {1 .3/[(b/t)√Fy ]} ≤ b 2. Fa = [1 .15 . except those fabricated from austenitic stainless steel shall be as required by Q1.1. A.6)/120](kL/r) 2.(Kl/r)2 /(2·Cc2 )]Fy / {5/3 + [3(Kl/r)/(8·Cc)] .[(Kl/r)3 /(8·Cc3 )]} Where: Cc = [(2·π2 E)/Fy ]1/2 2. a reduced effective width b is introduced.16 .(50.9.9 are not satisfied. 23B. when (Kl/r) ≤ Cc. For the flanges of square and rectangular sections of uniform thickness: be = 253·t/√Fy {1 . a reduction factor Q is introduced and is equal to the effective a area divided by the actual area. Fa = 12 .3/[(b/t)√Fy ]} ≤ b Consequently.5.(44. The provisions for Pin-connected and Threaded tensile member are not implemented in STAAD. B. For un-stiffened compression element.3.Pro . ANSI/AISC N690-1984 Code The value of CT parameter for other conditions is described at section Q1. a reduction factor Q is introduced. Detailed s values of Qs for different shapes are given in Section QC2. Combining both these factors. allowable stress 854 — STAAD.4 Compression The allowable compressive stress for columns which meet the provisions of section Q1. A. 5.75·Fy International Design Codes Manual — 855 . 3.4.4.5.5. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√Fy .for axially loaded compression members containing stiffened or unstiffened elements shall not exceed Fa = QsQa[1 . Along Major Axis: 1.1.16 d/t = 257/√Fy when fa/Fy > 0.60·Fy B. maximum tensile and compressive bending stress shall not exceed the following value as per section Q1. 2.5 Bending Stress Allowable bending stress for tension and compression for a structural member.5.1.1.[(Kl/r)3 /(8·Cc3 )]} Where: C'c = [(2·π2 E)/(QsQaFy )]1/2 23B.(Kl/r)2 /(2·Cc2 )]Fy / {5/3 + [3(Kl/r)/(8·Cc)] .1. maximum bending stress is: Fb = 0.4.1. section Q1. Tension and compression on extreme fibers of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection Q1.5. For doubly symmetrical members (I shaped) meeting the requirements of section Q1. Along Minor Axis: 1. shall result in a maximum bending stress: Fb = 0.2 is followed. b.1 to 7.3: Fb = 0.1. For box-type flexural members.2. The laterally unsupported length of the compression flange of members other than box-shaped members shall not exceed the value of 76bf/√Fy nor 20000/(d/Af)Fy .66·Fy If meeting the requirements of this member of: a.4. The depth-thickness ratio of the web shall not exceed d/t = (640/√Fy )[1 – 3.4 is: A. c.1. as given in section Q1.74(fa/Fy )] when fa/Fy ≤0. Width-thickness ratio of unstiffened projecting elements of the compression flange shall not exceed 65/√Fy . For noncompact and slender elements.16 d. maximum tensile and compressive bending stress shall not exceed: Fb = Fy [0.2.000·k)/[Fy (h/t)2 ]. SMZ.0 For actual shear on the web.34/(a/h)2 ].4 for no side-sway.10.0 and Q1. 856 — STAAD.6·Fy ) + SMY·fby /Fby + SMZ·fbz/Fbz ≤ 1.6.1 of the code.1 for details.002(bf/2tf)√Fy ] 23B.4·(M1/M2)].8 k = 4.5. the a a program does not compute the second and third part of the formula. if f /F exceeds unity.0 Where SFC.4.8 Cv = [190/(h/t)]√(k/Fy ). when h/t > 0.34 + [4. when a/h > 1.1. the gross section is taken as the total flange areas. SFT. For doubly symmetrical members (I shaped) meeting the requirements of section Q1.6 .0.6-1b: SFT·fa/(0.6-1b SFC·fa/(0. Members subjected to both axial tension and bending stress are proportioned to satisfy equation Q 1. except where bf/2tf > 65/√Fy but is less than 95/√Fy . the gross section is taken as the product of the total depth and the web thickness. ANSI/AISC N690-1984 Code 2. but not less than 0.0 when. fa/Fa > 0. section Q1.85 for sidesway and [0.00 + [5.7 Shear Stress Allowable shear stress on the gross section [ref.0 k = 5.1.Pro . when a/h ≤ 1. For shear on the flanges.6 Combined Interaction Check Members subjected to both axial compression and bending stresses are proportioned to satisfy equation Q1.4·Fy Where: Cv = (45.6·Fy ) + SMY·fby /Fby + SMZ·fbz/Fbz ≤ 1.fa/F'ey )Fby ] + SMZ·Cmzfbz/[(1 . because this would result in a misleadingly liberal ratio.2] is calculated as Fv = (Fy /2. 23B.2. equation Q1.79 – 0.89)Cv ≤ 0. The value of the coefficient Cm is taken as 0.0 It should be noted that during code checking or member selection.fa/F'ez)Fbz] ≤ 1.5.6-2 must be satisfied: SFC·fa/Fa + SMY·fby /Fby + SMZ·fbz/Fbz ≤ 1. Otherwise. as per section Q1.00/(a/h)2 ]. when h/t ≤ 0. and SMY are stress limit coefficient parameters used to control the components of the interaction equations.23B.15.6-1a: SFC·fa/Fa + SMY·Cmy fby /[(1 . Refer to Table 17B. and Double Channel sections.23B. Member properties may also be specified using the User Table facility except for the General and Prismatic member. Depending on the particular design requirements for an analysis. Channel. 0 = Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2.1 of the Technical Reference Manual. namely: I-shaped section. Tee. are listed in the following table. some or all of these parameter values may have to be changed to exactly model the physical structure Table 23B. refer to Section 1. 1 = Deflection check based on the principle that maximum deflection is of the cantilever type International Design Codes Manual — 857 .48. These parameter names. HSS Tube. 23B. with their default values. CAN 0 Used for Deflection Check only. Double Angle. Angle. HSS Pipe. the specified steel section available in Steel Section Library of STAAD may be used. See section 5.3 Member Property Specification For specification of member properties. Design Code to follow.7 the STAAD Technical Reference Manual.4 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.1-Design Parameters for ANSI/AISC N690-1984 Parameter Name CODE Default Value Description Must be specified as AISC N690 1984 to use the ANSI/AISC N690-1984 code for checking purposes. For more information on these facilities. The default parameter values have been selected such that they are frequently used numbers for conventional design. Effective Length Factor for Compression in local z-axis. "Deflection Length" / Maximum allowable local deflection DFF None (Mandatory for deflection check) Start Joint of member End Joint of member 45 inch 0. ANSI/AISC N690-1984 Code Parameter Name CB Default Value 1. DJ2 DMAX DMIN FU FYLD KY 36 KSI 1. denoting starting point for calculation of "Deflection Length" Joint No. Yield strength of steel in current units.75 Cm value in local y & z axes CT Reduction Coefficient in computing net effective net area of an axially loaded tension member. denoting end point for calculation of "Deflection Length" Maximum allowable depth Minimum allowable depth Ultimate tensile strength of steel in current units. this is minor axis. Length to calculate slenderness ratio for buckling about local Y axis. Usually.0 LY Member Length 858 — STAAD. Usually.85 for sidesway and calculated for no sidesway 0. this is major axis.0 Description Bending coefficient dependent upon moment gradient 0.0 inch 60 KSI DJ1 Joint No.23B.0 KZ 1.Pro . CMY CMZ 0. Effective Length Factor for Compression in local y-axis.0 = CB is calculated itself Any other user-defined value is accepted. 0 SMY 1.0 STIFF Member Spacing of stiffeners for plate girder design length or depth whichever is greater 0.0 = Austenitic Stainless Steel STYPE TMAIN 240 for main member 300 for “Truss” member Slenderness limit under tension International Design Codes Manual — 859 .0 SFC 1.1 of the Technical Reference Manual for details.5.0 Description Same as above except in z-axis (major). Check for slenderness 1.7. RATIO 1. Stress limit coefficient for minor axis bending (SLC) as found in Table Q 1.0 SMZ 1.1. See Section 5.7.48.5.1.1. Stress limit coefficient for tension (SLC) as found in Table Q 1.7.0 = Normal Steel 1.5.Parameter Name LZ Default Value Member Length 0.0 SFT 1. Stress limit coefficient for compression (SLC) as found in Table Q 1.0 0. 0. Suppress slenderness check NSF PROFILE 1.1. MAIN Design for slenderness. Permissible ratio of the actual to allowable stresses.7. Stress limit coefficient for major axis bending (SLC) as found in Table Q 1.0 None Net section Factor for tension members Used to search for the lightest section for the profile(s) specified for member selection.5. std 860 — STAAD. Refer to Section 5.23B.4. UNT Member Length 23B. Unsupported length of the top* flange for calculating allowable bending compressive stress. All values are entered in the current units 2.1 .48.5 of the Technical Reference Manual for general information on Code Checking. 23B. Will be used only if flexural compression on the top flange. Refer to Section 2. 0 = Minimum detail 1 = Intermediate detail level 2 = Maximum detail UNB Member Length Unsupported length of the bottom* flange for calculating allowable bending compressive stress.5 Code Checking and Member Selection Both code checking and member selection options are available with the AISC N690 1984 code. Will be used only if flexural compression on the bottom flange. Refer to Section 2. parameters DMAX and DMIN are only used with the MEMBER SELECTION command 23B.6 of the Technical Reference Manual for general information on Member Selection. 23B.Pipe Section This example is included as C:\SProV8i\STAAD\Examp\nuclear code samples\N690_1984_ Pipe_Section.3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 5.0 Description Controls the levels of detail to which results are reported. ANSI/AISC N690-1984 Code Parameter Name TRACK Default Value 0.48.6.2 of the Technical Reference Manual for details the specification of the Code Checking command.1 Notes 1.6 Examples These example problems are included for the verification of design results.Example 1 .Pro . Load Case 2: Compression-only Allowable Compressive Stress: Maximum Slenderness Ratio.2 = 3.26 in.88 in.83) 2 2 3 3 = 36ksi 2(127.60 ksi = 0.0(10 ft)(12 ft/in. Solution Section Properties: Ax = 4.75(4.30 in. = 63.0 − 5 3 ( Kl / r) 2 2C c 2 1. 0.0.3 Load Case 1: Tension-only Allowable Tensile Stress: Ft = min(0.20/4. t = 0. Schedule 40 Pipe section made from Grade 36 steel. Sx = Sy = 15.4 ·2/5.Problem A 10 ft long simply supported beam subject to axial (+/. OK. (Kl/r)max = 1.0 − 3 (63.83 < 200.23 in.6·Fy .4 r = (15.144 < 1.20 in.68) − (63. = 5.2 ) = 3.468 in. OK.D. Yield Stress of Steel.10 ksi Stress Ratio = 3.56 in.2 ft = 10 kip/ 3.06ksi 8(127. F = 36 ksi y Cc = [(2π2 E)/Fy ]1/2 = 127.23 in. = 5.68) 5 3 + 3( Kl / r) 8C c − ( Kl / r) 3 8C c + 3(63.30)1/2 = 1.60 ksi Actual Tensile Stress: ft = P/Ae Where: Ae = Ct·An = 0.68) International Design Codes Manual — 861 ..)/1. The beam is a 5" diameter.68 (Kl/r)max < Cc Fc = Fy 1.10 kip) and bending loads (3 kip/ft) in both the local y and z axis.10 ksi/21.83) 8(127. O.2 Iy = Iz = 15.83) = 17.88in.30 in.20 in.6(36 ksi) = 21.5·Fu ) = 0.56 in. CT = 1. CT = 1.Pro .815 2. Load Case 3: Tension + Bending Allowable Bending Stress: Fby = Fbz = 0.853 0.136 + 0.76 ksi Actual Bending Stress (include member selfweight in Y dir.0.6(36 ksi)] + 0.845 0.0./ft) = 47.2 = 2.66(36 ksi) = 23.136 < 0.144 0.0 Stress Ratio = 8.108 STAAD.63 ksi fbz = 45.844 Negligible 0.0 in·kip fby = 47.06 ksi = 0./ft) = 45.76 ksi = 0.346 = 0.30 in.33 ksi/17.3 kip/ft (10 ft)2 /8 (12 in.23 ksi/ 23.3 = 8.468 in.845 < 1.468 in.66·Fy = 0.2 in·kip Mz = 0. OK.136 None Reference 0.10 ksi/[0. ANSI/AISC N690-1984 Code Actual Compressive Stress: fa = 10 kip/4.136 < 1.): My = 0.363 < 1.315 kip/ft (10 ft)2 /8 (12 in.0) Compression + Bending 0.3 = 8.346 = 0.76 ksi = 0.2-ANSI/AISC N690-1984 Code Verification Problem 1 Condition Tension (0.23 ksi Stress Ratio = 8.23B.136 0.63 ksi/ 23.0 in·kip/5.346 < 1.107.6·Fy ) + fby /Fby + fbz/Fbz = 3.0 Combined Stress Check: fa/(0.853 Load Case 4: Compression + Bending Combined Stress Check: fa/Fa = 0.817.0) Compression Tension + Bending (0.Pro Difference 862 — STAAD.51% 0. OK Comparison Table 23B.2 in·kip/5.33 ksi Stress Ratio = 2.363 + 0.15 fa/Fa + fby /Fby + fbz/Fbz = 0.363 + 0. 489024 ALPHA 1.3 DENSITY 0. MEMBER INCIDENCES 1 1 2.Input File STAAD SPACE START JOB INFORMATION ENGINEER DATE 09-DEC-09 END JOB INFORMATION INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES 1 0 0 0.3 International Design Codes Manual — 863 .2E-005 DAMP 0. 2 10 0 0.03 END DEFINE MATERIAL UNIT INCHES KIP MEMBER PROPERTY AMERICAN 1 TABLE ST PIPS50 UNIT FEET KIP CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 PINNED 2 FIXED BUT FX LOAD 1 TENSION ONLY JOINT LOAD 2 FX 10 LOAD 2 COMPRESSION ONLY JOINT LOAD 2 FX -10 LOAD 3 TENSION+BENDING SELFWEIGHT Y -1 MEMBER LOAD 1 UNI GY -0. DEFINE MATERIAL START ISOTROPIC STEEL E 4.176E+006 POISSON 0. 3 JOINT LOAD 2 FX -10 MEMBER LOAD 1 UNI GZ 0.3 LOAD 4 COMPRESSION+BENDING SELFWEIGHT Y -1 MEMBER LOAD 1 UNI GY -0.3 PERFORM ANALYSIS PRINT LOAD DATA PRINT MEMBER PROPERTIES ALL UNIT INCHES KIP LOAD LIST 1 PARAMETER 1 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 30 ALL UNT 30 ALL CT 0.23B. ANSI/AISC N690-1984 Code JOINT LOAD 2 FX 10 MEMBER LOAD 1 UNI GZ 0.75 ALL CHECK CODE ALL ** FOLLOWING TO CHECK IF THE NET AREA IS USED IN CALCULATING TENSILE STRESS PARAMETER 11 CODE AISC N690 1984 FU 40 ALL CHECK CODE ALL 864 — STAAD.Pro . 75 ALL CHECK CODE ALL LOAD LIST 3 PARAMETER 3 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 30 ALL UNT 30 ALL CT 0.LOAD LIST 2 PARAMETER 2 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 30 ALL UNT 30 ALL CT 0.75 ALL CHECK CODE ALL International Design Codes Manual — 865 . Pro .23B.75 ALL CHECK CODE ALL LOAD LIST ALL PARAMETER 5 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 30 ALL UNT 30 ALL CT 0.75 ALL CHECK CODE ALL 866 — STAAD. ANSI/AISC N690-1984 Code LOAD LIST 4 PARAMETER 4 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 30 ALL UNT 30 ALL CT 0. 46 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .844 4 10.60 CMY: 0.30 AYY: 2.38E+01 FCY: 2.00 C 44.FINISH Output The TRACK 2 output for the final parameter set is shown here: STAAD.00 | | CT: 0.0 CMZ: 0.KIP INCH) | | AXIAL: 1.88 | | SZZ: 5.60E+00 FBY: 8.71E+01 FCZ: 2.44E+01 | | ACTUAL STRESSES: (UNIT .75 STEEL TYPE: 0.KIP INCH) | | KL/R-Z: 63.46 SYY: 5.20E+00 SHEAR: 9.PRO CODE CHECKING .0 ******************************************** ALL UNITS ARE .83 ALLOWABLE RATIO: 200.INCH) | | AXX: 4.88 RYY: 1.84 47.00 | | ALLOWABLE STRESSES: (UNIT .00 FYLD: 36.83 KL/R-Y: 63.6-Eqn 2 0.83 UNL: 30.12E-01 | |----------------------------------------------------------------------------| | SECTION PROPERTIES: (UNIT .38E+01 FTY: 2.00 FU: 58.KIP INCH) | | AXIAL: 2.33E+00 FBZ: 8.0 | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | International Design Codes Manual — 867 .00 |----------------------------------------------------------------------------| | SLENDERNESS CHECK: ACTUAL RATIO: 63.27 AZZ: 2.27 RZZ: 1.60 | | CB: 1.( AISC N690 1984) v1.02 120.00 NET SECTION FACTOR: 1.38E+01 FTZ: 2.KIP INCH (UNLESS OTHERWISE NOTED) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST PIPS50 (AISC SECTIONS) PASS Q1.38E+01 | | SHEAR: 1. 060 3 1.00E+01 4.03 in.22 ksi Stress Ratio = 9.136 2 1.4 in·kip/7.00E+01 | | COMPRESSION 0.230 in.063 3 1./ft) = 67.23B.Pro . The beam is a W6x12 section made from Grade 36 steel.2 d = 6.312 kip/ft (12 ft)2 /8 (12 in.87E+00 | |----------------------------------------------------------------------------| 23B.108 1 1.00E+01 4.31 in. ANSI/AISC N690-1984 Code | CLAUSE RATIO LOAD FX VY VZ MZ MY | | TENSION 0.96E+00 | | SHEAR-Z 0.66(36 ksi) = 23.31 in.22 ksi/ 23. tw = 0.76 ksi = 0.55 in.3 Allowable Bending Stress: Fbz = 0.4(36 ksi) = 14.70E+01 4.4·Fy = 0.48E+01 | | TEN&BEND 0.W-Section This example is included as C:\SProV8i\STAAD\Examp\nuclear code samples\N690_1984_ W-Section.2 Example 2 .): Mz = 0.48E+01 | | SHEAR-Y 0.815 3 1.844 4 1.4 in·kip fbz = 67. Solution Section Properties: A = 3.40 ksi Actual Shear Stress: 868 — STAAD. OK Allowable Shear Stress: Fv = 0.70E+01 4.0.66·Fy = 0. Sz = 7.00E+01 | | COMP&BEND 0.3 = 9.76 ksi Actual Bending Stress (include member selfweight in Y dir.6.std Problem A 12 ft long simply supported beam subject to uniform load (3 kip/ft).388 < 1. 094 Difference Negligible None Input File STAAD SPACE START JOB INFORMATION ENGINEER DATE 09-DEC-09 END JOB INFORMATION INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES 1 0 0 0.Vz = 0.5(12 ft)(0.489024 ALPHA 1.3 DENSITY 0.094 STAAD.2E-005 DAMP 0.) = 1.872 kip fvz = 1. Comparison Table 23B.40 ksi = 0. x 0.3-ANSI/AISC N690-1984 Code Verification Problem 3 Condition Bending Shear Reference 0.35 ksi Stress Ratio = 1.387 0.176E+006 POISSON 0.312 kip/ft) = 1. MEMBER INCIDENCES 1 1 2.388 0.872 kip/(6. OK.Pro 0.0.03 in.35 ksi/ 14.094 < 1.230 in.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST W6X12 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 2 PINNED LOAD 1 LOADTYPE NONE TITLE LOAD CASE 1 International Design Codes Manual — 869 . 2 12 0 0. DEFINE MATERIAL START ISOTROPIC STEEL E 4. 23B.40 72.3 PERFORM ANALYSIS PRINT LOAD DATA PRINT MEMBER PROPERTIES ALL *UNIT KIP INCH PARAMETER 1 CODE AISC N690 1984 CB 1 ALL CMY 0 ALL CMZ 0 ALL * 36 & 58 FYLD 36 ALL FU 58 ALL KY 1 ALL KZ 1 ALL MAIN 200 ALL NSF 1 ALL RATIO 1 ALL TMAIN 300 ALL TRACK 2 ALL UNB 3 ALL UNT 3 ALL UNIT KIP INCH CHECK CODE ALL FINISH Output The TRACK 2 output for the final parameter set is shown here: STAAD.00 -67.Pro .00 |----------------------------------------------------------------------------| 870 — STAAD.0 ALL UNITS ARE .387 1 0.PRO CODE CHECKING .KIP MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST W6X12 (AISC SECTIONS) PASS Q1.00 T 0.6-Eqn 2 0.( AISC N690 1984) ******************************************** INCH (UNLESS OTHERWISE NOTED) v1. ANSI/AISC N690-1984 Code SELFWEIGHT Y -1 ALL MEMBER LOAD 1 UNI GY -0. 00E+00 | | TEN&BEND 0.00E+00 | | COMP&BEND 0.92 | | SZZ: 7.094 1 1.INCH) | | AXX: 3.000 1 0.00 FU: 58.50 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .KIP INCH) | | AXIAL: 0.70E+01 FTZ: 2.39 AZZ: 1.60 | | CB: 1.00 FYLD: 36.70E+01 | | SHEAR: 1.75 STEEL TYPE: 0.64 UNL: 36.00E+00 | | COMPRESSION 0.64 ALLOWABLE RATIO: 300.00 | | CT: 0.50 RYY: 0.| SLENDERNESS CHECK: ACTUAL RATIO: 156.38E+01 FTY: 2.0 CMZ: 0.00E+00 | | SHEAR-Y 0.87E+00 | | SHEAR-Z 0.20E+00 FBY: 0.00E+00 SHEAR: 0.KIP INCH) | | AXIAL: 6.74E+01 0.00E+00 FBZ: 9.00E+00 | |----------------------------------------------------------------------------| International Design Codes Manual — 871 .0 | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | | CLAUSE RATIO LOAD FX VY VZ MZ MY | | TENSION 0.55 AYY: 1.00E+00 | |----------------------------------------------------------------------------| | SECTION PROPERTIES: (UNIT .60 CMY: 0.KIP INCH) | | KL/R-Z: 57.000 1 0.000 1 0.00 | | ALLOWABLE STRESSES: (UNIT .74E+01 0.38E+01 FCY: 2.000 1 0.00 NET SECTION FACTOR: 1.387 1 0.00E+00 6.44E+01 | | ACTUAL STRESSES: (UNIT .33 SYY: 1.09E+00 FCZ: 2.00E+00 6.71 KL/R-Y:156.49 RZZ: 2. Pro .872 — STAAD. Section 24 American Society of Mechanical Engineers – Nuclear Facility (ASME NF) Codes International Design Codes Manual — 873 . Pro .874 — STAAD. 2 Tension Allowable tensile stress on the Net section is calculated as (0. 24A.60*F ).3 Compression The allowable compressive stress for columns shall be as required by clause XVII-2213 of NF3000 1974.24A. ASME NF 3000 .1.1974 & 1977 requires the STAAD Nuclear Design Codes SELECT Code Pack.1 Slenderness As per clause XVII-2223 of NF-3000 1974. The default limit for TRUSS members in Tension is set at 300. the output file the reports the maximum utilization from all of the checks. the slenderness ratio KL/r of compression members shall not exceed 200.1 Design Process The design process follows the following design checks Each one of the checks are described in the following sections. and the NSF parameter can be utilized for that. Design of members per ASME NF 3000 .1974 & 1977 . Note: From design point of view. 24A. When a design is performed.1.Pro is capable of performing steel design based on the American Society of Mechanical Engineers Nuclear Facility Code. 24A. there are no major differences between NF-3000 1974 and NF-3000 1977 version of codes. ASME NF 3000 . International Design Codes Manual — 875 .1974 & 1977 Codes STAAD. and the slenderness ratio L/r of tension members.5*F ) on the Net area. 24A.1. preferably should not exceed 240 for main members and 300 for lateral bracing members and other secondary members. but not more than y (0. u The Net Area (An) shall be determined in accordance with the clause XVII-2283 of NF-3000 1974. The provisions for Pin-connected and Threaded tensile member are not implemented in STAAD. 6 − ( ) l 200r b. When (Kl/r) > Cc. For webs of rolled shapes.60·Fy 2.75·Fy The above clauses are applicable only when the width-thickness ratio of the element satisfies all the sub-sections of clause XVII-2224 of NF-3000 1974. 876 — STAAD. b . ASME NF 3000 . Fa = 0. a reduction factor.2 of NF-3000 1974. (a1) or Eq. e 1.3 1 − b / t f ≤ b ( ) Consequently. Q . Fa = 12π E 23(KL / r ) 2 2 3. is introduced. a reduced effective width. Detailed s values of Q for different shapes are given in the clause XVII-2225. a. (a 2) 1. s b.Pro . If the above-mentioned clauses are not satisfied.3 1 − b / t f ≤ b ( ) 2. For un-stiffened compression element. For the flanges of square and rectangular sections of uniform thickness: be = 253t f 50. Q . Gross Sections of Columns: 1. Fas = Fa Eq. a reduction factor. Member elements other than columns: 1. Fa = Fy 2 ( KL / r) 1 − 2 2 C c 5/3+ 3( KL / r) 8C c − ( KL / r) 3 8C c 3 Where: Cc = 2π E Fy 2 2. For other uniformly compressed elements: be = 253t f 44. Fa = 0.1974 & 1977 Codes a. equal to the effective area divided by the actual a area is introduced. When (Kl/r) > 120. when (Kl/r) < Cc. is introduced. For stiffened compression element.24A. For Plate Girder Stiffeners. On gross section of axially loaded compression members. y b. y d. The laterally unsupported length of the compression flange of members other than boxshaped members shall not exceed the value of 76b /√F nor 20000/(d/A )F .2/√F .33(F /F )] y a y except that it need not be less than 257/√F .Combining both these factors. Along Minor Axis: For doubly symmetrical members (I shaped) meeting the requirements of XVII-2214. y c. Along Major Axis: a. c. The depth-thickness ratio of the web shall not exceed d/t = (412/√F )[1 – 2. f y f y b. as given in XVII-2214 of NF-3000 1974 is: a.1(a) and (b) of NF-3000 1974.1.60*F b y b.2 and XVII-2214.4 Bending Stress Allowable bending stress for tension and compression for a structural member.5 of NF-3000 1974 are followed respectively. For box-type flexural members. For noncompact and slender elements. Width-thickness ratio of un-stiffened projecting elements of the compression flange shall not exceed 52. maximum tensile and compressive bending stress shall not exceed: International Design Codes Manual — 877 . tension and compression on extreme fibers of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection NF shall result in a maximum bending stress: F = 0. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√F . For Compact Sections. clause XVII-2214. allowable stress for axially loaded compression members containing stiffened or un-stiffened elements shall not exceed 2 ( KL / r) Q sQ a1 − 2 2C ′ c Fa = Fy 5/3+ 3( KL / r) 8C ′c − ( KL / r) 3 8C ′ c 3 Where: C ′c = 2π E Q sQ aF 2 y 24A.66*F b y If meeting the requirements of this member of: a. maximum bending stress is: F = 0. 00 / (a / h )2 . otherwise fa Fa + fbz Fbz + fby Fby ≤ 1.8 .85 for sidesway and 0.0 when fa/Fa > 0.6 .4Fy Where: Cv = Cv = 45. the gross section is taken as the total flange areas.1974 & 1977 Codes F = 0.1.60F y + fbz Fbz + fby Fby ≤ 1.24A. The value of the coefficient Cm is taken as 0.1.89)Cv ≤ 0. Members subjected to both axial tension and bending stress are proportioned to satisfy fa 0.Pro .8 k Fy k = 4.34 / (a / h )2 . if f /F exceeds unity.0 24A.2 of NF-3000 1974] is calculated as Fv = (Fy / 2. ASME NF 3000 . because this would result in a misleadingly liberal ratio.5 Combined Interaction Check Members subjected to both axial compression and bending stresses are proportioned to satisfy fa Fa C my fby + C mzfbz (1 − fa / F ′ex )Fbx + (1 − fa / F ′ey)Fby ≤ 1.34 + 4. when Cv > 0.15. XVII-2263. For shear on the flanges.4 for no side-sway.0 It should be noted that during code checking or member selection.00 + 5.0 and fa 0. when a/h < 1. when Cv < 0. 878 — STAAD.60F y + fbz Fbz + fby Fby ≤ 1.0 For actual shear on the web. but not less than 0.0. when a/h > 1. 000k F y (h / t ) 190 h/t 2 . the gross section is taken as the product of the total depth and the web thickness.0 k = 5. the a a program does not compute the second and third part of the formula.75*F b y 24A.4·(M1/M2).6 Shear Stress Allowable shear stress on the gross section [ref. 1 = Deflection check based on the principle that maximum deflection is of the cantilever type International Design Codes Manual — 879 . refer to Section 1.5. which means no allowable stresses of the member will be printed. HSS Pipe. Angle.3 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.5. Depending on the particular design requirements for an analysis. some or all of these parameter values may have to be changed to exactly model the physical structure. by default the KZ value (k value in local z-axis) of a member is set to 1. the TRACK value must be set to 1. If the allowable stresses are to be printed.1 of the Technical Reference Manual. while in the real structure it may be 1. the TRACK value of a member is set to 0. CAN 0 Used for Deflection Check only.0. as shown in the input instruction (Section 5).0. Member properties may also be specified using the User Table facility except for the General and Prismatic member.7 the STAAD Technical Reference Manual. In that case. 24A.1-ASME NF 3000 Design Parameters Parameter Name CODE Default Value Description - Must be specified as CODE NF3000 1974 or CODE NF3000 1977 Design Code to follow. The default parameter values have been selected such that they are frequently used numbers for conventional design. Tee.48. Double Channel section. Double Angle. HSS Tube. are listed in the following table. the specified steel section available in Steel Section Library of STAAD may be used namely – I-shaped section. Similarly. These parameter names. See section 5. For more information on these facilities.2 Member Property Specification For specification of member properties.0. Channel.24A. 0 = Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2. with their default values. Table 24A. the KZ value in the program can be changed to 1. For example. 0 = CB is calculated itself Any other user-defined value is accepted.85 for sidesway and calculated for no sidesway None (Mandatory for deflection check) Start Joint of member End Joint of member 45 inch Cm value in local y & z axes DFF "Deflection Length" / Maximum allowable local deflection DJ1 Joint No.0 inch FYLD 36 KSI FU 60 KSI KY 1.0 KZ 1.1974 & 1977 Codes Parameter Name CB Default Value Description 1. this is major axis. Ultimate tensile strength of steel in current units. Minimum allowable depth. Length to calculate slenderness ratio for buckling about local Y axis.24A. Used only with the MEMBER SELECTION command. this is minor axis. K value in local y-axis. ASME NF 3000 . denoting end point for calculation of "Deflection Length" Maximum allowable depth. CMY CMZ 0. Usually. denoting starting point for calculation of "Deflection Length" Joint No. DJ2 DMAX DMIN 0. K value in local z-axis. Usually.Pro . Used only with the MEMBER SELECTION command.0 LY Member Length 880 — STAAD. Yield strength of steel at temperature in current units.0 Bending coefficient dependent upon moment gradient 0. MAIN 0. Used in member selection. Will be used only if flexural compression on the bottom flange. See Section 5.48.0 = suppress slenderness check NSF 1.1 of the Technical Reference Manual for details. Minimum detail 1.0 Same as above except in z-axis (major). Maximum detail UNB Member Length Unsupported length of the bottom* flange for calculating allowable bending compressive stress. Intermediate detail level 2. Unsupported length of the top* flange for calculating allowable bending compressive stress. UNT Member Length International Design Codes Manual — 881 .0 Controls the levels of detail to which results are reported. Will be used only if flexural compression on the top flange.Parameter Name LZ Default Value Description Member Length 0.0 = check for slenderness 1. Spacing of stiffeners for plate girder design PROFILE None RATIO 1.0 Net Section Factor for tension member. Permissible ratio of the actual to allowable stresses. 0.0 STIFF Member length or depth whichever is greater 240 for main member 300 for “Truss” member TMAIN Slenderness limit under tension TRACK 0. 1974 & 1977 Codes 24A.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST W24X104 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED 882 — STAAD.4 Code Checking and Member Selection Both code checking and member selection options are available with the ASME NF-3000 1974 and ASME NF-3000 1977 codes. The corresponding input of STAAD input editor file is shown as below: STAAD SPACE START JOB INFORMATION ENGINEER DATE 18-JUN-08 END JOB INFORMATION UNIT INCHES KIP JOINT COORDINATES 1 0 0 0. 2 30 0 0. DEFINE MATERIAL START ISOTROPIC STEEL E 29000 POISSON 0.3 DENSITY 76.24A. The beam is assigned with W24X104 steel member and is designed in accordance with ASME NF3000 1974. MEMBER INCIDENCES 1 1 2.48. Refer to Section 5.2E-005 DAMP 0. 24A.8195 ALPHA 1.2 of the Technical Reference Manual for details the specification of the Code Checking command.48.5 of the Technical Reference Manual for general information on Code Checking. Refer to Section 2. ASME NF 3000 .5 Example A cantilever beam of length 30 inch is loaded at its free end with 5 kip compressive load and 5 kip lateral load.3 of the Technical Reference Manual for details the specification of the Member Selection command. Refer to Section 2.6 of the Technical Reference Manual for general information on Member Selection.Pro . Refer to Section 5. 07E+01 FCZ: 2.0 INCH (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST W24X104 (AISC SECTIONS) PASS NF-74-EQN-21 0.PRO CODE CHECKING .85 ALL CB 0 ALL TRACK 2 ALL CHECK CODE ALL FINISH The corresponding TRACK 2 output is as follows: STAAD.00 0.KIP INCH) | | AXIAL: 2.9 ALL KZ 0.70E+01 FTZ: 2.28 ALLOWABLE RATIO: 200.44E+01 | | ACTUAL STRESSES: (UNIT .63E-01 FBZ: 5.00E+00 SHEAR: 4.38E+01 FCY: 2.LOAD 1 JOINT LOAD 2 FX -5 FY -5 PERFORM ANALYSIS PRINT SUPPORT REACTION PRINT JOINT DISPLACEMENTS PRINT MEMBER FORCES PARAMETER 1 CODE NF3000 1974 FYLD 36 ALL FU 58 ALL KY 0.00 150.9 ALL NSF 0.00 | | ALLOWABLE STRESSES: (UNIT .KIP MEMBER TABLE v1.82E-01 FBY: 0.( ASME NF3000-74) ******************************************** ALL UNITS ARE .16E-01 | |----------------------------------------------------------------------------| International Design Codes Manual — 883 .00 |----------------------------------------------------------------------------| | SLENDERNESS CHECK: ACTUAL RATIO: 9.38E+01 FTY: 2.032 1 5.00 C 0.70E+01 | | SHEAR: 1.KIP INCH) | | AXIAL: 1. 1974 & 1977 Codes | SECTION PROPERTIES: (UNIT .00E+00 | | COMP&BEND 0.00E+00 1.00E+00 | | SHEAR-Y 0.00 CMY: 1.00E+00 | |----------------------------------------------------------------------------| 884 — STAAD.75 RZZ: 10.00 FU: 58.000 1 0.68 KL/R-Y: 9.000 1 5.00 NET SECTION FACTOR: 0.60 AYY: 12.28 UNL: 30.07 RYY: 2.63 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .008 1 5.00E+00 | | COMPRESSION 0.00E+00 | | SHEAR-Z 0.KIP INCH) | | KL/R-Z: 2.009 1 5.INCH) | | AXX: 30.24A.Pro .00 | | CB: 1.75 FYLD: 36. ASME NF 3000 .00E+00 | | TEN&BEND 0.029 1 5.85 | | | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | | CLAUSE RATIO LOAD FX VY VZ MZ MY | | TENSION 0.50E+02 0.69 SYY: 40.91 | | SZZ: 257.0 CMZ: 1.03 AZZ: 12.00E+00 1.50E+02 0.032 1 5. 75. (2) and (3). The provisions for Pin-connected and Threaded tensile member are not implemented in STAAD.8(c)(1) .1989 Code 24B.60*F ). When a design is performed.24B. ASME NF 3000 . Tension 3. shall be computed from the formula (ref. the slenderness ratio KL/r of compression members shall not exceed 200. International Design Codes Manual — 885 .8(c)(1)(d)(1). Compression 4. and the slenderness ratio L/r of tension members. Combined Interaction Check 6. Shear Stress Each one of the checks are described in the following sections. preferably should not exceed 240 for main members and 300 for lateral bracing members and other secondary members. u The Net Area (A ) shall be determined in accordance with NF-3322. n and the NSF parameter can be utilized for that. Bending Stress 5. The default limit for TRUSS members in Tension is set at 300. where the load is transmitted e by bolts through some but not all of the cross-sectional elements of the member. NF-3322.1 Slenderness As per NF-3322. The Effective Net Area (A ) of axially loaded tension members.(a). 24B. A =C *A e t n Unless otherwise specified.8(c)(1)(d)). the output file the reports the maximum utilization from all of the checks. but not more than y (0. the default value of the CT parameter is set as 0.1 Design Process The design process follows the following design checks. The value of CT parameter for other conditions is described at section NF-3322.5*F ) on the Effective Net area. 1.2(c).3 . (b) and (c).2 . Slenderness 2. 24B.2 Tension Allowable tensile stress on the Net section is calculated as (0. 1(c)(2).2(d). When (Kl/r) ≤ 120. When (Kl/r) > 120. including austenitic stainless steel. Fa = 12π E 23(KL / r ) 2 2 3. (a 2) 1. Fa = Fy 0. Fa = 0. Member elements other than columns: 1.75·Fy The above clauses are applicable only when the width-thickness ratio of the element satisfies all the sub-sections of NF-3322. except those fabricated from austenitic stainless steel shall be as required by NF-3322. 886 — STAAD. Gross Sections of Columns.47 − ( ( KL / r 444 ) ) 2.3 Compression The allowable compressive stress for columns.60·Fy 2. When (Kl/r) > Cc. a. For webs of rolled shapes. The allowable compressive stress for columns fabricated from austenitic stainless steel shall be as required by NF-3322.1(c)(1).24B.6 − ( ) l 200r b.40 − KL / r 600 c. Gross sections of columns fabricated from Austenitic Stainless steel: 1.1(c)(3). Fa = 0.Pro . shall be as required by NF-3322. For Plate Girder Stiffeners. The allowable compressive stress for member elements other than columns constructed by any material. Fa = Fy 2 ( KL / r) 1 − 2 2C c 5/3+ 3( KL / r) 8C c − ( KL / r) 3 8C c 3 Where: Cc = 2π E Fy 2 2. When (Kl/r) > 120.4 . Fas = Fa Eq. except those fabricated of austenitic stainless steel: 1. If the above-mentioned clauses are not satisfied. Fa = Fy 0. when (Kl/r) < Cc. On gross section of axially loaded compression members. (a1) or Eq. Width-thickness ratio of unstiffened projecting elements of the compression flange shall not exceed 65/√F . as given in NF3322. Q . allowable stress for axially loaded compression members containing stiffened or un-stiffened elements shall not exceed 2 ( KL / r) Q sQ a1 − 2 2C ′ c Fa = Fy 5/3+ 3( KL / r) 8C ′c − ( KL / r) 3 8C ′ c 3 Where: C ′c = 2π E Q sQ aF 2 y 24B. a reduction factor. Detailed s values of Q for different shapes are given in NF-3322. Along Major Axis: 1.3 1 − b / t f ≤ b ( ) 2.5 .3 1 − b / t f ≤ b ( ) Consequently. a reduction factor.2(e)(2)(d). e 1. equal to the effective area divided by the actual a area is introduced.66*F b y If meeting the requirements of this member of: a. is introduced. Q . For stiffened compression element. tension and compression on extreme fibres of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection NF shall result in a maximum bending stress: F = 0. y International Design Codes Manual — 887 . b . For Compact Sections. Combining both these factors.1(d) is: a.4 Bending Stress Allowable bending stress for tension and compression for a structural member.a. For un-stiffened compression element. is introduced. For the flanges of square and rectangular sections of uniform thickness: be = 253t f 50. a reduced effective width. s b. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√F . For other uniformly compressed elements: be = 253t f 44. y b.2(e)(2)(a) to NF-3322. except where b /2t exceeds 65/√F but is less than 95/√F .1(d)(5) and NF-3322.0.75*F b y 2.4·(M1/M2). For doubly symmetrical members (I shaped) meeting the requirements of NF3322. the a a program does not compute the second and third part of the formula. f y f y 2.1(d)(1)(a) and (b). NF-3322. if f /F exceeds unity.c.16 y a y a y d/t = 257/√F when f /F > 0.6 .74(f /F )] when f /F <=0.60*F b y b. For box-type flexural members. The depth-thickness ratio of the web shall not exceed d/t = (640/√F )[1 – 3.1(d)(3) are followed respectively. Members subjected to both axial tension and bending stress are proportioned to satisfy 888 — STAAD. maximum f f y y tensile and compressive bending stress shall not exceed: F = F [1. maximum bending stress is: F = 0.Pro .0 and fa 0. Along Minor Axis: 1.60F y + fbz Fbz + fby Fby ≤ 1.15.85 for sidesway and 0. The value of the coefficient Cm is taken as 0.0 It should be noted that during code checking or member selection.005(b /2t )√F ] b y f f y 24B.5 Combined Interaction Check Members subjected to both axial compression and bending stresses are proportioned to satisfy fa Fa + C mzfbz (1 − fa / F ′ex )Fbx + C my fby (1 − fa / F ′ey)Fby ≤ 1.1(d)(1)(a).0 when fa/Fa > 0. 3. maximum tensile and compressive bending stress shall not exceed: F = 0.4 for no side-sway.075 – 0. The laterally unsupported length of the compression flange of members other than box-shaped members shall not exceed the value of 76b /√F nor 20000/(d/A )F . otherwise fa Fa + fbz Fbz + fby Fby ≤ 1. For noncompact and slender elements.16 y a y d. but not less than 0. because this would result in a misleadingly liberal ratio.6 . For doubly symmetrical members (I shaped) meeting the requirements of NF3322. If the allowable stresses are to be printed.89)Cv ≤ 0. the TRACK value of a member is set to 0. refer to Section 1. Angle.7 . when Cv < 0. the KZ value in the program can be changed to 1. Double Angle. These parameter names.00 + 5. the gross section is taken as the total flange areas. The default parameter values have been selected such that they are frequently used numbers for conventional design. HSS Pipe. International Design Codes Manual — 889 . For shear on the flanges. For example. when Cv > 0.0 k = 5. the TRACK value must be set to 1.5.6 Shear Stress Allowable shear stress on the gross section [ref. In that case. are listed in the following table.6(e)(2)] is calculated as Fv = (Fy / 2. 24B. when a/h < 1. NF-3322. some or all of these parameter values may have to be changed to exactly model the physical structure. as shown in the input instruction (Section 5). Similarly. Double Channel section.60F y + fbz Fbz + fby Fby ≤ 1.0 For actual shear on the web. Channel.0.9 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.4Fy Where: Cv = Cv = 45.0.fa 0. Tee.34 / (a / h )2 . when a/h > 1. which means no allowable stresses of the member will be printed.0. Member properties may also be specified using the User Table facility except for the General and Prismatic member. the gross section is taken as the product of the total depth and the web thickness. 24B. with their default values.5. 000k F y (h / t ) 190 h/t 2 . HSS Tube. while in the real structure it may be 1.34 + 4.7 the STAAD Technical Reference Manual. by default the KZ value (k value in local z-axis) of a member is set to 1. For more information on these facilities.8 k Fy k = 4.0 24B.00 / (a / h )2 . the specified steel section available in Steel Section Library of STAAD may be used namely – I-shaped section. Depending on the particular design requirements for an analysis.8 .8 Member Property Specification For specification of member properties. Table 24B. DJ2 DMAX 890 — STAAD. See section 5. denoting starting point for calculation of "Deflection Length" Joint No. 1 = Deflection check based on the principle that maximum deflection is of the cantilever type CB 1.48. [Refer NF3322.Pro . in current units.0 Bending coefficient dependent upon moment gradient 0. denoting end point for calculation of "Deflection Length" Maximum allowable depth. Design Code to follow. 0 = Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2.8(c)(1)(d)] Cm value in local y & z axes CMY CMZ DFF 0.1 of the Technical Reference Manual. CAN 0 Used for Deflection Check only.75 Reduction Coefficient in computing effective net area of an axially loaded tension member. Used only with the MEMBER SELECTION command. CT 0.0 = CB is calculated itself Any other user-defined value is accepted.1-ASME NF 3000 Design Parameters Parameter Name CODE Default Value Description Must be specified as NF3000 1989.85 for sidesway and calculated for no sidesway None (Mandatory for deflection check) Start Joint of member End Joint of member 45 inch "Deflection Length" / Maximum allowable local deflection DJ1 Joint No. 0 = suppress slenderness check FYLD 36 KSI FU 60 KSI KY 1.0 = Normal Steel 1. See Section 5. this is minor axis. 0.0 LY Member Length LZ Member Length MAIN 0. Yield strength of steel at temperature in current units.0 NSF 1.48.0 = Austenitic Stainless Steel TMAIN 240 for main member 300 for “Truss” member Slenderness limit under tension International Design Codes Manual — 891 . Usually.Parameter Name DMIN Default Value Description 0. K value in local y-axis. Length to calculate slenderness ratio for buckling about local Y axis.0 Net Section Factor for tension member.0 STIFF Member length or depth whichever is greater 0. Same as above except in z-axis (major). Permissible ratio of the actual to allowable stresses.0 = check for slenderness 1. Used only with the MEMBER SELECTION command.0 STYPE 0. Spacing of stiffeners for plate girder design PROFILE None RATIO 1.0 KZ 1.1 of the Technical Reference Manual for details. Ultimate tensile strength of steel in current units.0 inch Minimum allowable depth. Usually. K value in local z-axis. Used in member selection. in current units. this is major axis. 2 of the Technical Reference Manual for details the specification of the Code Checking command. Will be used only if flexural compression on the top flange.6 Example A cantilever beam of length 100 inch is loaded at its free end with 5 kip compressive load and a uniformly distributed load of 1 kip/inch over the whole span.0 Controls the levels of detail to which results are reported. The beam is assigned with B571806 steel member and is designed in accordance with ASME NF3000 1989.24B. 24B.6 of the Technical Reference Manual for general information on Member Selection. UNT Member Length 24B. Unsupported length of the top* flange for calculating allowable bending compressive stress.3 of the Technical Reference Manual for details the specification of the Member Selection command.Pro .6 Example Parameter Name TRACK Default Value Description 0. Refer to Section 5. Refer to Section 5.10 Code Checking and Member Selection Both code checking and member selection options are available with the ASME NF-3000 1989 code. 18B. 0 = Minimum detail 1 = Intermediate detail level 2 = Maximum detail UNB Member Length Unsupported length of the bottom* flange for calculating allowable bending compressive stress.48. Refer to Section 2.48. Refer to Section 2. 18B.5 of the Technical Reference Manual for general information on Code Checking. Will be used only if flexural compression on the bottom flange. The corresponding input of STAAD input editor file is shown as below: STAAD SPACE START JOB INFORMATION ENGINEER DATE 18-JUN-08 END JOB INFORMATION 892 — STAAD. 0 0 100 PERFORM ANALYSIS PRINT SUPPORT REACTION PARAMETER 1 CODE NF3000 1989 STYPE 1 ALL FYLD 36 ALL KY 0. MEMBER INCIDENCES 1 1 2.( ASME NF3000-89) ******************************************** v1.75 ALL KZ 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST B571806 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED LOAD 1 JOINT LOAD 2 FX -5 MEMBER LOAD 1 UNI GY -1.8195 ALPHA 1.PRO CODE CHECKING .0 International Design Codes Manual — 893 . 2 360 0 0.2E-005 DAMP 0.75 ALL FU 58 ALL NSF 0. DEFINE MATERIAL START ISOTROPIC STEEL E 29000 POISSON 0.JOINT COORDINATES 1 0 0 0.9 ALL CB 0 ALL TRACK 2 ALL CHECK CODE ALL FINISH The corresponding TRACK 2 output is as follows: STAAD.3 DENSITY 76. 84 KL/R-Y: 75.99E+00 | |----------------------------------------------------------------------------| | SECTION PROPERTIES: (UNIT .08 AZZ: 15.80 RYY: 3.0 CMZ: 1.6 Example INCH (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST B571806 (AISC SECTIONS) PASS SHEAR Y 0.00E+00 | | COMP&BEND 0.75 FYLD: 36.00 AYY: 25.00E+00 5.0 | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | | CLAUSE RATIO LOAD FX VY VZ MZ MY | | TENSION 0.00E+00 | | SHEAR-Y 0.00E+03 0.00 0.00E+00 SHEAR: 3.00 C 0.000 1 5.00E+00 | | TEN&BEND 0. 18B.00E+00 5.00 RZZ: 22.00 |----------------------------------------------------------------------------| | SLENDERNESS CHECK: ACTUAL RATIO: 75.08 UNL: 360.009 1 5.00E+00 | | COMPRESSION 0.KIP INCH) | | AXIAL: 1.77 SYY: 67.00 5000.KIP INCH) | | AXIAL: 1.31E+01 | | SHEAR: 5.00 | | ALLOWABLE STRESSES: (UNIT .KIP INCH) | | KL/R-Z: 11.75 STEEL TYPE: 1.60 | | SZZ: 853.16E+01 FTY: 2.06E-01 FBZ: 5.86E+00 FBY: 0.770 1 5.00 | | CB: 1.00E+03 0.Pro .005 1 5.290 1 5.00 NET SECTION FACTOR: 0.INCH) | | AXX: 47.08E+01 FCY: 2.00E+02 | ALL UNITS ARE .13E+01 FCZ: 2.31E+01 FTZ: 2.90 | | CT: 0.00 CMY: 1.24B.KIP MEMBER TABLE 894 — STAAD.08 ALLOWABLE RATIO: 200.00 FU: 58.54 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .18E+00 | | ACTUAL STRESSES: (UNIT .770 1 1. 00E+00 | |----------------------------------------------------------------------------| International Design Codes Manual — 895 .000 1 0.| SHEAR-Z 0. Pro .896 — STAAD. The default limit for TRUSS members in Tension is set at 300. 24C. When a design is performed. The provisions for Pin-connected and Threaded tensile member are not implemented in STAAD. NF-3322.75.8(c)(1)(d)(1).24C. (2) and (3). Shear Stress Each one of the checks are described in the following sections. Combined Interaction Check 6.1 Slenderness As per NF-3322. A =C *A e t n Unless otherwise specified. The value of CT parameter for other conditions is described at section NF-3322.2004 Code 24C.8(c)(1)(d)). shall be computed from the formula (ref. (b) and (c). preferably should not exceed 240 for main members and 300 for lateral bracing members and other secondary members. 24C. International Design Codes Manual — 897 . where the load is transmitted e by bolts through some but not all of the cross-sectional elements of the member. the default value of the CT parameter is set as 0. 1. and the slenderness ratio L/r of tension members.1 Design Process The design process follows the following design checks. Slenderness 2. Compression 4. the output file the reports the maximum utilization from all of the checks.2 Tension Allowable tensile stress on the Net section is calculated as (0.2 . Tension 3. but not more than y (0.8(c)(1) . ASME NF 3000 . u The Net Area (A ) shall be determined in accordance with NF-3322.2(c).60*F ). n and the NSF parameter can be utilized for that. the slenderness ratio KL/r of compression members shall not exceed 200.5*F ) on the Effective Net area. Bending Stress 5.(a).3 . The Effective Net Area (A ) of axially loaded tension members. (a1) or Eq.47 − ( ( KL / r 444 ) ) 2. Fa = 12π E 23(KL / r ) 2 2 3.24C. Fa = 0.3 Compression The allowable compressive stress for columns. For webs of rolled shapes. a. When (Kl/r) ≤ 120. Fa = Fy 0. Gross Sections of Columns. Fa = Fy 2 ( KL / r) 1 − 2 2C c 5/3+ 3( KL / r) 8C c − ( KL / r) 3 8C c 3 Where: Cc = 2π E Fy 2 2.6 − ( ) l 200r b. The allowable compressive stress for columns fabricated from austenitic stainless steel shall be as required by NF-3322. shall be as required by NF-3322. Member elements other than columns: 1.1(c)(3). If the above-mentioned clauses are not satisfied.2004 Code 24C. Fas = Fa Eq.1(c)(2). When (Kl/r) > 120. (a 2) 1. except those fabricated from austenitic stainless steel shall be as required by NF-3322. including austenitic stainless steel. When (Kl/r) > Cc. Fa = 0. When (Kl/r) > 120. when (Kl/r) < Cc. Gross sections of columns fabricated from Austenitic Stainless steel: 1. Fa = Fy 0.4 . For Plate Girder Stiffeners. except those fabricated of austenitic stainless steel: 1. On gross section of axially loaded compression members.60·Fy 2.1(c)(1).75·Fy The above clauses are applicable only when the width-thickness ratio of the element satisfies all the sub-sections of NF-3322.Pro .40 − KL / r 600 c. The allowable compressive stress for member elements other than columns constructed by any material.2(d). 898 — STAAD. ASME NF 3000 . 293 − 0. as given in NF3322. a reduced effective width. a reduction factor. kc = 1. For other uniformly compressed elements: be = 253t f 44. For the flanges of square and rectangular sections of uniform thickness: be = 253t f 50.2(e)(2)(a) to NF-3322. e b. otherwise. Qs = 26. Combining both these factors. Q . Detailed s values of Q for different shapes are given in NF-3322.2(e)(2)(d).3 1 − b / t f ≤ b ( ) 2.4 Bending Stress Allowable bending stress for tension and compression for a structural member.a.1(d) is: a. For un-stiffened compression element. is introduced.46 when h/t > 70.0. 200kc F y (b / t ) 2 ( ) Fy / kc Where: kc = 4. 1.05 (h / t ) 0. When 95 / Fy / kc < b / t < 195 / Fy / kc . b . Q s = 1. s In the case for angles or plates projecting from compression members and for projecting elements of compression flanges of girder. For stiffened compression element. Q . a reduction factor.3 1 − b / t f ≤ b ( ) Consequently.5 . equal to the effective area divided by the actual a area is introduced. is introduced. Along Major Axis: International Design Codes Manual — 899 .00309 b / t When b / t > 195 / Fy / kc . allowable stress for axially loaded compression members containing stiffened or un-stiffened elements shall not exceed 2 ( KL / r) Q sQ a1 − 2 2C ′ c Fa = Fy 5/3+ 3( KL / r) 8C ′c − ( KL / r) 3 8C ′ c 3 Where: C ′c = 2π E Q sQ aF 2 y 24C. 60*F b y b. Width-thickness ratio of unstiffened projecting elements of the compression flange shall not exceed 65/√F .16 y a y d. The laterally unsupported length of the compression flange of members other than box-shaped members shall not exceed the value of 76b /√F nor 20000/(d/A )F .60F y + fbz Fbz + fby Fby ≤ 1.5 Combined Interaction Check Members subjected to both axial compression and bending stresses are proportioned to satisfy fa Fa + C mzfbz (1 − fa / F ′ex )Fbx + C my fby ( 1 − fa / F ′ey Fby ) ≤ 1. For doubly symmetrical members (I shaped) meeting the requirements of NF3322. except where b /2t exceeds 65/√F but is less than 95/√F .075 – 0.66*F b y If meeting the requirements of this member of: a. y b.2004 Code 1.Pro . NF-3322.1(d)(3) are followed respectively. The depth-thickness ratio of the web shall not exceed d/t = (640/√F )[1 – 3.74(f /F )] when f /F <=0.24C. f y f y 2. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√F . maximum f f y y tensile and compressive bending stress shall not exceed: F = F [1.1(d)(1)(a).1(d)(1)(a) and (b).005(b /2t )√F ] b y f f y 24C. For doubly symmetrical members (I shaped) meeting the requirements of NF3322. For noncompact and slender elements. maximum bending stress is: F = 0. tension and compression on extreme fibres of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection NF shall result in a maximum bending stress: F = 0.0 900 — STAAD. ASME NF 3000 . Along Minor Axis: 1. For Compact Sections. y c.6 . maximum tensile and compressive bending stress shall not exceed: F = 0.1(d)(5) and NF-3322.0 and fa 0. For box-type flexural members. 3.75*F b y 2.16 y a y a y d/t = 257/√F when f /F > 0. but not less than 0. refer to Section 1. NF-3322. the a a program does not compute the second and third part of the formula. For shear on the flanges.89)Cv ≤ 0.34 + 4. the gross section is taken as the total flange areas. HSS Tube.7 . when Cv < 0.0 It should be noted that during code checking or member selection. 24C. when a/h > 1.4Fy Where: Cv = Cv = 45. Double Angle. HSS Pipe. For more information on these facilities.8 .6 . if f /F exceeds unity.when fa/Fa > 0. when Cv > 0. Member properties may also be specified using the User Table facility except for the General and Prismatic member.4 for no side-sway. Double Channel section.0 k = 5. when a/h < 1.00 + 5.15. International Design Codes Manual — 901 . the specified steel section available in Steel Section Library of STAAD may be used namely – I-shaped section.8 k Fy k = 4.4·(M1/M2). the gross section is taken as the product of the total depth and the web thickness.8 Member Property Specification For specification of member properties.7 the STAAD Technical Reference Manual.34 / (a / h )2 . Channel.0.85 for sidesway and 0. 000k F y (h / t ) 190 h/t 2 . otherwise fa Fa + fbz Fbz + fby Fby ≤ 1. Angle.6 Shear Stress Allowable shear stress on the gross section [ref.00 / (a / h )2 .0 For actual shear on the web. Members subjected to both axial tension and bending stress are proportioned to satisfy fa 0. Tee. because this would result in a misleadingly liberal ratio.6(e)(2)] is calculated as Fv = (Fy / 2.0 24C.60F y + fbz Fbz + fby Fby ≤ 1. The value of the coefficient Cm is taken as 0. some or all of these parameter values may have to be changed to exactly model the physical structure. with their default values. Depending on the particular design requirements for an analysis.0 Bending coefficient dependent upon moment gradient 0. ASME NF 3000 .1 of the Technical Reference Manual.5.5. If the allowable stresses are to be printed. 1 = Deflection check based on the principle that maximum deflection is of the cantilever type CB 1. by default the KZ value (k value in local z-axis) of a member is set to 1. while in the real structure it may be 1. the TRACK value of a member is set to 0. 902 — STAAD. The default parameter values have been selected such that they are frequently used numbers for conventional design.Pro . See section 5.0 = CB is calculated itself Any other user-defined value is accepted. the KZ value in the program can be changed to 1. Design Code to follow. are listed in the following table. Table 24C.2004 Code 24C. CAN 0 Used for Deflection Check only. 0 = Deflection check based on the principle that maximum deflection occurs within the span between DJ1 and DJ2.0. For example.1-ASME NF 3000 1998 Design Parameters Parameter Name CODE Default Value Description - Must be specified as NF3000 1998. the TRACK value must be set to 1. These parameter names.0.48. In that case. which means no allowable stresses of the member will be printed. Similarly.0.9 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks.24C. as shown in the input instruction (Section 5). 8(c)(1)(d)] "Deflection Length" / Maximum allowable local deflection Joint No. Yield strength of steel at temperature in current units.85 for sidesway and calculated for no sidesway 0.Parameter Name CMY CMZ CT Default Value Description 0. this is major axis. in current units. denoting end point for calculation of "Deflection Length" Maximum allowable depth.75 Cm value in local y & z axes Reduction Coefficient in computing effective net area of an axially loaded tension member.0 inch FYLD 36 KSI FU 60 KSI KY 1. K value in local z-axis.0 LY Member Length International Design Codes Manual — 903 . in current units. Usually. DFF None (Mandatory for deflection check) Start Joint of member DJ1 DJ2 End Joint of member DMAX 45 inch DMIN 0. Used only with the MEMBER SELECTION command. Minimum allowable depth. this is minor axis. Used only with the MEMBER SELECTION command. Ultimate tensile strength of steel in current units. denoting starting point for calculation of "Deflection Length" Joint No. K value in local y-axis. Usually. Length to calculate slenderness ratio for buckling about local Y axis. [Refer NF3322.0 KZ 1. UNB Member Length 904 — STAAD.48.0 = Austenitic Stainless Steel TMAIN 240 for main member 300 for “Truss” member Slenderness limit under tension TRACK 0.0 Controls the levels of detail to which results are reported. 0 = Minimum detail 1 = Intermediate detail level 2 = Maximum detail RATIO 1.0 Net Section Factor for tension member.24C.2004 Code Parameter Name LZ Default Value Description Member Length Same as above except in z-axis (major).0 Permissible ratio of the actual to allowable stresses. Used in member selection. Unsupported length of the bottom* flange for calculating allowable bending compressive stress.Pro .0 = suppress slenderness check MAIN 0. See Section 5.0 = Normal Steel 1. ASME NF 3000 .1 of the Technical Reference Manual for details.0 NSF 1.0 = check for slenderness 1.0 STYPE 0. Will be used only if flexural compression on the bottom flange. 0. Spacing of stiffeners for plate girder design PROFILE None STIFF Member length or depth whichever is greater 0. 10 Code Checking and Member Selection Both code checking and member selection options are available with the ASME NF-3000 1998 code.5 of the Technical Reference Manual for general information on Code Checking. 18C.2 of the Technical Reference Manual for details the specification of the Code Checking command. Refer to Section 5.6 of the Technical Reference Manual for general information on Member Selection. 2 100 0 0. MEMBER INCIDENCES 1 1 2. 24C. The corresponding input of STAAD input editor file is shown as below: STAAD SPACE START JOB INFORMATION ENGINEER DATE 18-JUN-08 END JOB INFORMATION UNIT INCHES KIP JOINT COORDINATES 1 0 0 0. All values are entered in the current units.Parameter Name UNT Default Value Description Member Length Unsupported length of the top* flange for calculating allowable bending compressive stress. International Design Codes Manual — 905 . Refer to Section 2. 2. 24C.6 Example A cantilever beam of length 100 inch is loaded at its free end with 5 kip compressive load and a uniformly distributed load of 1 kip/inch over the whole span. The beam is assigned with B571806 steel member and is designed in accordance with ASME NF3000 1998. The parameters DMAX and DMIN are only used with the MEMBER SELECTION command.48. Notes 1.48. Will be used only if flexural compression on the top flange. Refer to Section 5. Refer to Section 2.3 of the Technical Reference Manual for details the specification of the Member Selection command. 6 Example DEFINE MATERIAL START ISOTROPIC STEEL E 29000 POISSON 0.9 ALL CT 0.PRO CODE CHECKING .( ASME NF3000-98) ******************************************** ALL UNITS ARE .8195 ALPHA 1.0 INCH (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 906 — STAAD.2E-005 DAMP 0.75 ALL KZ 0.85 ALL CB 0 ALL TRACK 2 ALL CHECK CODE ALL FINISH The corresponding TRACK 2 output is as follows: STAAD. 18C.0 0 100 PERFORM ANALYSIS PARAMETER 1 CODE NF3000 1998 STYPE 1 ALL FYLD 36 ALL KY 0.Pro .03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST B571806 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED LOAD 1 JOINT LOAD 2 FX -5 MEMBER LOAD 1 UNI GY -1.24C.KIP MEMBER TABLE v1.75 ALL FU 58 ALL NSF 0.3 DENSITY 76. 00E+00 5.22E+01 FCY: 2.85 STEEL TYPE: 1.99E+00 | |----------------------------------------------------------------------------| | SECTION PROPERTIES: (UNIT .00E+00 5.00 CMY: 1.005 1 5.00 FU: 58.00 | | CB: 1.00 C 0.0 | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | | CLAUSE RATIO LOAD FX VY VZ MZ MY | | TENSION 0.00E+00 SHEAR: 3.22E+01 FTY: 2.KIP INCH) | | KL/R-Z: 3.635 1 1.INCH) | | AXX: 47.00 NET SECTION FACTOR: 0.00 | | ALLOWABLE STRESSES: (UNIT .00E+02 | | SHEAR-Z 0.00E+00 | | SHEAR-Y 0.75 FYLD: 36.29 KL/R-Y: 20.272 1 5.85 UNL: 100.28E+00 | | ACTUAL STRESSES: (UNIT .(AISC SECTIONS) PASS SHEAR Y 0.90 | | CT: 0.00 AYY: 25.86E+00 FBY: 0.0 CMZ: 1.00E+03 0.00E+00 | | TEN&BEND 0.009 1 5.000 1 0.54 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .08 AZZ: 15.000 1 5.635 1 5.00 |----------------------------------------------------------------------------| | SLENDERNESS CHECK: ACTUAL RATIO: 20.80 RYY: 3.06E-01 FBZ: 5.77 SYY: 67.00E+00 | |----------------------------------------------------------------------------| 1 ST B571806 International Design Codes Manual — 907 .KIP INCH) | | AXIAL: 1.00E+03 0.60 | | SZZ: 853.00E+00 | | COMP&BEND 0.31E+01 FTZ: 2.00 RZZ: 22.20E+01 FCZ: 2.31E+01 | | SHEAR: 6.00 5000.KIP INCH) | | AXIAL: 1.00 0.00E+00 | | COMPRESSION 0.85 ALLOWABLE RATIO: 200. Pro .908 — STAAD. where the load is transmitted e by bolts through some but not all of the cross-sectional elements of the member. shall be computed from the formula (ref.1.8(c)(1)(d)).1 Design Process The design process follows the following design checks.8(c)(1) . and the slenderness ratio L/r of tension members.07. n and the NSF parameter can be utilized for that.2004 requires the STAAD Nuclear Design Codes SELECT Code Pack.1 Slenderness As per NF-3322.2 Tension Allowable tensile stress on the Net section is calculated as (0.(a). 24D. The Effective Net Area (A ) of axially loaded tension members. The Net Area (A ) shall be determined in accordance with NF-3322.60·F ). (b) and (c).30) or higher. Compression 4. The default limit for TRUSS members in Tension is set at 300. 24D.24D. A e = Ct · A n International Design Codes Manual — 909 . the output file the reports the maximum utilization from all of the checks. Tension 3. Combined Interaction Check 6. Slenderness 2.Pro is capable of performing steel design based on the American Society of Mechanical Engineers Nuclear Facility Code.2004.5·F ) y u on the Effective Net area. NF-3322. ASME NF 3000 . Bending Stress 5. Shear Stress Each one of the checks is described in the following sections. 24D. the slenderness ratio KL/r of compression members shall not exceed 200. Design of members per ASME NF 3000 . When a design is performed. Note: This feature requires STAAD.Pro V8i (SELECTseries 2) NRC (build 20.1.2(c).2004 Code STAAD. ASME NF 3000 . 1. but not more than (0.07. preferably should not exceed 240 for main members and 300 for lateral bracing members and other secondary members. Fa = 12·π2 E/[23(kL/r)2 ] (Eq. ASME NF 3000 .A1) or (Eq.1. the default value of the CT parameter is set as 0.40 .1(c)(3).(Kl/r)/600] C. The allowable compressive stress for columns fabricated from austenitic stainless steel shall be as required by NF-3322.[l/(200r)]} B. Gross Sections of Columns. A2)]/{1.24D. Fa = Fy [0. shall be as required by NF-3322. When (Kl/r) > Cc. 24D. except those fabricated from austenitic stainless steel shall be as required by NF-3322.Pro . (2) and (3). A. When (Kl/r) > 120. A1) Where: Cc = [(2·π2 E)/Fy ]1/2 2. Fas = Fa[(Eq. For Plate Girder Stiffeners.[(Kl/r)3 /(8·Cc3 )]} (Eq. The provisions for Pin-connected and Threaded tensile member are not implemented in STAAD.3 Compression The allowable compressive stress for columns. Gross sections of columns fabricated from Austenitic Stainless steel: 1.8(c)(1)(d)(1). when (Kl/r) ≤ Cc. Member elements other than columns: 1.2004 Code Unless otherwise specified.(Kl/r)2 /(2·Cc2 )]Fy / {5/3 + [3(Kl/r)/(8·Cc)] .(Kl/r)/444] 2.60·Fy 910 — STAAD. The value of CT parameter for other conditions is described at section NF-3322.1(c)(2).47 . When (Kl/r) ≤ 120. Fa = [1 .75. The allowable compressive stress for member elements other than columns constructed by any material. Fa = Fy [0. Fa = 0. including austenitic stainless steel.1(c)(1). except those fabricated of austenitic stainless steel: 1. On gross section of axially loaded compression members.6 . A2) 3. When (Kl/r) > 120. 75·Fy The above clauses are applicable only when the width-thickness ratio of the element satisfies all the sub-sections of NF-3322. allowable stress for axially loaded compression members containing stiffened or unstiffened elements shall not exceed Fa = QsQa[1 .44. A reduced effective width b is introduced. If the above-mentioned clauses are not satisfied.200·kc/[Fy (b/t)2 )] Where: kc = 4. a reduction factor Q is introduced and is equal to the effective area a divided by the actual area.3/[(b/t)√(f)]} ≤ b 2. otherwise kc = 1.3/[(b/t)√(f)]} ≤ b Consequently. a.2(e)(2)(a) to NF-3322..05/[(h/t)0.00309·(b/t)·(Fy /kc)1/2 When b/t > 195/(Fy /kc)1/2 . When 95/(Fy /kc)1/2 < b/t < 195/(Fy /kc)1/2 .0.50.1(d) is: International Design Codes Manual — 911 . Qs = 1.2. Qs = 26. In the case for angles or plates projecting from compression members and for projecting elements of compression flanges of girder. A reduction factor Q is introduced. as given in NF3322.1. Fa = 0. For other uniformly compressed elements: be = 253·t/√(f){1 .0. For webs of rolled shapes. Combining both these factors. b. e 1.2(e)(2)(d). For stiffened compression element.4 Bending Stress Allowable bending stress for tension and compression for a structural member. For the flanges of square and rectangular sections of uniform thickness: be = 253·t/√(f){1 .(Kl/r)2 /(2·Cc2 )]Fy / {5/3 + [3(Kl/r)/(8·Cc)] .2(d). For un-stiffened compression element.46 ] if h/t > 70.293 .[(Kl/r)3 /(8·Cc3 )]} Where: C'c = [(2·π2 E)/(QsQaFy )]1/2 24D. Detailed values of Q for different shapes are given s s in NF-3322. 1(d)(5) and NF-3322.1(d)(1)(a) and (b).1.66·Fy If meeting the requirements of this member of: a.1(d)(1)(a). ASME NF 3000 . c. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√Fy . maximum tensile and compressive bending stress shall not exceed: Fb = 0. maximum bending stress is: Fb = 0. The depth-thickness ratio of the web shall not exceed d/t = (640/√Fy )[1 – 3.16 d/t = 257/√Fy when fa/Fy > 0. For doubly symmetrical members (I shaped) meeting the requirements of NF3322. NF-3322. For doubly symmetrical members (I shaped) meeting the requirements of NF3322.75·Fy 2. Along Minor Axis: 1. For box-type flexural members. b. tension and compression on extreme fibres of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection NF shall result in a maximum bending stress: Fb = 0.2004 Code A.24D.1(d)(3) are followed respectively. For Compact Sections.5 Combined Interaction Check Members subjected to both axial compression and bending stresses are proportioned to satisfy fa Fa C my fby + C mzfbz (1 − fa / F ′ex )Fbx + (1 − fa / F ′ey)Fby ≤ 1.005(bf/2tf)√Fy ] 24D. maximum tensile and compressive bending stress shall not exceed: Fb = Fy [1.75·Fy B.16 d.0 and 912 — STAAD. except where bf/2tf > 65/√Fy but is less than 95/√Fy . The laterally unsupported length of the compression flange of members other than box-shaped members shall not exceed the value of 76bf/√Fy nor 20000/(d/Af)Fy .Pro .74(fa/Fy )] when fa/Fy ≤ 0. Width-thickness ratio of unstiffened projecting elements of the compression flange shall not exceed 65/√Fy . 2. Along Major Axis: 1.075 – 0. 3. For noncompact and slender elements. 0 For actual shear on the web. otherwise fa Fa + fbz Fbz + fby Fby ≤ 1. 24D. Double Angle. HSS Pipe. the specified steel section available in Steel Section Library of STAAD may be used namely – I-shaped section. because this would result in a misleadingly liberal ratio.0 It should be noted that during code checking or member selection. The value of the coefficient Cm is taken as 0.0 24D.00 / (a / h )2 .fa 0.00 + 5. Angle. Members subjected to both axial tension and bending stress are proportioned to satisfy fa 0.34 + 4.89)Cv ≤ 0. the gross section is taken as the product of the total depth and the web thickness.6 .1.0 k = 5.0 when fa/Fa > 0.2 Member Property Specification For specification of member properties. For shear on the flanges. HSS Tube.4Fy Where: Cv = Cv = 45. Channel. the gross section is taken as the total flange areas.6(e)(2)] is calculated as Fv = (Fy / 2. but not less than 0. the a a program does not compute the second and third part of the formula. when a/h > 1. International Design Codes Manual — 913 .34 / (a / h )2 .7 the STAAD Technical Reference Manual.0.4 for no side-sway. 000k F y (h / t ) 190 h/t 2 .8 .15.8 k Fy k = 4. when a/h < 1. For more information on these facilities. if f /F exceeds unity. Member properties may also be specified using the User Table facility except for the General and Prismatic member. Double Channel section. refer to Section 1. NF-3322.60F y + fbz Fbz + fby Fby ≤ 1.60F y + fbz Fbz + fby Fby ≤ 1.85 for sidesway and 0. Tee. when Cv > 0. when Cv < 0.6 Shear Stress Allowable shear stress on the gross section [ref.4·(M1/M2). 2004 Code 24D. CB 1. The default parameter values have been selected such that they are frequently used numbers for conventional design. with their default values.0 Bending coefficient dependent upon moment gradient 0.0.85 for sidesway and calculated for no sidesway 0.1 of the Technical Reference Manual. Table 24D. These parameter names.3 Design Parameters The program contains a large number of parameter names which are required to perform design and code checks. See section 5. by default the KZ value (k value in local z-axis) of a member is set to 1. Depending on the particular design requirements for an analysis. as shown in the input instruction (Section 5).5. CMY CMZ 0.24D. while in the real structure it may be 1.0.8(c)(1)(d)] 914 — STAAD. ASME NF 3000 . some or all of these parameter values may have to be changed to exactly model the physical structure.48. which means no allowable stresses of the member will be printed. [Refer NF-3322.0. the TRACK value of a member is set to 0.1-ASME NF 3000 2004 Design Parameters Parameter Name CODE Default Value Description Must be specified as NF3000 2004 Specified design code is followed for code checking purpose. the TRACK value must be set to 1.75 Cm value in local y & z axes CT Reduction Coefficient in computing effective net area of an axially loaded tension member. For example.0 = CB is calculated itself Any other user-defined value is accepted. Similarly.5. Design Code to follow. In that case. If the allowable stresses are to be printed.Pro . are listed in the following table. the KZ value in the program can be changed to 1. 0 LZ MAIN 0. Ultimate tensile strength of steel in current units. K value in local z-axis. this is major axis. Same as above except in z-axis (major).0 1.0 KZ 1.0 inch 36 KSI Joint No. Usually. K value in local y-axis.0 = suppress slenderness check NSF RATIO 1. denoting end point for calculation of "Deflection Length" Maximum allowable depth Minimum allowable depth Yield strength of steel at temperature in current units. this is minor axis. Permissible ratio of the actual to allowable stresses. Usually.0 Net Section Factor for tension member. DMAX DMIN FYLD FU 60 KSI KY 1.0 LY Member Length Member Length 0. Length to calculate slenderness ratio for buckling about local Y axis.0 = check for slenderness 1. STIFF Member Spacing of stiffeners for plate girder design length or depth whichever is greater International Design Codes Manual — 915 . denoting starting point for calculation of "Deflection Length" DJ2 Joint No.Parameter Name DFF Default Value None (Mandatory for deflection check) Description "Deflection Length" / Maximum allowable local deflection DJ1 Start Joint of the member End Joint of the member 45 inch 0. The parameters DMAX and DMIN are only used with the MEMBER SELECTION command.Pro . ASME NF 3000 .0 Description 0. Minimum detail 1. Will be used only if flexural compression on the top flange. Refer to Section 5. Intermediate detail level 2.2 of the Technical Reference Manual for details the specification of the Code Checking command. 24D. Refer to Section 2.3 of the Technical Reference Manual for details the specification of the Member Selection command. Unsupported length of the top* flange for calculating allowable bending compressive stress. The beam is assigned with B571806 steel member and is designed in accordance with ASME NF3000 2004. Refer to Section 5. Will be used only if flexural compression on the bottom flange.4 Code Checking and Member Selection Both code checking and member selection options are available with the ASME NF-3000 2004 code. UNT Member Length Notes 1. Maximum detail UNB Member Length Unsupported length of the bottom* flange for calculating allowable bending compressive stress. The corresponding input of STAAD input editor file is shown as below: 916 — STAAD.2004 Code Parameter Name STYPE Default Value 0.0 = Normal Steel 1. 24D.0 = Austenitic Stainless Steel TRACK 0.5 of the Technical Reference Manual for general information on Code Checking. All values are entered in the current units.48. 0.6 of the Technical Reference Manual for general information on Member Selection. Refer to Section 2.48.0 Controls the levels of detail to which results are reported. 2.5 Example A cantilever beam of length 100 inch is loaded at its free end with 5 kip compressive load and a uniformly distributed load of 1 kip/inch over the whole span.24D. 85 ALL CB 0 ALL TRACK 2 ALL International Design Codes Manual — 917 . MEMBER INCIDENCES 1 1 2.3 DENSITY 76. 2 100 0 0.75 ALL FU 58 ALL NSF 0.75 ALL KZ 0.9 ALL CT 0.2E-005 DAMP 0. DEFINE MATERIAL START ISOTROPIC STEEL E 29000 POISSON 0.0 0 100 PERFORM ANALYSIS PARAMETER 1 CODE NF3000 2004 STYPE 1 ALL FYLD 36 ALL KY 0.03 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 1 TABLE ST B571806 CONSTANTS MATERIAL STEEL ALL SUPPORTS 1 FIXED LOAD 1 JOINT LOAD 2 FX -5 MEMBER LOAD 1 UNI GY -1.STAAD SPACE START JOB INFORMATION ENGINEER DATE 18-JUN-08 END JOB INFORMATION UNIT INCHES KIP JOINT COORDINATES 1 0 0 0.8195 ALPHA 1. 1(b) 0.00 RZZ: 22.24D.22E+01 FCY: 2.99E+00 | |----------------------------------------------------------------------------| | SECTION PROPERTIES: (UNIT .85 ALLOWABLE RATIO: 200.00E+00 SHEAR: 3.85 UNL: 100.Pro .0 CMZ: 1.80 RYY: 3.KIP INCH) | | KL/R-Z: 3.00 5000.86E+00 FBY: 0.00 |----------------------------------------------------------------------------| | SLENDERNESS CHECK: ACTUAL RATIO: 20.00 AYY: 25.77 SYY: 67.22E+01 FTY: 2.90 | | CT: 0.PRO CODE CHECKING .00 C 0.28E+00 | | ACTUAL STRESSES: (UNIT .31E+01 | | SHEAR: 6.60 | | SZZ: 853.29 KL/R-Y: 20.20E+01 FCZ: 2. ASME NF 3000 .54 | |----------------------------------------------------------------------------| | PARAMETER: (UNIT .KIP INCH) | | AXIAL: 1.08 AZZ: 15.31E+01 FTZ: 2.00 CMY: 1.06E-01 FBZ: 5.00 0.75 FYLD: 36.0 INCH (UNLESS OTHERWISE NOTED) RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST B571806 (AISC SECTIONS) PASS NF-3322.00 | | ALLOWABLE STRESSES: (UNIT .KIP INCH) | | AXIAL: 1.00 | | CB: 1.( ASME NF3000-04) ******************************************** ALL UNITS ARE .85 STEEL TYPE: 1.KIP MEMBER TABLE v1.00 FU: 58.INCH) | | AXX: 47.00 NET SECTION FACTOR: 0.635 1 5.0 | |----------------------------------------------------------------------------| | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH) | | CLAUSE RATIO LOAD FX VY VZ MZ MY | 918 — STAAD.2004 Code CHECK CODE ALL FINISH The corresponding TRACK 2 output is as follows: STAAD. 00E+02 | | SHEAR-Z 0.00E+00 | | COMP&BEND 0.272 1 5.00E+03 0.00E+00 | | COMPRESSION 0.000 1 5.00E+00 | |----------------------------------------------------------------------------| International Design Codes Manual — 919 .00E+00 5.00E+00 | | SHEAR-Y 0.00E+03 0.00E+00 5.009 1 5.| TENSION 0.005 1 5.000 1 0.00E+00 | | TEN&BEND 0.635 1 1. 920 — STAAD.Pro . bentley.com/kbase/ — Search the Bentley Systems knowledge base for solutions for common problems.com/forums/5932/ShowForum. You do not need to be a Bentley SELECT member to use Service Ticket Manager.com/serviceticketmanager — Create and track a service ticket using Bentley Systems' online site for reporting problems or suggesting new features. FAQs and TechNotes — http://communities.com/Products/Structural/Structural_Analysis___ Design/w/Structural_Analysis_and_Design__Wiki/structural-product-technotesand-faqs. however you do need to register as a user. Ask Your Peers — http://communities.bentley.aspx — Post questions in the Be Community forums to receive help and advice from fellow users.bentley. l l l International Design Codes Manual — 921 .aspx — Here you can find detailed resolutions and answers to the most common questions posted to us by you.bentley. Knowledge Base — http://appsnet.Section 24 Technical Support Section 24 Technical Support These resources are provided to help you answer support questions: l Service Ticket Manager — http://www. 922 — STAAD.Pro . 54 739 121 195 505 AS 4100 . AIJ 2005 80 795 793 Codes B 49 See National Annex. 244 International Design Codes Manual — 923 . CAN/CSA-086-01 Canadian Codes 119 Canadian Wood Design Manual 183 Cold Formed Steel IS801 Concrete Design AIJ 1991 AS 3600 B4 BBK 94 BS8007 BS8110 CP65 CSA A23. AIJ 2002 See Steel Design. AIJ 1991 See Steel Design.13 Axially Loaded Members Design See Steel Design. ASCE 10-97 813 873 9 808 808 808 224. BS 5950-5 283 79 See Steel Design.Index British A AIJ 1991 AIJ 2002 AIJ 2005 AISC Alclad Aluminum Design See Concrete Design. AS 4100 ASCE 10-97 ASCE Manuals ASME NF Codes Australian Codes Axial Compression Axial Tension Clause 3.2001 14 835 21 See Concrete Design.3 Cyprus 543 11 371 787 97 51.1998 See Steel Design. BS8110 C National Annex British Codes BS 5950-5 BS EN 1993-1-1 BS4360 BS5400 BS5950 BS8110 American Transmission Tower Code813 Analysis PDelta ANSI/AISC N690 Codes AS 1170 AS 3600 . British 67 See Steel Design. AS 3600 CAN/CSA-086-01 See Wood Design. 244 224. 242. 240. BS5400 See Steel Design. 242. BS5950 See Concrete Design. 240. CSA CAN/CSA-S1601 Eurocode Steel Design 221. 238. IS 800 2007 See Concrete Design. 224. 256 798 F European Codes Extrusions Finnish National Annex French Codes Concrete Design National Annex 379 381 See National Annex. 240.3 399 777 215 441 419 685 585 747 122. 256 Steel Design Axially Loaded Members 224. 240. 224 224. 242. 256 213. 240. 242. 240. CSA A23. 242. 125 See Concrete Design. Finnish CSA CAN/CSA-S16-01 D DD ENV DD ENV 1993 Design 221 221. IS801 J Japanese Codes Concrete Design 541 See Concrete Design. 238. IS13920 See Concrete Design. 244. 242.Pro . 244. 244. 256 224. 215. AIJ 1991 79 See National Annex. 240. French 387 G GB 1591 I IS 800 2007 IS13920 See Steel Design. 244 Design Rules Structural Steelwork Dutch National Annex See National Annex. IS456 See Steel Design.3 See Steel Design. Dutch 387 387 IS456 IS801 E EC5 EN 1993 Equivalent slenderness 349 237 74 924 — STAAD. 244.Index: CSA – Japanese DIN 1045 EHE Eurocode EC2 IS13920 IS456 NS 3473 NTC 1987 SABS-0100-1 CSA CSA A23. 242. 240. 242. 240.23-81 SS EN 1993-1-1 Steel Design ANSI/AISC N690-1994 AS 4100 ASCE 10-97 B7 BS 5950-5 BS5400 BS5950 National Application Documents 215. 238.23-81 284 224. 271 284 283 283 284 284 284 281 284 284 AIJ 2002 AIJ 2005 SABS-0100-1 S See Steel Design. AIJ 2005 M Polish National Annex See National Annex. Polish Modulus of Elasticity N N690 Codes National Annex Belgian British Dutch Finnish French Norwegian output Polish Singaporean 27 S136-94 835 237. 222 NBN EN 1993-1-1 NEN-EN 1993 NF EN 1993-1-1 Norwegian National Annex See National Annex. SABS-0100-1 284 See Steel Design. S136-94 See Steel Design. SNiP 2. 244. 224. NTC 1987 P PN EN 1993-1-1 284 284 283 284 BSK 99 CSA CAN/CSA-S16-01 DIN 18800 DS412 Eurocode French Code IS 800 2007 NS-EN 1993 NTC 1987 International Design Codes Manual — 925 . Norwegian 284 See Concrete Design. SAB0162-1 1993 See Concrete Design. 813 565 551 837 19 807 375 101 93 67 783 129 407 203 221. 244. 242. 256.Steel Design See Steel Design. 256 387 513 SAB0162-1 1993 SFS EN 1993-1-1 SNiP 2. 99. 154. 743 68 565 387 387 781 CAN/CSA-086-01 Y Young's Modulus 173 See Modulus of Elasticity 349 See National Annex. 770 80 53.Pro . British V Verification Problem AIJ 2005 ASME NF 3000 1974 ASME NF 3000 1989 559 882 892 926 — STAAD. 151. 364 765. 768.23-81 Steel Design per IS 800 Steel Section Library British Japanese Structural Steelwork Design Rules Swedish Codes T Timber Design EC5 U UK National Annex 483 505 775 209 663 609 597 165 753 719 465 ASME NF 3000 1998 ASME NF 3000 2004 British Cold Formed Steel CSA CSA Wood EC5 SAB0162-1 W Weld Type Wood and Armer Moments Wood Design 905 916 112 148.Index: Steel Design per IS 800 – Young's Modulus IS 802 IS801 NBE-MV103-1972 NEN 6770 NORSOK N-004 NS 3472 / NPD NTC 1987 S136-94 SAB0162-1 1993 SNiP 2. 156 183 360. 199. bentley. Incorporated 685 Stockton Drive. Exton.com International Design Codes Manual — 927 .Bentley Systems. PA 19341 USA +1 (800) 236-8539 www.