CIRCLY 5.0 User Manual

CIRCLY 5 User Manual MINCAD Systems Pty. Ltd. P.O. Box 2114, Richmond South, Vic., 3121 Australia Tel.:(03) 9427 1085 Intl. +613 9427 1085 Fax:(03) 9428 1197 Intl. +613 9428 1197 Email: [email protected] Web: http://www.mincad.com.au January 2004 © MINCAD Systems Pty. Ltd. CIRCLY 5 User Manual MINCAD Systems Pty. Ltd. P.O. Box 2114, Richmond South, Vic., 3121 Australia Tel.:(03) 9427 1085 Intl. +613 9427 1085 Fax:(03) 9428 1197 Intl. +613 9428 1197 Email: [email protected] Web: http://www.mincad.com.au January 2004 © MINCAD Systems Pty. Ltd. Contents Summary CIRCLY End User Licence Agreement Introduction Overview ....................................................................... ................................................................7 Special Features for Pavement Engineering ...................................... ...........................................8 Cumulative Damage Concept....................................................... .......................................8 Material performance ........................................................... ................................................9 Traffic and Loading ............................................................ ................................................10 Wheel Loadings ................................................................. ................................................10 Automatic thickness design ..................................................... ..........................................10 ESA Multipliers................................................................. ..................................................10 Methods for handling Damage Pulses.............................................. .................................10 Overview of User Interface Introduction.................................................................... ..............................................................11 Creating, Opening and Saving Files ............................................. ...............................................12 Creating and Editing Input Data................................................. ..................................................12 Database Approach .............................................................. .............................................13 Running CIRCLY32 Analysis and Plotting Results.................................. ....................................13 Run Analysis ................................................................... ...................................................13 Plot Results.................................................................... ....................................................13 Options ........................................................................ ................................................................13 What's New in Version 5.0 Overview ....................................................................... ..............................................................15 Support of Austroads 2004 Pavement Design Guide ................................ ..................................15 New "built-in" Graphics Engine ................................................. ...................................................16 Cost Calculation ............................................................... ............................................................18 Automatic Parametric Analysis .................................................. ..................................................19 How to Start Using CIRCLY Getting Started: Assembling and Running a Job .................................. .......................................21 Global Coordinate System ....................................................... ....................................................28 Alternative Calculation Options Overview ....................................................................... ..............................................................31 Damage Calculation Details...................................................... ...................................................31 Thickness Design Capability..................................................... ...................................................33 Calculate Selected Results at User-defined z-Values ............................ .....................................34 Contents How to Use Advanced Features Cost Calculation ............................................................... ............................................................37 Calculation of Total Cost....................................................... .............................................37 Material Costs ................................................................. ...................................................38 Automatic Parametric Analysis .................................................. ..................................................39 Example Cost Optimization ........................................................ ...............................................41 How to Modify the Databases Introduction.................................................................... ..............................................................47 Units........................................................................... .......................................................47 Sign Convention................................................................. ................................................48 Overview of Database Approach .................................................. .....................................49 The "Layered System" and "Materials" Databases.................................. ....................................50 Overview of Layered System and Material Properties ............................. .........................50 Cross-anisotropy and isotropy in road pavement materials ....................... .......................51 Creating a new Layered System................................................... .....................................52 Defining the Layer properties................................................... ..........................................53 Duplicating a Layered System ................................................... ........................................54 Adding a new Elastic Material................................................... .........................................55 Adding a new Performance Criterion.............................................. ...................................57 Adding a new Material Type ..................................................... .........................................59 The "Loads" and "Traffic Spectrum" Databases ................................... .......................................60 Introduction ................................................................... .....................................................60 Adding a new Traffic Spectrum................................................... .......................................60 Duplicating a Traffic Spectrum.................................................. .........................................61 Coordinate System for Loads .................................................... ......... ..................................................................................................... ......................................e.................80 Changes to Materials ........................................................................................................... a Vehicle or Axle Group).................................................................................................................82 References.................75 How to Use New Austroads 2004 Features Modelling the Standard Axle......... .................................... ...........................65 Important Note about Axle Locations.............63 Defining Load Locations (i........................................................ ............ ...................................74 Project Reliability ..............e.......................75 Material Properties................69 Appendices Overview of Austroads 2004 Features Model of Standard Axle.........62 Adding a new Load Group (i................................................................ ....83 .............81 Austroads 2004 Examples.. ................ ....... .............................. ........... .......................................................................................................................................67 Coordinates for Results.... ...................................................................................................................................................... Wheel positions)..........79 How to Use Project Reliability........................................................................65 Important Note about Damage Pulses....................................................................................................... CIRCLY has many other powerful features... The first mainframe version of CIRCLY was released in 19 77 and the current Windows version is Version 5. 2004) that is widely used in Australia a nd New Zealand. torsional. non-uniform surface contact stress distributions.. Othe r geotechnical applications... CI RCLY uses state-of-the-art material properties and performance models and is continuo usly being developed and extended. . horizontal. allows for fine-tunin g of layer thicknesses to minimize construction and maintenance costs. can also b e analysed using CIRCLY. It is an integral component of the Aus troads Pavement Design Guide (Austroads. including selection of: . . including vertical. The system calculates the cumulative damage induced by a traffic spectr um consisting of any combination of user-specified vehicle types and load configura tions. cross-anisotropic and isotropic material properties. 1992. Combining this with a Cost Analysis feature. such as foundation engineering and settlement analysis.Summary CIRCLY software is for the mechanistic analysis and design of road pavements. . . etc. As well as using the usual 'equivalent' single wheel and axle load approximations. and . fully continuous (rough) or fully frictionless (smooth) layer interfaces. automatic sub-layering of unbound granular materials. while simultaneously designing the thickness of another layer. A Parametric Analysis feature can loop through a range of thicknesses for one or two layers.. optionally the contribution of each vehicle/load configuration can be explicitly analysed. This feature will optimise up to three layers. a comprehensive range of load types. and if the breach relates to services the supplying of the s ervices again. Customer warrants that it has not relied on any representation made by Mincad Sy stems or upon any descriptions or illustrations or specifications contained in any docume nt including any catalogues or publicity material produced by Mincad Systems.Exclusions and Limitation of Liability 21. 21. at the option of Mincad Sy stems. statutory or otherwise.CIRCLY End User Licence Agreement CIRCLY (c) Mincad Systems Pty Ltd ABN 27 006 782 832. the repair of such goods. the liability of Mincad Systems for any breach of such term shall be limited. Where legislation implies in this Agreement a ny condition or warranty and that legislation avoids or prohibits provisions in a c ontract excluding or modifying the application of or the exercise of or liability under such term. or the payment of the cost of having the goods repaired. photocopied. which may be suffered or incurred or which may arise directly or indirectly in respect to the supply of goods or services pursuant to this Agreement or the act. 21. such term shall be deemed to be included in this Agreement. which appears under the CIRCLY "About" dialogue box which provides (in part). All rights Reserved. the payment o f the cost of replacing the goods or of acquiring equivalent goods. or the payment of the cost of having the services supplied again. translated or reduced to any electronic medium or machine readable form. to any one or more of the following: if the breach related to goods: the replacemen t of the goods or the supply of equivalent goods. without the prior written consent of Mincad Systems.2 To the maximum extent permitted by law and subject only subject only to the warranties and remedies set out in Clause 12 and Sub-clause 21. relating in any way to the subject matter of this Agreem ent or to this Agreement generally. However. in whol e or part. tortious or otherwise) to Customer in respect of any loss or damage (including.1 To the maximum extent permitted by law all warranties whether express. impl ied. failure or omission of Mincad Systems. . without limitation. consequential loss or damage) howsoever caused. This documentation is licensed and sold pursuant to the terms and conditions of the CIRCLY End User Licence Agreement. reproduce d. Mincad Systems shall not be under any liability (contractual.1. are excluded. Copyright This manual is copyright and may not be copied. 22. (b) CIRCLY is supplied with certain operating instructions and a failure to foll ow these instructions carefully could result in erroneous data being produced by CIRCLY.1 Customer acknowledges and agrees that: (a) pavement design and engineering is a complex area and the CIRCLY is not desi gned as a substitute in any way for professional advice. Acknowledgement 22. . against any loss. unlawful or negligent act or omission of Customer. and (ii) All appropriate legislation and other relevant instruments. To the extent permitted by law.0 User's Guide (c) Whilst CIRCLY may be used by persons without a detailed knowledge of compute rs. an d (e) It shall obtain professional advice in relation to all results provided by C IRCLY. 23. employees and agents. demands. Customer shall fully indemnify and keep indemnif ied Mincad Systems.2 CIRCLY is licensed on the basis set out in this Agreement on the understand ing that to the extent permitted by law Mincad Systems is not responsible for the results of any actions taken. . (d) It shall manually check all results provided by CIRCLY for any anomalies. its officers. either by Customer or a third party relying on figures supplied or not su pplied by CIRCLY. including.CIRCLY 5. witho ut limitation: (i) the applicable engineering standards for paving and concrete. CIRCLY is designed to be used by persons who have a detailed knowledge of. costs. Indemnity Customer warrants that any materials supplied to Mincad Systems by Customer do n ot infringe Intellectual Property Right of any person. 22. taxes or liability whether direct or indirect arising out of: (a) use of CIRCLY. (b) a breach of this agreement by Customer. or (c) any wilful. expenses. with out limitation the relevant industry recognised engineering design guides. surface of natural or man-made stratified deposits. A cross-anisotropic material is assumed to have a vertical axis of s ymmetry. CIRCLY can also be used for other geotechnical applications such as foundation engineering and settlement analysis . Results can be easily exported to other applicat ion packages such as spreadsheets for further processing. Results can be obtained in tabular form or as report-quality plots on any printe r or plotter supported by Microsoft Windows. In many soil and rock engineering problems. CIRCLY has a user-friendly menu-driven interface that runs under Microsoft Windo ws. or a combination of both types. Typical runs take less than a second on Pentium PC s. thus eliminating the ne ed to constantly re-key information. CIRCLY has special features for the convenient mechanis tic analysis and design of pavements using state-of-the-art material properties and performance models. Anisotropies of this type have been observed in soil and rock deposits due to pr ocesses involved in their formation. The sys tem calculates the cumulative damage induced by a traffic spectrum consisting of any combination of vehicle types and load configurations. it is not necessary to approximate multi-wheel configurations by equivalent single loads. CIRCLY calculate s the stresses. loads are applied to the horizontal. The interfaces between the layers can be either ful ly continuous (rough) or fully frictionless (smooth). Databases are used for material properties and loadings. permitt ing the rational assessment of ultimate stability and the behaviour under working loads. In practice. strains and displacements that are developed in these systems. cross-anisotropic material properties can also be considered. loads may be applied to soil or rock pavement layers in the form of . 2004) that is widely used in Australia and New Zealand. Because the contribution o f each vehicle/load configuration can be explicitly considered.CHAPTER 1 Introduction Overview CIRCLY is a powerful package that analyses a comprehensive range of load types a cting on layered elastic systems. As well as the usual isotropic properties. CIRCLY is an integral component of the Austroads Pavement Design Guide (Austroads 1992. or near horizontal. For most problems the program uses less computer time than a finite element program. CIRCLY can also model non-uniform contact stress distributions. torsional wheel loads due to cornering. horizontal forces. The program allows all of these load types to be simulated for a circular loaded shape. foundation loads on footings. horizontal wheel loads due to traction and braking. moments about horizontal axes or contact stresses due to foundation roug hness.vertical wheel loads. Inp ut data for the program is much simpler than that required for most finite element programs. CIRCLY is based on integral transform techniques and offers significant advantag es over other linear elastic analysis techniques. . and the "gripping" load developed by pneumatic tyres on pavements. piers and rafts may be applied as vertical forces. In addition. such as the finite element method. 0 User's Guide This Australian designed system has been developed by the Melbourne company. For an overview of the new features of Version 5. If the cumulative damage is less than 1.0 see What's New in Version 5. Version 4.0. 0 was released in early 1999 and extended the software to include an automatic thickne ss design capability.1 was released in early 2003. proving its worth in thousands of design applications.0 (see "Overview" on page 15) Special Features for PavementEngineering CIRCLY has many features to facilitate pavement analysis and design. CIRCLY was first released in 1977 and handled polynomial type radial vari ations in contact stress and multiple loads which provide a much closer representation of the actual loading conditions (Wardle 1977). Wardle and Ger rard 1972).0 was released i n late 1996 and included many improvements. The damage factor for the ith loading is defined as the number of repetitions (ni) of a given response parameter divided by the allowable repetitions (Ni) of the response parameter that would cause failure. CIRCLY had its genesis in software developed at CSIRO for relatively simple loading cases (Harrison. CIRCLY was commercialised in 1988 by MINCAD Systems. Version 3. It has been in regular use in Australia and worldwide for more than two decades.0 was released in early 2004. including a major re-write of the integrati on algorithms and automatic sub-layer generation for granular materials. Version 5.4) was made in early 1996. i Ni The system is presumed to have reached its design life when the cumulative damag e reaches 1. Version 4. MIN CAD Systems. Cumulative Damage Concept The system explicitly accumulates the contribution from each loading in the traf fic spectrum at each analysis point by using Miner's hypothesis. A limited release of the fi rst Windows version (Version 2.CIRCLY 5. The Cumulative Damage Factor (CDF) for the parameter is given by summing the damage factors over all the loadings in the traffic spectrum: n Cumulative Damage =.0 the system has excess cap acity and . It is not necessary to approximate passes of different vehicles or axles to passes of an equivalent standard load. the material performance properties used in the design model..0 the system is predicted to fail before all of the desig n traffic has been applied. This approach allows analyses to be conducted by directly using a mix of vehicle or axle types. If the cumulat ive damage is greater than 1. the design repetitions of each vehicle/load condition.the cumulative damage represents the proportion of life consumed.. . and . The procedure takes account of: . . CIRCLY generates a file that can be read by most spreadsheet and technical graphics programs.Chapter 1 Introduction The current version of the software uses the cumulative damage concept to sum th e damage from multiple vehicle/load cases for one set of layered system material properti es. where N is the predicted life (repetitions) k is a material constant b is the damage exponent of the material e is the induced strain (dimensionless strain) Log-log relationships can be readily converted to the above form. .. CIRCLY is supplied with a comprehensive range of published performance models. vertical deflection. N = . The figure below is a sample cumulative damage plot produced by CIRCLY. Y ou can use your own performance equations by specifying values for k and b and the particul ar component to be used. CIRCLY represents models in the form: kb .. e. Material performance Generally most performance models may be represented graphically by a plot of to lerable strain versus load repetitions (generally by a straight line of 'best fit' on a log-log plot). for example vertical strain. etc. maximum tensile strain. CIRCLY can compute results from non-ver tical loads such as braking and cornering loads. a single pulse that reflects the overall loading on the axle group. . the traffic expressed in ESAs must be multiplied by a factor that depends on each ma terial type. Although the loads are usually vertical. Wheel Loadings The load on each wheel is defined by tyre contact radius and contact pressure (g enerally assumed to be the tyre inflation pressure). For further details see Thickness Design Capability (on page 33). 10) for each material type. ESA Multipliers For design methods such as Austroads that use an equivalent standard wheel appro ach. The 'load case' allows the loading for a given vehicle or axle group to be treat ed in more detail if required. and .0 User's Guide Traffic and Loading You define the anticipated repetitions over the design period for each vehicle o r axle group and 'load case'. Automatic thickness design You can automatically determine the optimum thickness of a given layer. The two ext remes of behaviour are .CIRCLY 5.g. Further d etails are given in Important Note about Damage Pulses (on page 67). For fur ther details see Damage Calculation Details (on page 31). multiple distinct pulses resulting from each axle. CIRCLY lets you specify the method to be used to calculate the damage. You can specify these multipliers (e. for shallow depths. Methods for handling Damage Pulses The damage that a given point in the pavement will experience during the passage of a multiple axle primarily depends on the depth below the road surface. for large de pths.. 1.1. This pro cedure is very fast and takes only a few seconds on a Pentium PC.. 11 CHAPTER 2 Overview of User Interface Introduction CIRCLY has a standard format Microsoft Windows menu. but most commands can be accessed directly from the toolbar as shown below: . dam CIRCLY32 cumulative damage results file (for plotting) Jobname.clo CIRCLY32 'printable' results file Jobname.. Closes the current job. You can also save your job under a different name by clicking on the File Menu. All the other files are generated automatically by the system: Jobname. Each i con corresponds to one of the main groups of data necessary to fully define a Job.prn CIRCLY32 raw results file (i. Opening and Saving Files You supply a 'Jobname' to use as the basis for naming all of the files associate d with a 'job' or analysis.e. prompting you to save any changes. open and save job files. then clickingSave As. strains.CIRCLY 5.0 User's Guide Creating. Icon Description Closes the current job. prompting you to save any changes. Three icons on the toolbar allow you to create. Creating and Editing Input Data The following seven icons allow you to create and modify your input data. If the job name is Jobname the following files are used Jobname. then creates a new job.this is used to save the details of your job.) Jobname.dmx CIRCLY32 results summary file (damage factors and critical strains) All of these files are text files that can be opened by standard text editors. then opens an existing job. etc.cls CIRCLY data file.cli CIRCLY32 input data file Jobname. Updates the current job file. . Alternatively. Running CIRCLY32 Analysis andPlotting Results Run Analysis This invokes the CIRCLY32 analysis. This is designed to elimin ate re-entry of data for design loads and material properties. the data for a commonly used material need only be entered into the sys tem once. If this data is subsequently modified.Chapter 2 Overview of User Interface Database Approach Some of the input data items are entered using very simple input forms. Most of the input data is handled using a relational database approach. all Layered systems that use that materia l and subsequently all Jobs that use those layered systems will automatically access t he modified material properties. The relational database approach gives maximum flexibility in data preparation. During a long analysis you can switch to ano ther application (CIRCLY will continue to run at a lower priority using Microsoft Win dows multitasking).. location for all data files (Defaults to the same directory that CIRCLY has been installed. Plot Results Usually. stress or strain component. vertical distances/depths below the surface of the pavement) and results can be plotted for a selected displacement. You can tailor each of the dat abases to contain specific sets of regularly used data.e. this command will produce a graph of the damage contribution from each vehicle type and the overall total (damage contribution from all the traffic). Options The Options screen allows specification of the following directory: .. as an option you can produce a graph of a selected displacement. For example. stress or strain component at your chosen Z-values (i.) . Detailed instructions on how to use the new features are given in How to Use New Austroads 2004 Features (on page 79). In what follows. .0 if you have used earlier versions such as CIRCLY 4. Changed methodology for sub-layering of unbound granular material. .CHAPTER 3 What's New in Version 5.. The Guide has undergone a major re-write over the last few years. Changed Subgrade Performance model for subgrade materials. Briefly. Support of Austroads 2004Pavement Design Guide The Austroads Pavement Design Guide (the full title is Pavement Design .0 or 4. Standard Axle modelled in full (Austroads 1992 uses only one side or half the ax le) . This section gives a quick overview of the new and improved features in CIRCLY 5 . more transparent and more efficient. . The technical content of the new Guide was finalized in June 2003 and that the Guide is expected to be published in the first quarter of 2004.. The 2001 Draft (Au stroads 2001) was the most recent published version at the time of writing this manual....1. Crossreferences to the rest of the manual show you where to look for information on t hese topics. .A Guide to the Structural Design of Road Pavements) was first published in 1992 (Austroads 1992 ).0 implements the following changed features in the Guide: . CIRCLY 5.0. Introduction of Select Fill as a particular type of unbound granular material.0 Overview You will find many improvements in CIRCLY 5. These changes are outlined in more detail in Overview of Austroads 2004 Features (on page 73). Latest improvements include new features to make designing pavements easier. Project Reliability as chosen by the designer. the new Guide wil l be referred to as the 2004 Guide. . exported and printed.0 User's Guide New "built-in" Graphics Engine CIRCLY now uses its own "built-in" Graphics Engine to create on-screen graphics almost instantaneously. Here is a sample Cumulative Damage graph: You can choose a graph for a different layer (without re-analysing the system): . The graphics can be customized.CIRCLY 5. In most c ases. results for different layers or Z-depths in a layered system can be created with out reanalysing the system. Click on Customizat ion Dialog to customize the graph: .0 17 Here is a sample "Three-dimensional" graph of vertical displacement: You can customize the graph via the context-sensitive graph menu that drops down when you right click with the mouse pointer anywhere on the graph.Chapter 3 What's New in Version 5. . etc.0 User's Guide This lets you customize many of the graph parameters such as Minimum and Maximum axis values. subgrade stabilization and the like. Cost Calculation The unit costs for the materials laid and constructed in the layers can be speci fied using a combination of both a volumetric (or weight) component and an areal component. The areal component can also be used in circumstances where the relationship between total layer cost and thickn ess has a non-zero component for zero thickness. T he areal component lets you take account of costs that are primarily a function of area.CIRCLY 5. such as surface treatments. Chapter 3 What's New in Version 5. you can automatically design the thickness of another layer. Additionally. for each combination of those layer thic knesses. Minimum Total Cost Automatically generated plot: Total Cost vs. Layer 2 Thickness . By combining Automatic Parametric Analysis with the Cost Analysis feature you ca n finetune layer thicknesses to optimise construction cost. For example.0 Automatic Parametric Analysis Automatic Parametric Analysis lets you automatically loop through a range of thi cknesses for one or two nominated layers. you can have Layer 2 vary from 100 mm to 200 mm in steps of 10 mm. this worked example a ssumes that most of the input data is already in the appropriate databases. .CHAPTER 4 How to Start Using CIRCLY Getting Started: Assembling andRunning a Job In the interests of providing instant hands-on experience. Start a new Job file Click on the button. You will be usin g an existing traffic spectrum and an existing layered system. Follow this procedure: 1. This will bring up the list of available Traffic Spectra: If you have not already selected a spectrum the blue highlight will be positione d on the first entry.Unbound Granular Pavement by moving the mouse pointer to this line and then clicking on it. Click on the Layered System tab. Click on the Spectrum tab. 2. 3. Select Traffic Spectrum Click on the button. Specify Layered System button.Example 1 . Select Austroads 2004 .CIRCLY 5. This will bring up the list of available Layered Systems: Click on the .0 User's Guide Enter your Job Name and Job Title (this is used on the graphs). 4.. This screen has fields for specifying the locations for which results are to be computed.. Specify Coordinates for Results Click on the button. .Unbound Granular Pavement by moving the mouse pointer to this line and then clicking on it.Example 1 . Two alternative formats are available for specifying the points to be used for r esults calculation: . Select Austroads 2004 . A grid of points with uniform spacing in both the X-direction and the Y-directio n Enter the data as shown below. An array of equally spaced points along a line parallel to the X-axis . the blue highlight will be po sitioned on the first entry.Chapter 4 How to Start Using CIRCLY If you have not already selected a Layered System. Run the CIRCLY32 analysis Click on the button. To comply with the Austroads Guide. as shown below. .0 User's Guide The data entered as above will create a line along the X-axis from (0. Analyses typically take about a second on a Pentium PC.0) at intervals of 165 mm. The sub-section Assumed number of damage pulses per movement is dealt with later in Important Note about Damage Pulses (on page 67).CIRCLY 5.0) to (165 . When the CIRCLY32 analysis starts you may see a blue "progress bar" at the botto m left corner of the screen. the dimensions are in millimetres (see Units (on page 47) for further details). This invokes the CIRCLY32 analysis. When the CIRCLY32 analysis is complete the results for the damage factor (CDF) w ill be transferred to the top table on the screen. This will generate a graph of the results: .Chapter 4 How to Start Using CIRCLY 25 6. Plot the Results Click on the button. You do this via the context-sensitive graph menu t hat drops down when you right click with the mouse pointer anywhere on the graph: . You can also copy the graph to the clipboard and then paste into another applica tion such as Microsoft Word or Powerpoint.0 User's Guide You can print a copy of the chart by clicking on the Print icon on the toolbar.CIRCLY 5. The 'Export Dialog' lets you export to a variety of formats. but for most purposes select 'Metafile' to ensure that the graphics are scalable.Chapter 4 How to Start Using CIRCLY 27 Then click on 'Export Dialog'. . The X-axis is usually taken as the direction transverse to the direction of vehi cle travel. .CIRCLY 5. An array of equally spaced points along a line parallel to the X-axis. The global coordinate system is also used to describe the resultant displacements and stress and strai n tensors. Figure 1: Global Coordinate System The Z-axis is vertically downwards with Z = 0 on the pavement surface. A grid of points with uniform spacing in both the X-direction and the Y-directio n. the layered system geometry and the points below the road surface at which results are required. The Y-axis is then parallel to the direction of vehicle travel. . Two alternative formats are available for specifying the points to be used for r esults calculation: .0 User's Guide Global Coordinate System A global coordinate system is used to define load locations... Chapter 4 How to Start Using CIRCLY X Y 0 Direction of Travel Xmin XmaxXdel Results points Figure 2: Coordinates for results defined by a line of equally spaced points X Y 0 Xmin XmaxXdel Ymax Ymin Ydel Results points Direction of Travel Figure 3: Coordinates for results defined by a uniform grid of points . you will calculate the damage factors (CDF) for your pavement. Normally. between one layer (the subgrade) and three layers (asphalt surfacing. you can calculate results for any given displaceme nt. You can automatically determine the optimum thi ckness of a given layer.0 offers a number of calculation options. Alternatively. cementstabilised layer and subgrade) will have performance criteria associated with them. This will bring up the following screen: 1 2 3 .CHAPTER 5 Alternative Calculation Options Overview CIRCLY 5. stress or strain component at selected Z-values (depths below the road surface). Click on the button. Damage Calculation Details Typically. the key features on the scree n (the numbers refer to the screenshot above) are: 2 This table is a summary of the layered system including material titles and cu rrent thicknesses. . Also the current Cumulative Damage Factors (CDFs) will be shown if the problem has been run previously. When operating in 'calculate damage factors' mode. Calculate damage factors (CDF).CIRCLY 5. 3 This table is a summary of the properties for those layers that have a perform ance criterion.. The current thickness of any layer can be chang ed from this screen. 1992. These multipliers are necessary to take account of the material type and t he actual traffic mix. S ection 7. .5). Here the Traffic Multipliers are multipliers that are used in Equivalent Single Axle (ESA) calculations (as described in the Austroads Pavement Design Guide. The multipliers are simply used to increase the ESA count (in the ' Movements' field) that is specified in the Traffic Spectrum screen..0 User's Guide 1 Two alternative calculation options are available: . Calculate selected results at user-defined Z-values (see Calculate Selected Resu lts at User-defined Z-Values (on page 34)). Here a tick ( ) denotes that the layer will be included in the maximum damage factor calculation. 1 The thickness design capability is invoked by clicking on the checkbox that is l abelled 'Design thickness of layer highlighted below'. the design will use the maximum damage factor (CDFmax) from all the layers that have a performance criterion. 2 You select the layer you wish to design by moving the mouse pointer to the appropriate layer and clicking the mouse button once. The tick-box can be toggled on and off by clicking on it. typically taking a few seconds on a Pentium PC. This pro cedure is very fast. 1 2 3 . it may be necessary to ignore one or more layers when calculating the maximum damage factor.0 by varying the thickness of the highlighted layer. 3 By default. The design involves bringing the maxim um damage factor to 1. In some circumstances. The layer selected will be highlight in blue.Chapter 5 Alternative Calculation Options Thickness Design Capability You can automatically determine the optimum thickness of a given layer. you may need to calculate selected results (displacements . stresses and strains) at selected Z-values (depths). stress or strain component. so that no constraints are applied. or these fields can be left blank. damage factors are not calculated. If a specified maximum or minimu m thickness limit prevents attainment of a CDF of 1.CIRCLY 5. the CDF for the thickness limit will be computed.0. Specify first convenient Z-values an d then plot results for a selected displacement. This will bring up the following screen: 2 1 6 3 4 5 . Calculate Selected Results at Userdefined z-Values In some circumstances. When you use th is option.0 User's Guide Minimum and maximum thicknesses can be specified for each layer. Click on the button. g. 5 Now you can define the Z-values. Each Z-value is added by clicking the New butto n You can delete any entry by clicking on it and then clicking the Delete button. You can then define the component type (e. displacement. or below th e interface). A drop down list of alterna tives will appear: Click on the Component that you wish to use. 4 6 . etc.g. vertical. 2 You can choose the component that is to be plotted by first clicking on the 'Component type' tab. When a Z-value coincides with the interface between two layers.) is specified by clicking on the down arrow on the right hand side of the 'Component' combo box. you can specify which side of the interface is to be used (i. strain etc.. 3 The actual component (e.e. .) by clicking on the down arrow on the right hand side of the 'component typ e' combo box. This will invoke this drop down list: Click on the component type that you wish to use. above the interface.Chapter 5 Alternative Calculation Options 1 This option is invoked by clicking the button that is labelled 'Calculate select ed results at user-defined Z-values'. Click on the button.0 can automatically calculate Total Cost for a pavement from the unit c osts of materials in each layer.CHAPTER 6 How to Use Advanced Features Cost Calculation Calculation of Total Cost CIRCLY 5. This will bring up the following screen: Total CostTotal Cost 1 1 Click on the Calculate Cost checkbox . The areal component can also be used in circumstances where the relationshi p between total layer cost and thickness has a non-zero component for zero thickne ss.CIRCLY 5. i) ($/m2) The Unit Volumetric Cost can be defined in terms of: 1 Cost/Volume. i) (mm) + Unit Areal Cost (layer no. subgrade stabilization. Unit Material Costs Unit Material CostsUnit Material Costs The Total Cost for a given layer is calculated as follows: Total Cost (layer no.0 User's Guide Material Costs The unit costs for the layers can be specified using a combination of both a vol umetric (or weight) component and an areal component. or 2 Cost/Weight and the density of the material (Weight/Volume). . etc. i) ($/m2) = Unit Volumetric Cost (layer no. i) ($/m3) x Th ickness (layer no. The areal component lets you take acco unt of costs that are primarily a function of area such as surface treatments. or 2. you can have Layer 2 vary from 100 mm to 200 mm in steps of 10 mm. This will bring up the following screen: 1 1 Click to switch on Parametric Analysis. One Independent Variable.e. you can automatically design the thickness of another layer. This will bring up the following form: 1 2 3 4 1 This combo box lets you specify the number of Independent Variables (i. Click on the button. Two Independent Variables. Combining this with the Cost Analysis feature lets you fine-tune layer thicknesses to optimize construction c ost. the number of Layers for which you are varying the thickness): 1. for each combination of those layer thic knesses. . 2 This section gives the details of the first Independent Variable. Additionally. For example.Chapter 6 How to Use Advanced Features Automatic Parametric Analysis Automatic Parametric Analysis lets you automatically loop through a range of thi cknesses for one or two nominated layers. click the combo box ( 1 on the screenshot belo w).CIRCLY 5. To use two Independent Variables. 1 2 3 4 2 This section gives the additional details for the second Independent Variable 3 Here you specify which layer (thickness) is to be used as the second Independe nt Variable 4 Here you specify the range of thicknesses to be used for that layer: minimum to T2 step The thickness will range from T2 maximum in steps of T2. 4 Here you specify the range of thicknesses to be used for that layer: minimum to T1 step The thickness will range from T1 maximum in steps of T1. .0 User's Guide 3 This lets you choose which layer (thickness) is to be used as the first Indepe ndent Variable. Open the sample file "Economic Analysis . Class 4 = 3 . Step 1. Step 2. Type H 20.Chapter 6 How to Use Advanced Features Example Cost Optimization In this example you will use the Automatic Parametric Analysis feature to automa tically loop through a range of thicknesses for one layer (Layer 2) and to determine which th ickness has the minimum Total Cost. 2 1 14...Pavement Option B2". . Thickness ThicknessThickness Unit Cost Unit CostUnit Cost T TT1 11= 40 mm = 40 mm= 40 mm $288 / $288 /$288 / m mm3 33 T TT2 22= ? = ?= ? $288 / $288 /$288 / m mm3 33 T TT3 33= ? = ?= ? $50 / m $50 / m$50 / m3 33 Asphalt: Size Asphalt: Size Crushed Rock: Subgrade. For each Layer 2 thickness. CBR . Type T 20 mm . you will get CIRCLY to autom atically design the thickness of Layer 3. 4 Here you specify the range of thicknesses to be used for Layer 2: For this example. you will let Layer 2 vary in thickness from 160 mm to 230 mm i n steps of 10 mm. Step: 10. This will bring up the following form : 1 2 3 4 1 This combo box lets you specify the number of Independent Variables (i. . For this example change this to "2". One Independent Variable. Now set the automatic thickness design feature to Layer 3. (as you are varying the thickness of Layer 2). . Step 3. the thickness of L ayer 2.CIRCLY 5. 3 This lets you choose which layer (thickness) is to be used as the first Indepe ndent Variable. 2 This section gives the details of the Independent Variable.0 User's Guide 1 Make sure the Calculate Cost check-box is ticked. Enter the following values: Minimum: 160. For this example you will use the default. 2 Click the Parametric Analysis check-box. the number of Layers for which you are varying the thickness). Maximum: 230..e. .. 2 1 1 Click the check-box labelled 'Design thickness of layer highlighted below'. When the analysis is finished. Minimum Total Cost This plot shows the Minimum Total Cost condition for Layer 2 thickness is 220 mm (to a resolution of 10 mm). Now click on to run the analysis. 2 Click anywhere on the Layer 3 row.Plot the Total Cost vs Layer 2 thickness. Step 4. Click in the "Minimum Thickness" cell on this row and enter 100 (mm).Chapter 6 How to Use Advanced Features Click on the "Summary" tab (left of the "Variables" tab). click on to plot the results. . . Layer 2 thickness.Plot the Layer 3 thickness (Design Layer) vs. Layer 2 thickness. Select Size 20 Type T .40km/h (This is Layer No.Plot the CDF (for Layer 2) vs. Click on the Parameter combo box. Step 6.CIRCLY 5. Click on the Layer combo box. . Select CDF (Select Layer =>). Step 5.. Click on the Parameter combo box.0 User's Guide . 2) . the Layer 3 thickness would be 39. Comments on these results.Chapter 6 How to Use Advanced Features 45 Select Thickness (Layer used for Thickness Design). If the Layer 2 thickness is 160 mm or less. If there was no Minimum Thickness constraint. . the Layer 3 thickness is 100 mm. 6 mm.91. the "designed" thickness of Layer 3 exceeds 5000 mm. If the Layer 2 thickness is 220 mm. This would be inconsistent with the Austroads (1992) sub-layering requirement that th e minimum thickness of a sub-layer is 50 mm. Therefore a Layer 2 thickness of less than 160 is not viable if support ed by the Layer 3 material. because of the Minimum Thickness constraint and because the CDF is 0. These units must be used for a ll Austroads applications involving sub-layering of granular materials. mm Displacement Elastic modulus. Quantity Units Length. all data must be in a consisten t set of units.mm Strain mm/mm This system of units is consistent with the Austroads Pavement Design Guide and has been used for all the data files provided with CIRCLY. Quantity Metric* Metric Metric Imperial Imperial Length. MPa Pressure Force N Moment N. Other compatible systems of units can be used as shown in the following table. MPa mm m m ft in Displacement Elastic modulus. the strains are dime nsionless and the displacements will have the same units as the load dimension and the layer t hicknesses. a s long as sub-layering of granular materials is not used. kPa MPa lb/ft2 lb/in2 (psi) Pressure . The recommended system of units is given below.CHAPTER 7 How to Modify the Databases Introduction Units In order for CIRCLY to deliver coherent results. Output stresses will have the sa me units as used to define the loading stresses and the elastic moduli. in Strain mm/mm m/m m/m ft/ft in/in *This system of units must be used for Austroads applications involving sub-laye ring of granular materials.0 User's Guide Force N kN MN lbf lbf Moment N. Sign Convention Compressive direct stresses and strains are considered to be positive. Displacements in negative coordinate directions are considered to be posit ive. Positive shear stresses are defined on the basis that both the stress and strain tensors obey t he right hand rule.ft lbf. The sign conventions used in the rectangular coordinate system and cylindrical local coor dinate system are illustrated below. Hence a load causing a positive stress acts in the positive coordinate direction.mm kN.CIRCLY 5.m MN. Figure 4: Sign Convention .m lbf. To create a new layered system.. The Figure below illustrates the relational database concept for the elastic mat erial properties. . A consequence of the relational database approach is that data should generally be prepared from the 'bottom up'. If this data is subsequently modified.Chapter 7 How to Modify the Databases Overview of Database Approach The relational database approach is designed to eliminate re-entry of data for d esign loads and material properties. these steps must be followed: 1 Create any materials that are not already in the Elastic Materials database. Figure 5: Relationships between elements in Layered System databases A similar hierarchy applies for the Traffic database. all Layered Systems that use that material and subsequently all Jobs that use those Layered Systems will automatically access the modified material properties. This means that: . . For example. Each load group referenced by the Traffic Spectrum is linked to a record in the Load Group data. the data for a commonly used material need only be entered into the system once. Elastic Materials Properties data must be entered before the Layered System Components data. each of the components that make up a Layered System is linked to entries in the Elastic Material Properties database via an ID (index) field of u p to 10 characters. 2 Create a new entry in the Layered Systems database. Load Group data must be entered before the Traffic Spectrum Components data. Here.. NL Layer No. The "Layered System" and "Materials" Databases Overview of Layered System and Material Properties CIRCLY models road pavements as a system of layers. The layered system consists of one or more layers. smooth).e.50 CIRCLY 5. Inte rfaces between the layers can be either fully continuous (rough) or fully frictionless (smooth). 2 Rough rigid base Smooth rigid base Semi-infinite base Layer No. each with differing elastic properties.0 User's Guide 3 Define each of the Materials and thicknesses for each of the Layers using the Layered System Components database. Layer No. The layer interface planes ar e horizontal and each layer is assumed to be of infinite extent in all horizontal directions. or a combination of both types... The bottom layer may extend to a finite depth or to a semi-infinite depth (see the figure b elow). rough) or fully frictionless (i. If the bottom layer is of finite depth. Worked examples in the following sections show how you can create new data.e. it is assumed to rest on a rigid base. and the contact can be either fully continuous (i. 1 8 . vh). Data values for all five constants are rarely available.Chapter 7 How to Modify the Databases Cross-anisotropy and isotropy in road pavement materials The elastic material in each layer of the pavement/road structure is assumed to be homogeneous and of cross-anisotropic or isotropic symmetry.vh > 0 For isotropic materials the restrictions become: E > 0 0. In general. the Poisson s ratio (. the Poisson s ratio (.h syy -. A cross-anisotropic material has an axis of symmetry of rotation.. these properties are di fferent from those in the direction parallel to the axis. > -1.e.0 To be able to model a cross-anisotropic material you need to specify five consta nts: the vertical Elastic modulus (Ev).h)/Eh) sxy exz = (1/f) sxz eyz = (1/f) syz The moduli and Poisson's ratios are related by the following equation: .h sxx + syy -. radial directions).5 > . the elastic properties are equivalent in all directions perpendi cular to the axis of symmetry (in horizontal. The stress-strain relations for a cross-anisotropic material in a particular lay er are: exx = (1/Eh) (sxx -.h > -1 1-.hv szz) eyy = (1/Eh) (-.vh syy + szz) exy = ((1+.vh/Ev = .hv/Eh The condition that the strain energy must be positive imposes restrictions on th e values of the elastic constants: Eh > 0 Ev > 0 f > 0 1 > . . which is assum ed to be vertical. the horizontal Elastic modulus (Eh).vh sxx -.h) and the Shear modulus (f).hv szz) ezz = (1/Ev) (-.hv.h-2. whereas isotropic materials have th e same elastic properties in both the vertical and horizontal directions. In the Austroads pavement design method (1992 and 2002) cross-anisotropic proper ties are used for subgrade materials and unbound granular aggregates and isotropic proper ties are used for bound materials such as asphalt and cemented materials. i. . only the Elastic modulus and Poisson s ratio need to be e ntered. Now you can define the details of the layers in your layered system.5 Ev . . You should now type in your ID (index) field of up to 10 characters and a descriptive title (up to 72 c haracters). Click on the Layered System tab.) In this case. For this example you can type in 'MyLayers' as the ID and 'Example of creating a new Layered System' as the Title. the material is defined simply by the vertical Elastic modulus. A dialog box will appear as shown below. Click the OK button. as they are assumed to be the same in all directions. Click on the New button.vh = .h = . .0 User's Guide The Austroads Pavement Design Guide uses the following simplifications to model subgrade and unbound granular materials: Eh = 0.. and a single Poisson's ratio.CIRCLY 5. For isotropic materials. Creating a new Layered System Click on the button. Ev . f = Ev/(1+. 1 . You can specify any interfaces as full y frictionless. Click on the New button. click on the appropriate line then click the OK button. A list of available materials will now appear. and working downwards through the pavement. or a combination of both types. A new record will be added at the bottom of the table and the cursor will be pos itioned in the Thickness column.0. The subgrade will extend to an infinite depth if you enter the t hickness as 0. You will now choose the Material Type. i.e.. interfaces between the layers can be either fully continuous (rough) or fully fr ictionless (smooth).Chapter 7 How to Modify the Databases 53 Defining the Layer properties You add the layers working from the top of your pavement system. as shown below. As explained in Overview of Layered System and Material Properties (on page 50). Select the required material by c licking on the appropriate line. starting with asphalt or cemented material. Enter the layer thickness. You repeat this process to add as m any layers as you require. then click on the OK button. A pop-up list will appear. To select the Material Type. Note that for a semi-infinite subgrade both 'Rough' and 'Smooth' are equivalent.0 User's Guide By default. You can then click on the down arrow at the right of the cell to select a 'Smooth' inter face. Then you can c hange the settings that need to be different. Duplicating a Layered System Sometimes you may want to create a Layered System that is similar to an existing one. You will then see a form that will let you defi ne the ID and Title of the newly duplicated Layered System: . all interfaces are assumed to be rough. You can change the condition for the interface at the bottom of a given layer by clicking in the 'Interface Type' cell. The Duplicate function lets you duplicate an existing Layered System.CIRCLY 5. Move the blue highlight to the Layered System that you want to duplicate: Then click the Duplicate button. For this example.Chapter 7 How to Modify the Databases 55 The ID and Title that are provided are based on the original Layered System . Adding a new Elastic Material Click on the button.5' for the Title. You now choose the material type to be used.ma ke sure that you modify the Title.5'. Click on the Elastic Materials tab. Click on the material type combo bo x as shown below to select from the available material types. as shown below. Click on 'Subgrade (Aus troads 2004)' for the Material Type. you can type in 'Sub_CBR2. the ID is used to sort the data. As you can see from the example be low. Type i n 'Subgrade. After you click the OK button you will be taken to the Layered System Components table so that you can make your changes. . CBR=2. A dialog box will appear. You should no w type in your ID (index) field of up to 10 characters. Click the OK button. Cl ClClick ickick he hehere to re tore to se seselec leclect tt Ma MaMate teteri riria aal ll Ty TyTyp ppe ee Click on the New button. Then type in the moduli and Poisson's ratios as follows: Ev = 25.0 Eh = 12.45 (= .5 (= 0. A new record will be added to the table.)) The new record should be as shown below: . To selec t a Performance Criterion make sure the checkbox next to Use performance criterion is checked. then click on the appropriate performance criterion.vh = .CIRCLY 5.24 (= Ev/(1+. Select 'Anisotropic' in the column head ed 'Aniso?'. Click on the OK bu tton.h = 0.) f = 17.5 Ev) .0 User's Guide You will now be given an opportunity to select a Performance Criterion. Click on the material type combo bo x (as shown on the first screenshot in Adding a new Elastic Material (on page 55)) to select from the available material types. N = RF µe . You now choose the material type to be used. For this example. Click on the New button.Chapter 7 How to Modify the Databases Adding a new Performance Criterion For this example we consider the Shell asphalt fatigue criterion: 5 . 0. Now type in your ID (index) field of up to 10 character s and the . . where RF is the Reliability Factor µe = maximum tensile strain (in units of microstrain).9 and Smix = 1600 MPa. For this example click on 'Asphalt'. The Reliability Factor is assumed to be 1. 6918(0. Click on the Performance tab.08) . .856 VB + 1.36 .0 if you are using the Austroads 1992 Pavement Design Guide. and Smix= mix stiffness (Elastic modulus) in MPa. Smix . VB = percentage by volume of bitumen in the asphalt. so that the above equati on simplifies to: N = [ 5889 / µe]5 To enter this data click on the button. assume VB = 12. Otherwise the value of the Reliability Factor is automatically han dled by your choice of Project Reliability (see How to Use Project Reliability (on page 80)).. 9%' for the Title. For this example type in 'Asph1600' for the ID.Title (up to 72 characters). Click the OK button. . Typ e in 'Asphalt1600 MPa. Vb=12. The Location field defines the location (relative to a layer of this material) a t which the criterion is to be applied. As CIRCLY assumes that the fatigue relationship is of the form N = [k / e]b . For this example Location should be 'Bottom'.. Click on the button to choose between Top and Bottom .0 User's Guide A record will be added to the table and you can type in the relevant data as fol lows: The cursor will now be in the component field.0. there will be a slider bar on the rig ht hand side.CIRCLY 5. length/length. Horizontal Tensile Strain (maximum horizontal tensile strain). You can move down the list by clicking on the down arrow or by dragging the slider d own. You can select the component from a dropdown list by clicking on the button. If there are more entries than will fit in the listbox.e. Here you specify the particular displacement.005889 and Exponent (b) will be 5. The new record should be identical to the bottom row in the figure below: . mm/mm). The entries for the remaining two parameters define the fatigue relationship N = [5889 / µe]5 Note carefully that strains in CIRCLY must be specified in dimensionless units ( i. stress or strain component to be u sed. the parameter µ (micro) must be replaced by 10-6 giving: N = [k / e]5 So Constant (k) will be 0. For this example select the Max. Chapter 7 How to Modify the Databases Adding a new Material Type You can add new material types. . Click New to create a new entry. To add a new material type. click the checkbox next to use sub-layering . Click on the button. You will now choose the Generic Material Type for your new Material Type: You will now be given an opportunity to select a Sub-Layering scheme. A dialog box will now appear and you can enter the ID (index) field of up to 10 characters and Title field (up to 72 characters). To select a SubLayering scheme. Clic k the OK button. then click on the ap propriate sub-layering scheme. Click on the OK button. Click on the Material Types tab. Depending on whether or not the components you need already exist.. the steps req uired are described in the following sub-sections. The databases form a hierarchy: .0 User's Guide The "Loads" and "Traffic Spectrum" Databases Introduction Four inter-related databases are used for the Traffic data. click on the button. . If there are more entries than will fit in the listbox there will be a slider bar on the right. Click New to create a new entry. A dialog box will now appear and you can enter the ID (index) field of up to 10 characters and Title field (up to 72 characters). Adding a new Traffic Spectrum If the Traffic screen is not already active. . The Spectrum Components Table will now appear. Now define your spectrum components: Click New for each vehicle model you wish to include. Clic k the OK button. Enter the number of vehicle movements (or passages) over the d esired .. Click on the Spectrum tab. This will activate a pop-u p list of possible choices. You can move down the list by clicking on the down arrow or by dragging the slider down. You finally select the vehicle by double clicking on it. Traffic Spectrum. Load Locations. . A new record will be added at the bottom of the table and the cursor will be pos itioned in the Movements column.CIRCLY 5... You can move the highlight to the vehicle that you wish to use by positioning the mouse pointer on it and clicking once. Traffic Spectrum Components. Load Groups. design life. . Move the blue highlight to the Traffic Spectrum that you want to duplicate: Then click the Duplicate button.Chapter 7 How to Modify the Databases 61 Duplicating a Traffic Spectrum Sometimes you may want to create a Traffic Spectrum that is similar to an existi ng one. The Duplicate function lets you duplicate an existing Traffic Spectrum. Then you can change the settings that need to be different. After you click the OK button you will be taken to the Traffic Spectrum Componen ts table so that you can make your changes. You will then see a form that will let you defi ne the ID and Title of the newly duplicated Traffic Spectrum: The ID and Title that are provided are based on the original Traffic Spectrum make sure that you modify the Title. . with axes X. y. Note the use of uppercase X. However. whil e 'local' coordinate systems are used to describe each of the loads. In terms of the 'global' coordina te system the origin of each 'local' coordinate system is specified by Xload. For loads that are symmetrical about a horizontal axis this axis is taken as the x-axis. Each 'local' coordinate system may be cartesian (x. Yload. The Z-axis in the positive direction is taken as vertically downwards. . z for Local coordinates. Z. for convenience. You can choose the origin of the 'global' coordin ate system to be any point on the upper surface of the layered system and the X and Y axes as any two mutually perpendicular axes that lie in this horizontal plane. z) and has its origin at the centre of the load it describes. it may be taken as parallel to the X-axis so that .0 User's Guide Coordinate System for Loads The most common type of load modelled in CIRCLY is a circular area over which a uniform vertical pressure is applied. which is dealt with in Wardle (2004) . it is possible to model more complex loads ind uced by breaking and turning movements of vehicles. For loads that are symmetrical about their centre point the x-axis may have any orie ntation. The location and orientation of a load are therefore specified by Xload.load is then zero. y. Z for Global coordinates and lowercase x. z) or cylindrical (r.CIRCLY 5. Y. Y. The 'global' system i s cartesian. Yload a nd . though. This load typically represents the contact of a ty re on the surface of the pavement. Figure 6: Global and Local Coordinate Systems . The location of the circular load is described by a global coordinate system.load) between the directions of the X-axis and th e x-axis. The orient ation of the load is defined by the angle (.load.. Click on the Load Groups tab. Click the OK button. . For this example type in 'TA-DW' as the ID and 'Tandem axle with dual wheels' as the Title. a Vehicle or Axle Group) Click on the button. Click on the New b utton.Chapter 7 How to Modify the Databases Adding a new Load Group (i. The example given here is for a tandem axle with dual wheels. A dialog box will appear as shown below..e. Type in your ID (index) field of up to 10 characters and a descriptive title (up to 72 characters). CIRCLY 5.0 User's Guide A record will be added to the table and you can enter the relevant data as follo ws: Field name (Heading) Value Explanation Plot Label TA-DW Label used by legend in graphs (Up to 72 characters) Rows 2 Number of rows (axles) in main gear (this is the NROWS parameter described in Important Note about Damage Pulses (on page 67)) Type 1 A flag to indicate type of load (1=Vertical. generally assumed to be the tyre inflation pressure (MPa).0 If this parameter is zero the contact stress will be uniform. Non-zero values give non-uniform contact pressure distributions as described in Program CIRCLY Theory and Background Manual. enter the reference stress referred to in the Program CIRCLY Theory and Background Manual. Exponent 0. If you are using an advanced load type. . for other values see Program CIRCLY Theory and Background Manual) Radius 92.75 For Vertical loads (Type=1) use the tyre contact pressure. The entries should look like this: You should now specify the wheel locations.1 Radius of tyre contact area (mm) Stress 0. See the note Important Note about Axle Locations (on page 65) below for s pecial information about defining axle locations.. For the Tandem axle. so that the gear centroid of gear number 1 is on Y = 0 (see Important Note about Damage Pulses (on page 67) for further d etails). and the X and Y coordinates of each wheel.Chapter 7 How to Modify the Databases Defining Load Locations (i. The scaling factor is normally 1.0 . If it is not the one you have just defined. dual wheels gear layout (TA-DW) shown above. .LOAD in Figure: Global and Local Coordinate Systems. click on the button. Check the descriptive title above the table to make sure that you are referring to the correct Load Group. Click on the Load Locations tab. It is essential that the gear numbers are correctly specified. Click New for each wheel and enter the gear number. This is used to shift the Y-coordinat es of the wheels for the combined pulse option. Theta corresponds to . the entries in the table should be similar to the table below. Theta is only used to define the force or moment direction for non-standard load s such as braking loads. Wheel positions) If the Load Groups screen is not already active. as described. click on the Load Groups tab.other values allow for a variation in conta ct pressure from wheel to wheel. click on the appropriate record within the Load Groups tabl e and click onLoad Locations again.e. Note that the wheels making up a given gea r can be in any order. The gear numbers are used for calculating the centroid of gear number 1. Important Note about Axle Locations Make sure gear number 1 has an axle on Y = 0. 0 User's Guide Y Direction of Travel (-165.-1320) (-165.CIRCLY 5.0) (165. dual wheels) .-1320) Axle 2 Figure 7: Example wheel layout (Tandem axle.0) Axle 1 0 (165. one pulse per axle is selec ted. relative to the axle spacing. which is sp ecified in the ROWS column of the Load Groups section of the Loads database. you specify 'combined pulse for gear' and CIRCLY will automatically shift the load coordinates so that the origin is at th e centroid of the gear. CIRCLY relies on you to specify one set of axles at Y = 0 as shown on Figure: Ex ample wheel layout (Tandem axle. In this case. CIRCLY then computes the damage pulse beneat h the centroid of the gear due to the strain contributions for all wheels of the vehic le. X Y 0 Direction of Travel Axle 1 Axle 2 Figure 8: Automatic shift of Y-coordinates for pulse for gear case combined . and ignores the number of axles in the group. then multiplies the computed damage by the number of axle s in the axle group (NROWS). relative to axle spacing. However. the maximum strain will generally occur under the centroid of the gear. dual wheels). for large depths. NROWS refers to the number of axles in the gear. CIRCLY then computes the damage beneath that axle due to the strain contribution s for all wheels of the vehicle.Chapter 7 How to Modify the Databases Important Note about Damage Pulses The damage that a given point in the pavement will experience during the passage of a multiple axle will primarily depend on the depth that the given point is below t he road surface. as shown in the Figure below. For shallow pavement depths. CIRCLY automatically shifts the position of the load coordinates if you specify 'combined pulse for gear'.0 User's Guide You must decide whether the pavement is deep or shallow relative to the axle spa cing. You specify how to deal with the gear by clicking on the button to open the Coordinates for Results screen. This screen has a sub-section for specifying the locations at which results are to be computed and the method for treating the damage pulse s. . Computation of the damage at intermediate depths requires judgement based on a knowledge of the strain pattern.CIRCLY 5. regardless of whether CIRCLY or other analysis methods are used. . Two alternative formats are available for specifying the points to be used for r esults calculation: . . An array of equally spaced points along a line parallel to the x-axis. ..Chapter 7 How to Modify the Databases Coordinates for Results Click on the button. This screen has fields for specifying the locations for which results are to be computed and the method for treating damage pulses. A grid of points with uniform spacing in both the x-direction and the y-directio n. CHAPTER 8 Appendices . No attempt is made to comprehensively describe all the features. These notes should be read in conjunction with Austroads 2004. The development of the new features in CIRCLY relating to the Guide was based on the April 2003 Draft. 199 2). The technical content of the new Guide was fin alized in June 2003 and that the Guide is expected to be published in the first quarter of 2004. 2001). The Guide has undergone a major re-write over the last few years. For convenience. .Overview of Austroads 2004 Features The Austroads Pavement Design Guide (the full title is Pavement Design . culminating in the release of the 2001 Draft (Austroads. we use the convention that Austroads 1992 is the original Guide and that Austroads 2004 is the new Guide. The following notes assume that you are already familiar with the original Guide . but the main differences with the ori ginal Guide are highlighted.A Guide to the Structural Design of Road Pavements) was first published in 1992 (Austroads. whereas Austroads 1992 uses on ly one half of the Standard Axle.0 User's Guide Model of Standard Axle The Standard Axle Load consists of a dual-wheeled single axle. This figure shows the layout of the wheels and their respective positions along the CIRCLY x-axis.CIRCLY 5. Austroads 2004 uses a full Standard Axle Loading. applying a load o f 80 kN. Figure 9: Model of Standard Axle . 000 85 Main Road: lane AADT>500 85 Other Roads: lane AADT<500 80 Material Properties Sub-layering Unbound Granular Materials Sub-layering is required for granular materials placed directly on the subgrade.Chapter 8 Overview of Austroads 2004 Features 75 Project Reliability The Project Reliability is defined as follows (Austroads 2004): The Project Reliability is the probability that the pavement when constructed to the chosen design will outlast its Design Traffic before major rehabilitation is required. whereas with Austroads 1992.5 Highway: lane AADT>2.97. b The vertical Elastic modulus of the top sub-layer is the minimum of the value specified in the CIRCLY input (indicative values are given in Table 6. The desired project reliability is chosen by the designer. a project is defined as a portion from a uniformly desig ned and (nominally) uniformly constructed road pavement which is subsequently rehabilita ted as an entity. the number of sub-layers were dependent on the thickness and elastic properties of t he layers.5 95 95 .000 90 Highway: lane AADT<2. In regard to these reliability procedures.3 of Austroads 2004) an d that determined using: 2(total granular thickness / 125) =× EV top sublayer EV subgrade 97. Typical project relia bility levels are given as follows (Austroads 2004): Project Reliability (%) Freeway 95 .90 . The procedure is: a Divide the total depth of unbound granular materials into 5 equi-thick sub-lay ers. Austroads 2004 always uses 5 equi-thick sub-layers. CIRCLY 5.. E .0 User's Guide c The ratio of Elastic moduli of adjacent sub-layers is given by: 1 . combined) thickness of all selected materials is divided into fi ve sub-layers and each assigned an Elastic modulus value according to the following guidelines: a Divide the total depth of all selected subgrade materials into 5 equi-thick su b-layers. d The Elastic modulus of each sub-layer may then be calculated from the Elastic modulus of the adjacent underlying sub-layer.. 5 R = . top granular sublayer E subgrade . Selected Subgrade Materials Selected subgrade materials are a special case of unbound granular material. The vertical Elastic modulus of the top sub-layer of selected subgrade is the mi nimum of 10 times the design CBR of the selected subgrade material and that determined us ing: . beginning with the subgrade or upper sub-l ayer of selected subgrade material as appropriate.e. The total (i. the Elastic modulus of which is kn own. . beginning with the insitu subgrade. the El astic modulus of which is known.× 2 (total selectedsubgrade thickness /150) E = E V top sublayer V insitu subgrade b The ratio of Elastic moduli of adjacent sub-layers is given by: 1 . a c heck needs to be made that the vertical Elastic modulus calculated for each sub-layer (step . 5 top selectedsubgradesublayer R ... . d If the pavement includes more than one type of selected subgrade material. = E insitu subgrade c The Elastic modulus of each sub-layer may then be calculated from the Elastic modulus of the adjacent underlying sub-layer. E .. an alternative trial selecte d subgrade configuration needs to be selected. Performance Models The main change to the Performance Models is the introduction of a Reliability F actor. If this condition is not met. k . .. e . .. b N = RF . RF.a) does not exceed 10 times the design CBR of each selected subgrade material within the sub-layer. µe Note that a Reliability Factor is not used for the subgrade.0 1.7 3.0 1.Chapter 8 Overview of Austroads 2004 Features The Performance models for Cemented and Asphalt Materials are the same as for Au stroads 1992.67 Subgrade The subgrade Performance Model used in Austroads 2004 is: 7 . Cemented Materials Suggested Reliability Factors (RF) for Cemented Materials Fatigue (Austroads 200 4) 97.5% Reliability Factor (RF) 2..5% Reliability Factor (RF) 4. N .3 2. apart from the introduction of the Reliability Factor.5 Asphalt Suggested Reliability Factors (RF) for Asphalt Fatigue (Austroads 2004) 97.5 2.0 0.5 1. .0 0. = . 9300 .. How to Use New Austroads 2004 Features The previous Section provided an Overview of the new features in the Austroads 2 004 Guide. This Section shows how to use the new Austroads features in CIRCLY 5.0. The following notes assume that you are already familiar with using CIRCLY 4.0 o r 4.1 in conjunction with the original Guide. Modelling the Standard Axle The layout of the four wheels used to model the Standard Axle is shown in the ea rlier section (see "Model of Standard Axle" on page 74). The design tyre pressure for pavement analysis is taken as 750 kPa (Chapter 7, A ustroads 2004). This Standard Axle is provided in the Load Groups database with the ID given by "ESA75Full". CIRCLY 5.0 User's Guide How to Use Project Reliability Click on the button. This will bring up the following screen: 1 1 Click the Reliability tab to switch to the Reliability form. This will bring u p the following form: 2 Chapter 8 How to Use New Austroads 2004 Features 2 Click on Use Project Reliability Factors. 3 In the Project Reliability list, click the desired Project Reliability. 3 4 4 This Table shows the Reliability Factor for each Material Type. Changes to Materials The Materials database in CIRCLY is affected by the Austroads 2004 changes in th ree main areas: 1 Unbound Granular Materials 2 Subgrade Materials CIRCLY 5.0 User's Guide 3 Select Subgrade Materials To ensure that pavements can be handled using either the Austroads 1992 or Austr oads 2004 methods, separate Material Types are used for variants of these materials: Austroads 2004 Unbound Granular Material Unbound Granular (Austroads 1992 sub-layering) Unbound Granular (Austroads 2004 sub-layering) Subgrade Subgrade (Austroads 1992) Subgrade (Austroads 2004) Select Subgrade Material n/a Subgrade (Selected Material) n/a = not applicable Austroads 2004 Examples Appendix 8.3 (Austroads 2004) outlines three worked examples that apply a mechan istic design procedure for flexible road pavements. Copies of these examples are provided in the CIRCLY database: Pavement Description Austroads 2004 - Example 1 - Unbound Granular Pavement Sprayed Seal Surfaced Unbound Granular Pavement Austroads 2004 - Example 2- Asphalt Pavement with CT Subbase Asphalt Pavement containing a Cemented Material Subbase (pre-cracking phase) Austroads 2004 - Example 2- Asphalt Pavement with CT Subbase-Post-Cracked Asphalt Pavement containing a Cemented Material Subbase (post-cracking phase) Austroads 2004 - Example 3 - Full Depth Asphalt Pavement Full Depth Asphalt Pavement CT = Cement Treated See Appendix 8.3 (Austroads 2004) for full details of the parameters used. (Austroads: Sydney). Geomechanics Computer Program. (1977). Austroads Publication. (2004). Australia. L. Austroads Publication No. 2004 Austroads Pavement Design Guide.J. 2001 Austroads Pavement Design Guide (Final Draft). Wardle. Austroads Publication No. (Austroads: Sydney). Division of Ap plied Geomechanics. Wardle.J. No. L. Austroads (2001). Mincad Systems . . CSIRO Australia. (At the time of writing the publication number and date wer e not known). Program CIRCLY User s Manual. Austroads (2004). AP-T10/01. 2. AP-17/92. (Austroads: Sydney). Pavement Design A Guide to the Structural Design of Road Pavem ents.References Austroads (1992). Program CIRCLY Theory and Background Manual.