Designation: D 5878 – 05Standard Guides for Using Rock-Mass Classification Systems for Engineering Purposes1 This standard is issued under the fixed designation D 5878; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. 1. Scope* 1.6 This standard offers an organized collection of informa- 1.1 This standard offers the selection of a suitable system of tion or a series of options and does not recommend a specific classification of rock mass for specific engineering purposes, course of action. This document cannot replace education ore such as tunneling and shaft-sinking, excavation of rock cham- experience and should be used in conjunction with professional bers, ground support, modification and stabilization of rock judgement. Not all aspects of this standard may be applicable slopes, and preparation of foundations and abutments. These in all circumstances. This ASTM standard is not intended to classification systems may also be of use in work on rippability represent or replace the standard of care by which the of rock, quality of construction materials, and erosion resis- adequacy of a given professional service must be judged, nor tance. Although widely used classification systems are treated should this document be applied without consideration of a in this standard, systems not included here may be more project’s many unique aspects. The word “Standard” in the appropriate in some situations, and may be added to subse- title of this document means only that the document has been quent editions of this standard. approved through the ASTM consensus process. 1.2 The valid, effective use of this standard is contingent 2. Referenced Documents upon the prior complete definition of the engineering purposes to be served and on the complete and competent definition of 2.1 ASTM Standards: 3 the geology and hydrology of the engineering site. Further, the D 653 Terminology Relating to Soil, Rock, and Contained person or persons using this standard must have had field Fluids experience in studying rock-mass behavior. An appropriate D 3740 Practice for Minimum Requirements for Agencies reference for geological mapping in the underground is pro- Engaged in the Testing and/or Inspection of Soil and Rock vided by Guide D 4879. as Used in Engineering Design and Construction 1.3 This standard identifies the essential characteristics of D 4879 Guide for Geotechnical Mapping of Large Under- seven classification systems. It does not include detailed ground Openings in Rock guidance for application to all engineering purposes for which D 6026 Practice for Using Significant Digits in Geotechni- a particular system might be validly used. Detailed descriptions cal Data of the first five systems are presented in STP 984 (1),2 with D 6032 Test Method for Determining Rock Quality Desig- abundant references to source literature. Details of two other nation (RQD) of Rock Core classification systems and a listing of seven Japanese systems D 7012 Test Method for Compressive Strength and Elastic are also presented. Moduli of Intact Rock Core Specimens Under Varying 1.4 The range of applications of each of the systems has States of Stress and Temperatures grown since its inception. This standard summarizes the major 3. Terminology fields of application up to this time of each of the seven classification systems. 3.1 Definitions: 1.5 This standard does not purport to address all of the 3.1.1 classification, n—a systematic arrangement or divi- safety concerns, if any, associated with its use. It is the sion of materials, products, systems, or services into groups responsibility of the user of this standard to establish appro- based on similar characteristics such as origin, composition, priate safety and health practices and determine the applica- properties, or use (Regulations Governing ASTM Technical bility of regulatory limitations prior to use. Committees).4 1 3 This standard is under the jurisdiction of ASTM Committee D18 on Soil and For referenced ASTM standards, visit the ASTM website, www.astm.org, or Rock and is the direct responsibility of Subcommittee D18.12 on Rock Mechanics. contact ASTM Customer Service at
[email protected]. For Annual Book of ASTM Current edition approved Jan. 1, 2005. Published February 2005. Originally Standards volume information, refer to the standard’s Document Summary page on approved in 1995. Last previous edition approved in 2000 as D 5878 – 00. the ASTM website. 2 4 The boldface numbers given in parentheses refer to a list of references at the Available from ASTM Headquarters, 100 Barr Harbor Drive, West Consho- end of the text. hocken, PA 19428. *A Summary of Changes section appears at the end of this standard. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. 1 D 5878 – 05 3.1.2 rock mass (in situ rock), n—rock as it occurs in situ, extended into the construction phase by continued monitoring including both the rock material and its structural discontinui- of rock displacement. Support requirements are revised to ties (Modified after Terminology D 653 [ISRM]). achieve stability (6). 3.1.2.1 Discussion—Rock mass also includes at least some NOTE 2—The Austrian code (7) specifies methods of payment based on of the earth materials in mixed-ground and soft-ground condi- coding of excavation volume and means of support. tions. 3.1.3 rock material (intact rock, rock substance, rock ele- 4.1.7 The Coal Mine Roof Rating (CMRR)—This system ment), n—rock without structural discontinuities; rock on applies to bedded coal-measure rocks, in particular with regard which standardized laboratory property tests are run. to their structural competence as influenced by discontinuities 3.1.4 structural discontinuity (discontinuity), n—an inter- in the rock mass. The basic building blocks of CMRR are unit ruption or abrupt change in a rock’s structural properties, such ratings. The units are rock intervals defined by their geotech- as strength, stiffness, or density, usually occurring across nical properties, and are at least 0.15 m (6 in.) thick. The unit internal surfaces or zones, such as bedding, parting, cracks, ratings are combined into roof ratings, using additional geo- joints, faults, or cleavage. technical characteristics (8). 4.1.8 Japanese Rock Mass Classification Systems—The NOTE 1—To some extent, 3.1.1, 3.1.2, and 3.1.4 are scale-related. A Japanese Society of Engineering Geology has recognized rock’s microfractures might be structural discontinuities to a petrologist, but to a field geologist the same rock could be considered intact. Similarly, seven major classification systems in use in Japan (9). These the localized occurrence of jointed rock (rock mass) could be inconse- are summarized in 4.1.8.1-4.1.8.7, without additional details in quential in regional analysis. this guide. 4.1.8.1 Rock-Mass Classification for Railway Tunnels by 3.1.5 For the definition of other terms that appear in this Railway Technical Research Institute—Rock-masses are clas- standard, refer to STP 984, Guide D 4879, and Terminology sified based on the values of P-wave velocity, unconfined D 653. compressive strength and unit weight. Support patterns for 3.2 Definitions of Terms Specific to This Standard: tunnels, such as shotcreting and rock bolting, is recommended 3.2.1 classification system, n—a group or hierarchy of depending upon the rock-mass classification obtained. classifications used in combination for a designated purpose, 4.1.8.2 Rock-Mass Classification for Tunnels and Slopes by such as evaluating or rating a property or other characteristic of Japan Highway Public Corporation—This system classifies a rock mass. the rock-mass using RQD, P-wave velocity, unconfined com- pressive strength and unit weight. 4. Significance and Use 4.1.8.3 Rock-Mass Classification for Dam Foundations by 4.1 The classification systems included in this standard and Public Works Research Institute, Ministry of Construction—In their respective applications are as follows: this system, the rock-masses are classified by observing spac- 4.1.1 Rock Mass Rating System (RMR) or Geomechanics ing of joints, conditions of joints and strength of rock pieces. Classification—This system has been applied to tunneling, 4.1.8.4 Rock-Mass Classification for Water Tunnel Design hard-rock mining, coal mining, stability of rock slopes, rock by The Ministry of Agriculture, Forestry and Fisheries—The foundations, borability, rippability, dredgability, weatherability, rock-mass is classified into four categories based on values of and rock bolting. P-wave velocity, compressive strength and Poisson ratio as 4.1.2 Rock Structure Rating System (RSR)—This system has well as rock type. been used in tunnel support and excavation and in other ground 4.1.8.5 Rock-Mass Classification by Central Research Insti- support work in mining and construction. tute of Electric Power Industry—This system classifies rock- 4.1.3 The Q System or Norwegian Geotechnical Institute mass based on rock type and weathering characteristics. System (NGI)—This system has been applied to work on 4.1.8.6 Rock-Mass Classification by Electric-Power Devel- tunnels and chambers, rippability, excavatability, hydraulic opment Company—This system is somewhat similar to the erodibility, and seismic stability of roof-rock. system developed by the Central Research Institute of Electric 4.1.4 The Unified Rock Classification System (URCS)— Power Industry (see 4.1.8.5). The three factors used for This system has been applied to work on foundations, methods classifying rock-mass are weathering, hardness and joint spac- of excavation, slope stability, uses of earth materials, blasting ing. characteristics of earth materials, and transmission of ground 4.1.8.7 Rock-Mass Classification for Weathered Granite for water. Bridge Foundation by Honshu-Shikoku Bridge Authority— 4.1.5 The Rock Material Field Classification System This system uses results of visual observations of rock-mass in (RMFCS)—This system has been used mainly for applications situ, geophysical logging, laboratory tests on rock samples, involving shallow excavation, particularly with regard to pressuremeter tests or other forms of in-situ tests or a combi- hydraulic erodibility in earth spillways, excavatability, con- nation thereof, to estimate strength and stiffness. struction quality of rock, fluid transmission, and rock-mass 4.2 Other classification systems are described in detail in the stability (11). general references listed in the appendix. 4.1.6 The New Austrian Tunneling Method (NATM)—This 4.3 Using this standard, the classifier should be able to system is used for both conventional (cyclical, such as drill- decide which system appears to be most appropriate for the and-blast) and continuous (tunnel-boring machine or TBM) specified engineering purpose at hand. The next step should be tunneling. This is a tunneling procedure in which design is the study of the source literature on the selected classification 2 D 5878 – 05 system and on case histories documenting the application of Unit weight that system to real-world situations and the degree of success Color of each such application. Appropriate but by no means exhaus- Rock Mass Properties tive references for this purpose are provided in the appendix Discontinuity type and in STP 984 (1). The classifier should realize that taking the Joint set spacing step of consulting the source literature might lead to abandon- Joint persistence ment of the initially selected classification system and selection Aperture of another system, to be followed again by study of the Joint count number appropriate source literature. Joint wall roughness NOTE 3—The quality of the results produced by this standard is Joint infilling dependent on the competence of the personnel performing it, and the Type of large geomorphic or structural feature suitability of the equipment and facilities used. Agencies that meet the Seismic velocity criteria of Practice D 3740 are generally considered capable of competent Rock quality designation (RQD) (see D 6032) and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself ensure Geohydraulic Properties reliable results. Reliable results depend on many factors. Practice D 3740 Primary porosity provides a means for evaluating some of these factors. Secondary porosity Hydraulic conductivity 5. Basis for Classification Transmissivity 5.1 The parameters used in each classification system fol- Storativity low. In general, the terminology used by the respective author Water table/potentiometric surface or authors of each system is listed, to facilitate reference to Aquifier type STP 984 (1) or source documents. 5.1.6 New Austrian Tunneling Method (NATM) 5.1.1 Rock Mass Rating System (RMR) or Geomechanics A:1.Stable Classification 2.Overbreaking Uniaxial compressive strength (see D 7012, Method C) B:1.Friable Rock quality designation (RQD) (see D 6032) 2.Very friable Spacing of discontinuities 3.Rolling/running Condition of discontinuities C:1.Rock bursting Ground water conditions 2.Squeezing Orientation of discontinuities 3.Heavily squeezing 5.1.2 Rock Structure Rating System (RSR) 4.Flowing Rock type plus rock strength 5.Swelling Geologic structure 5.1.7 Coal Mine Roof Rating (CMRR) Spacing of joints Unit Ratings Orientation of joints Shear strength of discontinuities Weathering of joints Cohesion Ground water inflow Roughness 5.1.3 Q-System or Norwegian Geotechnical Institute (NGI) System Intensity of discontinuities Rock quality designation (RQD) (see D 6032) Spacing Number of joint sets Persistence Joint roughness Number of discontinuity sets Joint alteration Compressive strength Joint water-reduction factor Moisture sensitivity Stress-reduction factor Roof Ratings 5.1.4 Unified Rock Classification System (URCS) Strong bed adjustment Degree of weathering Unit contact adjustment Uniaxial compressive strength (see D 7012, Method C) Groundwater adjustment Discontinuities Surcharge adjustment Unit weight 5.2 Comparison of parameters among these systems indi- 5.1.5 Rock Material Field Classification System (RMFCS) cates some strong similarities. It is not surprising, therefore, Rock Material Properties that paired correlations have been established between RMR, Principal rock type RSR, and Q (2). Some of the references in the appendix also Mineralogy present procedures for estimating some in situ engineering Primary porosity, voids properties from one or more of these indexes (2, 3, 4, and 5). Discrete rock particle size NOTE 4—Reference (2) presents step-by-step procedures for calculating Hardness and applying RSR, RMR, and Q values. Applications of the first five Unconfined composite strength (see D 7012, Method C) systems are discussed in STP 984 (1), as is a detailed treatment of RQD. 3 rock quality designation 6. 7.1 The annex of this standard contains tabled and other Excavation class matrix for conventional tunneling (The material for determining the parameters needed to apply each excavation class matrix for continuous (TBM) tunneling is of the classification systems. Adjustments for mining applications 6. such as uniaxial Classification Elements—Including rock material properties. An active span is the largest unsupported span between the face Effect of discontinuity strike and dip in tunneling and artificial supports (10).6 Guide F—NATM (RQD). unified rock Rock mass types classification system (URCS) 4 . 6. These materials should be used in determined by standup time and the support factor. Ja Unit contacts adjustment Joint water reduction factor. classification system. JW Groundwater adjustment Stress reduction factor SRF Surcharge adjustment CMRR values ~Q 5 ~RQD/Jn! 3 ~Jr/Ja! 3 ~JW/SRF! (2) 6. Jn Roof rating calculation sheet Joint roughness number. rock Fluid Transmission mass.2 Guide B—RSR System Immersion test Schematic of the six parameters Field data sheet Rock type plus strength.) Classification parameters (five) and their ratings Support elements and rating factors (Sum ratings) NOTE 5—Standup time is the length of time following excavation that Rating adjustment for discontinuity orientations (Parameter an active span in an underground opening will stand without artificial No. or recorded in this standard is not directly related to Discontinuities (A–E) the accuracy with which the data can be applied in design or Unit weight (A–E) other uses. coal mine roof rat- Excavation Characteristics ing (CMRR). rock structure rating system (RSR). rock mass properties. geologic structure (“A”) Directions for field data sheet Joint spacing and orientation (“B”) Cohesion-roughness rating Weathering of joints and ground water inflow (“C”) Spacing-persistence rating ~RSR 5 A 1 B 1 C! (1) Multiple discontinuity set adjustment Strength rating 6. Japanese rock mass classification systems.5 Guide E—RMFCS Schematic of procedure through performance assessment 7. new Construction Quality Austrian tunneling method (NATM). Precision Classification (description and definitions). Keywords Hydraulic Erodibility in Earth Spillways 8.1 Guide A—RMR System rating factors are assigned.4 Guide D—URCS Practice D 6026.1.1.1. D 5878 – 05 6. Degree of weathering (A–E) 6. 6) (RMR = adjusted sum) support. rock mass rating system (RMR).1 classification. the latter conjunction with detailed. Estimated strength (A–E) calculated.3 Guide C—Q-System: Moisture sensitivity rating RQD Unit rating calculation sheet Joint set number.2 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in 6. Jr Strong bed adjustment Joint alteration number. Performance Assessment—Performance objectives 8. and hydrogeologic properties.1.7 Guide G—CMRR Input data CMRR calculation 6.1 The method used to specify how data are collected. 984 (1) and Ref (2). The annexed materials are as follows: although there may be some differences in the way in which 6. compressive strength and rock quality designation. rock material field Rock Mass Stability classification system (RMFCS). instructive references such as STP calculated in the same way as for conventional tunneling.1.1.2. Procedures for Determining Parameters Calculation of support factor 6.1 Precision statements will be available for some compo- Rock unit nents of some of the classification systems. Q-system (NGI). How one applies the results obtained using Schematic of notation (results = AAAA through EEEE) this standard is beyond its scope. or both.1. Rapid Boca Raton. pp. and their Effect on Contracting Practices. 1994. Institution of Mining and Metallurgy. pp. The materials for CMRR are from Ref.. (2) Bieniawski. 335–344. “Uniform Rock Classification for Geo- Rock”.“ NATM Ground Support Concepts cation Systems and Modes of Ground Failure. G. Wickham. 984. 2. T. H.1 The materials presented in this Annex for RMR. 1989. Fairhurst. Sect. A. E. DC. pp.. Vol 12. (8) Molinda. 1992. (11) Natural Resources Conservation Service. New York.” Proceedings.. H. Lien. Z. ASTM STP Response. G.. Pittsburgh. technical Engineering Purposes.” Felsbau. 1994. Z.. Sauer. pp. REFERENCES (1) Rock Classification Systems for Engineering Purposes.. Jr. A... E. June Bell. and Skinner. Interscience. “Engineering Classification of Circular 9387. in Failure and Breakage of Rock. The materials for NATM are from Ref. Washington.” Japanese Society of Engineering (4) Barton. No. Practical Rock Mass Classification for Coal Mines. National Academy of Sciences. (5) Bieniawski. 1989. RSR Concept. 9–14. Tiedemann. and Cording. A. Deere. “The Q-System Following Twenty Geology. A. Engineering Rock Mass Classifications. T. and Grimstad. 6.. Second Rapid Excavation and Tunneling Confer- Civil Engineers. J. Excavation and Tunneling Conference. C. F. ASTM. and Lunde.” Rock Mechanics. N. 3. E. G. E.” in Pro- Rock Masses”. 1992. Chapt. RSR. H. Engineering Properties of Soils and Rocks.. J. F. of Agriculture. “Engineering Classification of Jointed “Ground Support Prediction Model. 179–182. Rock Mechanics Design in Mining and Tunneling. (9) “Rock Mass Classification in Japan. p. Vol 6. 1988. G. 189–236. Underground Excavations in Rock. New York. T.” Information (3) Barton. and URCS have been extracted from STP 984 (1). No. 67–86. D. CRC Press. 4. E.S. “Coal Mine Roof Rating (CMRR): A Balkema. 2002. R. 1984.. “Classification of Earth (Geologic) Material... Rock Masses for the Design of Tunnel Support... Oxford.” Felsbau. R. Practical Handbook of Rock Mass Classifi. Vol 15. “Design of Surface and Near-Surface Construction in Williamson. 1992. Ch. M. Part 631. No. 1997. ON B2203/1994. E.. N.. San Francisco.. The materials for RMFCS are from Ref. Z.. 691–707. Bieniawski. Ed. 5. Vol I. 1967. H. 12. Patton. ence. Bureau of Mines.. CLASSIFICATION SYSTEM MATERIAL A1. Wiley. (11). and Brown. 1980. Vol 15. Years of Application in NMT Support Selection. Dept. U. and Mark. J. 1980. Rotterdam. PA. pp. 237–302. The materials for Q (NGI) are from Ref (4). (8). ˝ (7) Austrian Code. Butterworth-Heinemann.. APPENDIX (Nonmandatory Information) X1. Los Angeles.” Transportation Research Society of Mining Engineers of AIME.” National Engineering (6) Lauffer. A. D. U. A. 428–436. T. 1973. pp. 1974. C. June 1974. Record 783. (6). pp... U.. (10) Hoek. and Gold. D.16. D 5878 – 05 ANNEX (Mandatory Information) A1. 5 ... “Rock Classification Methods Based on the Excavation Handbook.S. Hendron. London.. ADDITIONAL INFORMATION Afrouz. Transactions of the South African Institution of ceedings. pp. that is. systems. immediately following the seven procedures in the standard. is replaced by generation RMFCS.” illustrations. are as follows: (1) Title is expressed in the plural. and designations Guide A-G are given to these and immediately preceding the section on precision. three pages of ap- (2) References to and/or notes from D 3740. D 6026. requiring changes throughout in the text. D 5878 – 00.” in place of Section 1 (Scope) because the former is where this belongs “Guide. “standard. In addition. the term (3) The RMFC procedure has been replaced by the next- “guide. “Guides. and references.” where it refers to the whole standard.” to reflect the inclusion of seven classification systems logically. rather than in 6 . placed at the end of Section 6 (Procedures). and pended materials in the 2000 edition have been replaced by five D 6032 have been added. The text relating to D 6026 has been tables. D 5878 – 05 SUMMARY OF CHANGES The principal changes to this guide that have been incorporated since the last issue. Consistent with this and to avoid confusion. D 5878 – 05 7 . D 5878 – 05 8 . D 5878 – 05 9 . D 5878 – 05 10 . D 5878 – 05 11 . D 5878 – 05 12 . D 5878 – 05 13 . D 5878 – 05 14 . D 5878 – 05 15 . D 5878 – 05 16 . D 5878 – 05 17 . D 5878 – 05 18 . D 5878 – 05 19 . D 5878 – 05 20 . D 5878 – 05 21 . D 5878 – 05 22 . D 5878 – 05 23 . D 5878 – 05 24 . D 5878 – 05 25 . D 5878 – 05 26 . D 5878 – 05 27 . D 5878 – 05 28 . D 5878 – 05 29 . or through the ASTM website (www. which you may attend. at the address shown below. either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610-832-9585 (phone). 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