ASTM_D_6467_-_13.pdf

Designation:D646713Standard Test Method forTorsional Ring Shear Test to Determine Drained ResidualShear Strength of Cohesive Soils1This standard is issued under the fixed designation D6467;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method provides a procedure for performing atorsional ring shear test under a drained condition to determinethe residual shear strength of cohesive soils.An intact speci-men can be used for testing.However,obtaining a natural slipsurface specimen,determining the direction of field shearing,and trimming and aligning the usually non-horizontal shearsurface in the ring shear apparatus is difficult.As a result,thistest method focuses on the use of a reconstituted specimen tomeasure the residual strength.This test method is performed bydeforming a presheared,reconstituted specimen at a controlleddisplacement rate until the constant drained shear resistance isoffered on a single shear plane determined by the configurationof the apparatus.An unlimited amount of continuous sheardisplacement can be achieved to obtain a residual strengthcondition.Generally,three or more normal stresses are appliedto a test specimen to determine the drained residual failureenvelope.A separate test specimen may be used for eachnormal stress.1.2 A shear stress-displacement relationship may be ob-tained from this test method.However,a shear stress-strainrelationship or any associated quantity,such as modulus,cannot be determined from this test method because soilextrusion and volume change prevents defining the heightneeded in the shear strain calculations.As a result,shear straincannot be calculated but shear displacement can be calculated.1.3 The selection of normal stresses and determination ofthe shear strength envelope for design analyses and the criteriato interpret and evaluate the test results are the responsibility ofthe engineer or office requesting the test.1.4 The values stated in SI units are to be regarded asstandard.The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.5 All measured and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D422 Test Method for Particle-Size Analysis of SoilsD653 Terminology Relating to Soil,Rock,and ContainedFluidsD854 Test Methods for Specific Gravity of Soil Solids byWater PycnometerD2216 Test Methods for Laboratory Determination of Water(Moisture)Content of Soil and Rock by MassD2435 Test Methods for One-Dimensional ConsolidationProperties of Soils Using Incremental LoadingD2487 Practice for Classification of Soils for EngineeringPurposes(Unified Soil Classification System)D3080 Test Method for Direct Shear Test of Soils UnderConsolidated Drained ConditionsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4318 Test Methods for Liquid Limit,Plastic Limit,andPlasticity Index of SoilsD6026 Practice for Using Significant Digits in GeotechnicalData3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.05 on Strength andCompressibility of Soils.Current edition approved May 1,2013.Published July 2013.Originally approvedin 1999.Last previous edition approved in 2006 as D6467 06a.DOI:10.1520/D6467-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.1 consolidatedsoil specimen condition after primaryconsolidation under a specific normal stress.3.2.2 preshearedsoil specimen condition after shearing toat least one revolution of the ring in the direction of shear tocreate a failure surface prior to drained shearing.3.2.3 residual shear forcethe shear force is the averageforce being applied to the specimen when the shear resistanceneither increa