ASTM_D_6243_-_D_6243M_-_13a.pdf

Designation:D6243/D6243M13aStandard Test Method forDetermining the Internal and Interface Shear Strength ofGeosynthetic Clay Liner by the Direct Shear Method1This standard is issued under the fixed designation D6243/D6243M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers a procedure for determining theinternal shear resistance of a Geosynthetic Clay Liner(GCL)orthe interface shear resistance between the GCL and an adjacentmaterial under a constant rate of deformation.1.2 This test method is intended to indicate the performanceof the selected specimen by attempting to model certain fieldconditions.1.3 This test method is applicable to all GCLs.Remolded orundisturbed soil samples can be used in the test device.SeeTest Method D5321 for non-GCLs.1.4 This test method is not suited for the development ofexact stress-strain relationships within the test specimen due tothe nonuniform distribution of shearing forces and displace-ment.1.5 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.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:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD698 Test Methods for Laboratory Compaction Character-istics of Soil Using Standard Effort(12 400 ft-lbf/ft3(600kN-m/m3)D1557 Test Methods for Laboratory Compaction Character-istics of Soil Using Modified Effort(56,000 ft-lbf/ft3(2,700 kN-m/m3)D2435/D2435M Test Methods for One-Dimensional Con-solidation Properties of Soils Using Incremental LoadingD2487 Practice for Classification of Soils for EngineeringPurposes(Unified Soil Classification System)D3080/D3080M Test Method for Direct Shear Test of SoilsUnder Consolidated Drained ConditionsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4439 Terminology for GeosyntheticsD5321 Test Method for Determining the Shear Strength ofSoil-Geosynthetic and Geosynthetic-Geosynthetic Inter-faces by Direct ShearD6072/D6072M Practice for Obtaining Samples of Geosyn-thetic Clay Liners3.Terminology3.1 DefinitionsFor definitions of terms relating to soil androck,refer to Terminology D653.For definitions of termsrelating to GCLs,refer to Terminology D4439.3.2 Definitions of Terms Specific to This Standard:3.2.1 adhesion,ca,nthe y-intercept of the Mohr-Coulombstrength envelope.3.2.2 atmosphere for testing geosynthetics,nair main-tained at a relative humidity of between 50 and 70%andtemperature of 21 6 2C 70 6 4F.3.2.3 GCL,na manufactured hydraulic barrier consistingof clay bonded to a layer,or layers,of geosynthetic materials.3.2.4 Mohr-Coulomb friction angle,n(angle of frictionof a material or between two materials,degrees)the angledefined by the least-squares,“best-fit”straight line through adefined section of the shear strength-normal stress failureenvelope;the component of the shear strength indicated by theterm,in Coulombs equation,=Ca+n*tan()(see 12.6).3.2.4.1 DiscussionThe end user is cautioned that some1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.04 on Geosyn-thetic Clay Liners.Current edition approved July 1,2013.Published August 2013.Originallyapproved in 1998.Last previous edition approved in 2013 as D624313.DOI:10.1520/D6243_D6243M-13A.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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 organizations(for example,FHWA,AASHTO along with stateagencies who use these documents)are currently using theGreek letter,Delta(),to designate wall-backfill interfacefriction angle and the Greek letter,Rho(),to designate theinterface friction angle between geosynthetics and soil.3,43.2.5 Mohr-Coulomb shear strength envelope,n(angle offriction between two materials)(degrees)the angle whosetangent is the slope of the line relating limiting value of theshear stress that resists slippage between two solid bodies andthe normal stress across