Designation:D7625−10StandardTestMethodforLaboratoryDeterminationofAbrasivenessofRockUsingtheCERCHARMethod1ThisstandardisissuedunderthefixeddesignationD7625;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoftheabra-sivenessofrockbytheCERCHARAbrasivenessIndex(CAI)method.ThetestmethodconsistsofmeasuringthewearonthetipofsteelstyluswithaconeshapeandknownRockwellHardness,causedbyscratchingagainstafreshlybrokenorsawcutrocksurfaceforaprescribed10mmdistanceusingoneofthetwotestapparatus.1.2Thistestmethodisintendedforfreshlybrokenrocksurfaces;however,sawcutsurfacesarecoveredforwhenasatisfactoryrocksurfacecannotbeobtained.1.3StylusRockwellHardness(HRC)canhaveaprofoundeffectontheresultsandthefocusofthistestmethodisanHRCvalueof55foreverytest(1,2).2However,therearesituationswherestyluswithdifferentRockwellHardnesscanbeusedTherefore,thistestmethodincludesdiscussionsonstyluswithdifferentRockwellHardness.1.4AllobservedandcalculatedvaluesshallconformtotheguidelinesforsignificantdigitsandroundingestablishedinPracticeD6026.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3D653TerminologyRelatingtoSoil,Rock,andContainedFluidsD2216TestMethodsforLaboratoryDeterminationofWater(Moisture)ContentofSoilandRockbyMassD3740PracticeforMinimumRequirementsforAgenciesEngagedinTestingand/orInspectionofSoilandRockasUsedinEngineeringDesignandConstructionD5079PracticesforPreservingandTransportingRockCoreSamplesD6026Practic...
