Designation:D4645−08StandardTestMethodforDeterminationofIn-SituStressinRockUsingHydraulicFracturingMethod1ThisstandardisissuedunderthefixeddesignationD4645;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthedeterminationofthein-situstateofstressinrockbyhydraulicfracturing.NOTE1—Hydraulicfracturingforstressdeterminationisalsoreferredtoashydrofracturing,andsometimesasminifracing.Hydraulicfracturingandhydrofracturingmayalsorefertofracturingoftherockbyfluidpressureforthepurposeofalteringrockproperties,suchaspermeabilityandporosity.1.2Hydraulicfracturingisthewidelyacceptedfieldmethodavailableforinsitustressmeasurementsatdepthsgreaterthan50m.Itcanbeusedindrillholesofanydiameter.1.3Hydraulicfracturingcanalsobeusedinshortholesforwhichotherstressmeasuringmethods,suchasovercoring,arealsoavailable.Theadvantageofhydraulicfracturingisthatityieldsstressesaveragedoverafewsquaremetres(thesizeoftheinducedhydraulicfracture)ratherthanovergrainsizeareas,asinthecaseofovercoringtechniques.1.4AllobservedandcalculatedvaluesshallconformtotheguidelinesforsignificantdigitsandroundingestablishedinPracticeD6026.1.4.1Themethodusedtospecifiyhowdataarecollected,calculated,orrecordedinthisstandardisnotdirectlyrelatedtotheaccuracytowhichthedatacanbeappliedindesignorotheruses,orboth.Howoneappliestheresultsobtainedusingthisstandardisbeyonditsscope.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyproblems,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D653TerminologyRelatingtoSoil,Rock,a...
