Designation:D2922–05StandardTestMethodsforDensityofSoilandSoil-AggregateinPlacebyNuclearMethods(ShallowDepth)1ThisstandardisissuedunderthefixeddesignationD2922;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thesetestmethodscoverthedeterminationofthetotalorwetdensityofsoilandsoil-rockmixturesbytheattenuationofgammaradiationwherethesourceanddetector(s)remainonthesurface(BackscatterMethod)orthesourceordetectorisplacedataknowndepthupto300mm(12in.)whilethedetector(s)orsourceremainsonthesurface(DirectTransmis-sionMethod).1.2Thedensityinmassperunitvolumeofthematerialundertestisdeterminedbycomparingthedetectedrateofgammaradiationwithpreviouslyestablishedcalibrationdata.1.3ThevaluestestedinSIunitsaretoberegardedasthestandard.Theinch-poundequivalentsmaybeapproximate.1.4Itiscommonpracticeintheengineeringprofessiontoconcurrentlyusepoundstorepresentbothaunitofmass(lbm)andaunitofforce(lbf).Thisimplicitlycombinestwoseparatesystemsofunits;thatis,theabsolutesystemandthegravita-tionalsystem.Itisscientificallyundesirabletocombinetheuseoftwoseparatesetsofinch-poundunitswithinasinglestandard.Thesetestmethodshavebeenwrittenusingthegravitationalsystemofunitswhendealingwiththeinch-poundsystem.Inthissystemthepound(lbf)representsaunitofforce(weight).However,theuseofbalancesorscalesrecordingpoundsofmass(lbm),ortherecordingofdensityinlbm/ft3shouldnotberegardedasnonconformancewiththesetestmethods.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.ForspecificHazardstatements,seeSection6.2.ReferencedDocuments2.1ASTMStandard...
