Designation:C1851−18StandardPracticeforDeterminingtheExtentofCrackinginaSealantusingtheDifferencebetweentheCompressiveandTensileModulus1ThisstandardisissuedunderthefixeddesignationC1851;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoversaprocedureforquantitativelydeterminingtheextentofcrackinginasealantsamplebyevaluatingthedifferencebetweenthemeasuredcompressiveandtensilemodulusofasealantrelativetoanunexposedoruncrackedversionofthesamesealant.Thecrackswillreducetheareaofthesealantinthetensilemodulus,butinthecompressivemodulusmeasurementtheywillnotchangetheareaoverwhichthemodulusisdetermined.1.2ThevaluesinSIunitsaretoberegardedasstandard.Thevaluesinparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2C717TerminologyofBuildingSealsandSealantsC719TestMethodforAdhesionandCohesionofElasto-mericJointSealantsUnderCyclicMovement(HockmanCycle)C1735TestMethodforMeasuringtheTimeDependentModulusofSealantsUsingStressRelaxationE631TerminologyofBuildingConstructions3.Terminology3.1Definitions:3.1.1Fordefinitionsoftermsusedinthispractice,refertoTerminologiesE631andC717.4.SummaryofPractice4.1ThispracticeconsistsofmeasuringthemodulusofthesealantusingTestMethodC1735inbothtensionandcompres-sion.Oncethe...
