ASTM-C273-C273M-REV-A-2007

Designation:C273/C273M–07aStandardTestMethodforShearPropertiesofSandwichCoreMaterials1ThisstandardisissuedunderthefixeddesignationC273/C273M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thistestmethodcoversthedeterminationofshearpropertiesofsandwichconstructioncorematerialsassociatedwithsheardistortionofplanesparalleltothefacings.Itcoversthedeterminationofshearstrengthparalleltotheplaneofthesandwich,andtheshearmodulusassociatedwithstrainsinaplanenormaltothefacings.Thetestmaybeconductedoncorematerialsbondeddirectlytotheloadingplatesorthesandwichfacingsbondedtotheplates.Permissiblecorematerialformsincludethosewithcontinuousbondingsurfaces(suchasbalsawoodandfoams)aswellasthosewithdiscontinuousbondingsurfaces(suchashoneycomb).1.2ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Withinthetexttheinch-poundunitsareshowninbrackets.Thevaluesstatedineachsystemarenotexactequivalents;therefore,eachsystemmustbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnonconformancewiththestandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2C271/C271MTestMethodforDensityofCoreSandwichMaterialsC274TerminologyofStructuralSandwichConstructionsC393TestMethodforFlexuralPropertiesofSandwichConstructionsD792TestMethodsforDensityandSpecificGravity(Rela-tiveDensity)ofPlasticsbyDisplacementD883TerminologyRelatingtoPlasticsD2584TestMethodforIgnitionLossofCuredReinforcedResinsD2734TestMethodsforVoidContentofReinforcedPlas-ticsD3171TestMethodsforConstituentContentofCompositeMaterialsD3878TerminologyforCompositeMaterialsD5229/D5229MTestMethodforMoistureAbsorptionPropertiesandEquilibriumConditioningofPolymerMa-trixCompositeMaterialsD5687/D5687MGuideforPreparationofFlatCompositePanelswithProcessingGuidelinesforSpecimenPrepara-tionD5961/D5961MTestMethodforBearingResponseofPolymerMatrixCompositeLaminatesE4PracticesforForceVerificationofTestingMachinesE6TerminologyRelatingtoMethodsofMechanicalTest-ingE122PracticeforCalculatingSampleSizetoEstimate,WithaSpecifiedTolerableError,theAverageforaCharacteristicofaLotorProcessE177PracticeforUseoftheTermsPrecisionandBiasinASTMTestMethodsE456TerminologyRelatingtoQualityandStatisticsE1309GuideforIdentificationofFiber-ReinforcedPolymer-MatrixCompositeMaterialsinDatabasesE1434GuideforRecordingMechanicalTestDataofFiber-ReinforcedCompositeMaterialsinDatabasesE1471GuideforIdentificationofFibers,Fillers,andCoreMaterialsinComputerizedMaterialPropertyDatabases3.Terminology3.1Definitions—TerminologyD3878definestermsrelatingtohigh-modulusfibersandtheircomposites.TerminologyC274definestermsrelatingtostructuralsandwichconstruc-tions.TerminologyD883definestermsrelatingtoplastics.TerminologyE6definestermsrelatingtomechanicaltesting.TerminologyE456andPracticeE177definetermsrelatingtostatistics.Intheeventofaconflictbetweenterms,TerminologyD3878shallhaveprecedenceovertheotherterminologies.3.2Symbols:1ThistestmethodisunderthejurisdictionofASTMCommitteeD30onCompositeMaterialsandisthedirectresponsibilityofSubcommitteeD30.09onSandwichConstruction.CurrenteditionapprovedOct.1,2007.PublishedOctober2007.Originallyapprovedin1951.Lastpreviouseditionapprovedin2007asC273–07.2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.1Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.--``,,,`,,``,,,,```,,`,,```,``,`-`-`,,`,,`,`,,`---b=widthofspecimenCV=coefficientofvariationstatisticofasamplepopulationforagivenproperty(inpercent)G=coreshearmodulusL=lengthofspecimenP=forceonspecimenS=DP/Du,slopeofinitialportionofforce-deflectioncurveSn-1=standarddeviationstatisticofasamplepopulationforagivenpropertyt=thicknessofcoreu=displacementofloadingplatesx1=testresultforanindividualspecimenfromthesamplepopulationforagivenpropertyx=meanoraverage(estimateofmean)ofasamplepopulationforagivenpropertyg=coreengineeringshearstraint=coreshearstress4.SummaryofTestMethod4.1Thistestmethodconsistsofsubjectingasandwichcoreorsandwichpaneltomonotonicallyincreasingshearforceparalleltotheplaneofitsfaces.Theforceistransmittedtothespecimenthroughbondedloadingplatesthataresubjectedtoopposingtensileorcompressivedisplacementsthatresultinashearforceonthesandwichcore.Coreshearmodulus,stress,andstrengtharereportedintermsofthenominalshearareaofthecore.4.2Theonlyacceptablefailuremodeisshearfailureofthecorematerial.Adhesiveorcoh