Designation:D7956/D7956M−14StandardPracticeforCompressiveTestingofThinDamagedLaminatesUsingaSandwichLongBeamFixtureSpecimen1ThisstandardisissuedunderthefixeddesignationD7956/D7956M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoversanapproachforcompressivetest-ingthindamagedmultidirectionalpolymermatrixcompositelaminatesreinforcedbyhigh-modulusfibersusingasandwichlongbeamflexurespecimen.Itprovidesatestconfigurationinwhichthecoredoesnotconstrainanyprotrudingbacksidedamage.Itislimitedtotestingofmonolithicsolidlaminateswhicharetoothintobetestedusingtypicalanti-bucklingfixtures.Itdoesnotcovercompressivetestingofdamagedsandwichpanelfacings.Thecompositematerialformsarelimitedtocontinuous-fiberordiscontinuous-fiber(tapeorfabric,orboth)reinforcedcompositesinwhichthelaminateisbalancedandsymmetricwithrespecttothetestdirection1.2ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.2.1Withinthetexttheinch-poundunitsareshowninbrackets.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2C274TerminologyofStructuralSandwichConstructionsD883TerminologyRelatingtoPlasticsD3878TerminologyforCompositeMaterialsD3410TestMethodforCompressivePropertiesofPolymerMatrixCompositeMaterialswithUnsupportedGageSec-tionbyShearLoadingD6264/D6264MTestMethodforMeasuringtheDamageResistanceofaFiber-ReinforcedPolymer-MatrixCom-positetoaCo...
