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1、Designation:D1761?12StardTestMethodsfMechanicalFastenersinWood1ThisstardisissuedunderthefixeddesignationD1761thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecaseofrevisiontheyearoflastrevi

2、sion.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.ThisstardhasbeenapprovedfusebyagenciesoftheU.S.DepartmentofDefense.INTRODUCTIONTheuseofwoodw

3、oodbasematerialsinmanystructuralotherapplicationsofteninvolvestheuseofmechanicalfastenerssuchasnailsscrewsboltslagscrewsconnects.Dataonthestrengthperfmanceofsuchfastenersarefrequentlyneededfdesignfcomparativepurposes.Tes

4、tsofmechanicalfasteners(exceptnailwithdrawal)havebeengenerallyregardedasspecialtestshavenotbeenincludedinthestardmethodsalreadyestablishedfevaluatingthepropertiesofwood.Manysuchspecialtestshavebeenextensivelyusedoveracon

5、siderableperiodbuthavenotpreviouslybeenestablishedasstards.Presentedherewitharemethodsofconductingtestsfnailstaplescrew(exceptmachinescrews)withdrawalresistancelateralloadtransmissionbynailstaplescrewbolttimberconnectloa

6、dtransmissionbynailplates.Theuseofstardmethodsfthesetestsisrecommendedasameansofobtainingcomparabledataofeliminatingvariablesintestresultsbecauseofvariationsintestingmethods.Thetestsappearinthefollowingder:SectionsNailSt

7、apleScrewWithdrawalTest1to12LateralNailStapleScrewResistanceTest13to20TestingBoltedTimberConnectJoints21to30Keywds31NAILSTAPLESCREWWITHDRAWALTEST1.Scope1.1Thesetestmethodsprovideabasicprocedurefevaluatingtheresistanceofw

8、oodwoodbasematerialstodirectwithdrawalofnailsstaplesscrews.Spikesareincludedasnailsinthisstard.1.2Thetestsalsoprovideabasisfdeterminingcomparableperfmanceofdifferenttypessizesofnailsstaplesscrewsindirectwithdrawalfromwoo

9、dwoodbasematerials.1.3Thisstarddoesnotpurpttoaddressallofthesafetyproblemsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatyl

10、imitationspritouse.2.ReferencedDocuments2.1ASTMStards:2D143TestMethodsfSmallClearSpecimensofTimberD2395TestMethodsfDensitySpecificGravity(RelativeDensity)ofWoodWoodBasedMaterialsD4442TestMethodsfDirectMoistureContentMeas

11、urementofWoodWoodBasedMaterialsE4PracticesfFceVerificationofTestingMachines2.2OtherStards:FederalSpecificationFFW92fWashersMetalFlat(Plain)3ANSIB18.6.1AmericanNationalStardfSlotted1Thesetestmethodsareunderthejurisdiction

12、ofASTMCommitteeD07onWoodarethedirectresponsibilityofSubcommitteeD07.05onWoodAssemblies.CurrenteditionapprovedNov.12012.PublishedNovember2012.iginallyapprovedin1960.Lastpreviouseditionapprovedin2006asD1761–06.DOI:10.1520D

13、176112.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.3AvailablefromStardizationDocumentsderDesk

14、DODSSPBldg.4SectionD700RobbinsAve.PhiladelphiaPA191115098.Copyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates17.2Thetestsshouldbesufficientlyextensivetoprovidereliableresults.Wher

15、eanalysisbystatisticalproceduresiscontemplatedexperiencesometimesadvanceestimatescanbeusedtoestablishthescopeoftestingtypeofsamplingneededtoachievetheexpectedreliability.NOTE2—Theprecisionrequiredthusthemannerofsamplingn

16、umberoftestswilldependuponspecificobjectives.Nospecificcriteriatherefecanbeestablished.Generalexperienceindicatesthatthecoefficientofvariationfromtestsoffastenersrangesfromabout15to30%.Whensuchisthecaseprecisionof5to10%w

17、ith95%confidence(anoftenacceptedgeneralmeasureofreliabilityftestingwood)cannotbeachievedwithoutmakingaratherlargenumberoftests.Thepresentrecommendationistomakeatleast10replicationsfeachvariableasaminimumrequirement.8.Tes

18、tSpecimen8.1NailStapleWithdrawal:8.1.1Fbasicwithdrawaltestsfromwoodthewoodprismshallbe2by2by6in.(51by51by152mm).Nailsofthetypeoutlinedin6.1.1staplesofthetypeoutlinedin6.2.1shallbedrivenatrightanglestothefaceofthespecimen

19、toatotalperationof11?4in.(32mm).Twofastenersshallbedrivenintoatangentialsurfacetwointoaradialsurfaceoneintoeachend.Endedgedistancesshallbesufficienttoavoidsplitting.Ingeneraledgedistancesshouldnotbelessthan3?4in.(19mm)en

20、ddistancesnotlessthan11?2in.(38mm)twofastenersshallnotbedriveninlinewitheachotherlessthan2in.(51mm)apartonradialtangentialfaces.Nailsshallbedrivenmanuallywithahammer.Staplesshallbeedwithanappropriatetoolasnearlyaspossibl

21、eperpendiculartothespecimensurfacewiththestaplecrownata45(610)angletothegraindirectionoftheprism.8.1.2Fbasicwithdrawaltestsfromwoodproductsthetestprismshallbeasinglethicknessofconvenientsizenotsmallerthan3in.(76mm)wide6i

22、n.(152mm)long.Nailsofthetypeoutlinedin6.1.1staplesofthetypeoutlinedin6.2.1shallbedriventhroughthewoodproductatrightanglestothefacepermittingatleast1?2in.(13mm)oftheshankptiontoremainabovethesurface.Nailsshallbedrivenmanu

23、allybymeansofahammer.Staplesshallbeedwithanappropriatetoolasin8.1.1butifthereisnodiscerniblegraindirectioninthewoodproductthestaplecrownshallbeientedata45(610)angletothelengthoftheprism.8.1.3Fdeterminingthewithdrawalresi

24、stanceofparticularsizesshapesofnailsstaplesinwoodwoodproductsthespecimenshallbeofconvenientsizetoaccommodatethequantityoffastenerstobetestedineachspecimenwithoutexceedingtheedgeenddistancesspacingsnecessarytoavoidsplitti

25、ng.Inwoodfastenersshouldbedrivento70%oftheirlengthinthinpanelwoodproductstheyshouldbedrivencompletelythroughthethicknesswithatleast1?2in.(13mm)oftheshankptionremainingabovethesurface.Thefastenersshallbedrivenbythemethodi

26、ntendedtobeusedinpracticethatiseithermanuallywithahammerwithanapplicatappropriatetoolifthisisthenmalmethod.8.1.3.1Ifthewithdrawalresistancemaybeinfluencedbythematerialthroughwhichthefasteneristobedriventhefastenershallbe

27、driventhroughthefastenedmember(cleat)intothefasteningmember.8.2ScrewWithdrawal:8.2.1Fbasicwithdrawaltestsfromwoodthespecimenshallbe2in.(51mm)wide6in.(152mm)longwithdepthatleastequaltothelengthofthescrew.Twoscrewsofthetyp

28、eoutlinedin6.2.1shallbethreadedintoleadholesatrightanglestothetangentialfacetoatotalperationequaltothelengthofthethreadedption.Endedgedistanceshallbesufficienttoavoidsplittingwhichingeneralwillbeatleast3?4in.(19mm)fromth

29、eedge11?2in.(38mm)fromtheendspacingwillbeatleast21?2in.(63mm).Thesizeoftheleadholeshallbe70%oftherootdiameterofthescrewfsoftwoodshardwoodsshallextend1?2in.(13mm)intothefaceofthespecimen.Thescrewsmaybecoatedwithparaffinwa

30、xothersimilarlubricantwhennecessarytofacilitatedriving.8.2.2Fbasicwithdrawaltestsfromwoodproductsthespecimenshallbe3in.(76mm)inwidth6in.(152mm)inlength.Thedepthofthespecimenshallbeatleastequaltothelengthofthescrewitmaybe

31、necessarytogluetogethertwomethicknessesofmaterialtoprovidetherequireddepth.Screwsofthetypeoutlinedin6.2.1shallbethreadedintothespecimenadistanceof2?3in.(17mm)atwidthatleast2in.(51mm)fromtheendofthespecimen.Thesizeofleadh

32、oleshallbe70%oftherootdiameterofthescrewitshallextend1?2in.(13mm)intothefaceofthespecimen.Thescrewsmaybecoatedwithparaffinwaxothersimilarlubricantwhennecessarytofacilitatedriving.8.2.3Fdeterminingthewithdrawalresistanceo

33、fparticularsizestypesofscrewsinwoodwoodproductsthespecimenshallbeofconvenientsizetoaccommodatethequantityofscrewstobetestedineachspecimenwithoutexceedingtheedgeenddistancesspacingsnecessarytoavoidsplitting.Screwsshallbet

34、hreadedintothespecimenfthelengthofthethreadedptionoftheshanktwothirdsoftheshanklengthifitisthreadedthroughout.Thesizeofleadholeifoneistobedrilledshallbe70%oftherootdiameterofthescrewfadistanceofonehalfofthescrewlength.8.

35、2.3.1Ifthewithdrawalresistancemaybeinfluencedbythematerialthroughwhichthescrewistobethreadedthescrewshallbethreadedthroughaheldmemberintotheholdingmember.9.Conditioning9.1Nailstaplescrewwithdrawaltestsarenmallymadeonseas

36、onedmaterial.Thewoodwoodproductwhetherkilndriedairdriedshallbestedinaroomhavingacontrolledtemperatureof2063C(6866F)acontrolledrelativehuityof6563%faperiodsufficientlylongtobringittoapproximateequilibrium.Thefastenersshal

37、lnotbedrivenuntilequilibriumisattainedinthewoodcomponent.9.2Whererequiredwithdrawaltestsmaybemadeondrierpartiallyseasonedunseasonedmaterial.Itmaysometimesbedesiredtoapplythefastenerstounseasonedmaterialallowthecompleteds

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