Handbook of Structural Steel Connection Design and Details

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CONTENTS

Contributors
PrefacetotheThirdEdition

PrefacetotheFirstEdition
Acknowledgments
Chapter1.FastenersandWeldsforStructuralConnectionsLarryS.Muir,P.E.,William
A.Thornton,Ph.D.,P.E.,andThomasKane,C.Eng.,M.I.Struct.E.
1.1Introduction
1.2BoltedConnections
1.2.1TypesofBolts
1.2.2WasherRequirements
1.2.3PretensionedandSnug-TightBolts
1.2.4Bearing-TypeversusSlip-CriticalJoints
1.2.5BoltsinCombinationwithWelds
1.2.6Standard,Oversized,Short-Slotted,andLong-SlottedHoles
1.2.7EdgeDistancesandSpacingofBolts
1.2.8Installation
1.3WeldedConnections
1.3.1TypesofWelds
1.3.2WeldingSymbols
1.3.3WeldingMaterial
1.3.4WeldingPositions
1.3.5WeldProcedures
1.3.6WeldQuality
1.3.7MethodsforDeterminingStrengthofSkewedFilletWelds
1.3.8ObliquelyLoadedConcentricFilletWeldGroups
References
Chapter2.DesignofConnectionsforAxial,Moment,andShearForcesLarryS.Muir,
P.E.,WilliamA.Thornton,Ph.D.,P.E.,andThomasKane,C.Eng.,M.I.Struct.E.
2.1Introduction


2.1.1Philosophy

2.1.2GeneralProcedure
2.1.3EconomicConsiderations
2.1.4TypesofConnections
2.1.5Organization
2.2AxialForceConnections
2.2.1BracingConnections
2.2.2TrussConnections
2.2.3HangerConnections
2.2.4ColumnBasePlates
2.2.5Splices—ColumnsandTrussChords
2.3MomentConnections
2.3.1Introduction
2.3.2Example:Three-WayMomentConnection
2.4ShearConnections
2.4.1Introduction
2.4.2FramedConnections
2.4.3SkewedConnections
2.4.4SeatedConnections
2.4.5BeamShearSplices
2.4.6ExtendedSingle-PlateShearConnections(ShearTabs)
2.5MiscellaneousConnections
2.5.1SimpleBeamConnectionsunderShearandAxialLoad
2.5.2ReinforcementofAxialForceConnections
2.5.3ExtendedTabwithAxial
References
Chapter3.WeldedJointDesignandProductionDuaneK.Miller,Sc.D.,P.E.,and
MichaelD.Florczykowski
3.1Introduction
3.2WeldingCodesandStandards
3.2.1AISCSpecifications

3.2.2AWSSpecifications
3.3StructuralSteelsforWeldedConstruction
3.3.1AWSD1.1SteelListings
3.3.2AISCSpecificationTreatmentofUnidentifiedSteels
3.3.3WeldingRequirementsforSpecificSteels


3.4WeldingandThermalCuttingProcesses
3.4.1ShieldedMetalArcWelding
3.4.2FluxCoredArcWelding
3.4.3GasMetalArcWelding
3.4.4SubmergedArcWelding
3.4.5GasTungstenArcWelding
3.4.6ArcStudWelding
3.4.7ElectroslagWelding
3.4.8OxyfuelCutting
3.4.9PlasmaArcCutting
3.4.10AirCarbonArcCuttingandGouging
3.5WeldedJointDesign
3.5.1CJPGrooveWelds
3.5.2PJPGrooveWelds
3.5.3FilletWelds
3.6WeldingProcedures
3.6.1EffectsofWeldingVariables
3.6.2PurposeofWeldingProcedureSpecifications
3.6.3PrequalifiedWeldingProcedureSpecifications
3.6.4GuidelinesforPreparingPrequalifiedWPSs
3.6.5QualifyingWeldingProceduresbyTest
3.6.6ApprovalofWPSs
3.7WeldingCostAnalysis

3.8WeldingProblems:CrackingandTearingduringFabrication
3.8.1CenterlineCracking
3.8.2UnderbeadCracks
3.8.3TransverseCracks
3.8.4LamellarTearing
3.9WeldingProblems:Distortion
3.10WeldingonExistingStructures
3.10.1SafetyPrecautions
3.10.2ExistingSteelCompositionandCondition
3.10.3WeldingandCuttingonMembersunderLoad
3.10.4ModificationsandAdditionstoUndamagedSteel
3.10.5RepairofPlasticallyDeformedSteel
3.11WeldingonSeismicallyResistantStructures
3.11.1HighConnectionDemands
3.11.2StressConcentrations


3.11.3FractureResistance
3.11.4DemandCriticalConnectionsandProtectedZones
3.11.5SeismicWeldedConnectionDetails
3.11.6FillerMetalRequirements
3.11.7WelderQualificationTests
3.11.8NondestructiveTesting
3.12Acknowledgments
References
Chapter4.PartiallyRestrainedConnectionsRobertoT.Leon
4.1Introduction
4.2ConnectionClassification
4.2.1ConnectionStiffness
4.2.2ConnectionStrength

4.2.3ConnectionDuctility
4.2.4DerivationofM-θCurves
4.2.5Analysis
4.3DesignofBoltedPRConnections
4.3.1ColumnWelded-BeamBoltedConnections
4.3.2ColumnBolted-BeamBolted(TStubs)
4.3.3End-PlateConnections
4.4FlexiblePRConnections
4.5ConsiderationsforAnalysisofPRFrames
References
Chapter5.SeismicDesignofConnectionsJamesO.MalleyandRaymondS.Pugliesi
5.1SpecialDesignIssuesforSeismicDesign
5.2ConnectionDesignRequirementsforVariousStructuralSystems
5.3DesignofSpecialMoment-FrameConnections
5.3.1Introduction
5.3.2Post-NorthridgeDevelopmentsinConnectionDesign
5.3.3ToughenedConnections
5.3.4StrengthenedConnections
5.3.5WeakenedConnections
5.4ConcentricallyBracedFrames
5.4.1Introduction


5.4.2ConnectionDesignandExample
5.5EccentricallyBracedFrames
5.6BucklingRestrainedBracedFrames
5.7SpecialPlateShearWalls
5.8OtherConnectionsinSeismicFrames
References
Chapter6.StructuralSteelDetailsDavidR.Williams,P.E.

Reference
Chapter7.ConnectionDesignforSpecialStructuresLawrenceA.Kloiber
7.1Introduction
7.2LateralLoadSystems
7.3Long-SpanTrusses
7.4Space-FrameStructures
7.5ExamplesofConnectionsforSpecialStructures
7.6BuildingInformationModel
7.7Conclusion
References
Chapter8.QualityControlandQualityAssuranceRobertE.Shaw,Jr.,P.E.
8.1PrinciplesofQualityControlandQualityAssurance
8.2StandardsforQCandQA
8.3Fabricator ’sandErector ’sQCPrograms
8.3.1FabricatorandErectorQCActivities
8.3.2QCInspectionPersonnel
8.3.3FabricatorandErectorApprovals
8.4QualityAssurancePrograms
8.4.1QAInspectionActivities
8.4.2QAInspectionPersonnel
8.4.3NondestructiveTestingPersonnel
8.5InspectionofBoltedConnections
8.5.1ScopeofInspections
8.5.2InspectionpriortoBolting
8.5.3InspectionduringBolting
8.5.4InspectionafterBolting


8.6InspectionofWeldedConnections
8.6.1AdvanceInspection

8.6.2InspectionpriortoWelding
8.6.3InspectionduringWelding
8.6.4InspectionafterWelding
8.6.5NondestructiveTesting
8.6.6WeldAcceptanceCriteria
Chapter9.SteelDeckConnectionsThomasSputo,Ph.D.,P.E.,S.E.,RichardB.Heagler,
P.E.,andJohnMattingly
Chapter10.ConnectionstoCompositeMembersAtorodAzizinamini,Ph.D.,P.E.,
BahramShahrooz,Ph.D.,AhmedEl-Remaily,Ph.D.,P.E.,andHassanAstaneh,Ph.D.,P.E.
10.1Introduction
10.2GeneralDesignConsiderations
10.2.1StrengthandStiffness
10.2.2Stability
10.2.3Serviceability
10.2.4CyclicBehavior
10.3Beam-to-WallConnections
10.3.1IntroductoryRemarks
10.3.2QualitativeDiscussionAboutOutriggerBeam-WallConnectionandCoupling
Beam-WallConnection
10.3.3DesignofSteelorSteel-ConcreteCompositeCouplingBeam-WallConnections
10.3.4DesignofOutriggerBeam-WallConnections
10.4JointsBetweenSteelBeamsandReinforcedConcreteColumns
10.4.1Introduction
10.4.2JointBehavior
10.4.3JointDetailing
10.4.4JointForces
10.4.5EffectiveJointWidth
10.4.6StrengthRequirements
10.4.7Limitations
10.5ConnectionstoConcrete-FilledTube(CFT)Columns

10.5.1Introduction
10.5.2CurrentPractice
10.5.3ProblemsAssociatedwithWeldingBeamstoCFTColumns


10.5.4PossibleConnectionDetail
10.5.5ForceTransferMechanismforThrough-BeamConnectionDetail
10.5.6TentativeDesignProvisionsforThrough-BeamConnectionDetail
10.6Notations(ForSec.10.3)
References
AppendixA.StructuralShapes—DimensionsandGeneralInformation
AppendixB.WeldingSymbols
AppendixC.SIMetricConversionTable
AppendixD.Nomenclature
Index



CONTRIBUTORS

HassanAstaneh,Ph.D.,P.E.Professor,DepartmentofCivilEngineering,Universityof
California,Berkeley,California(Chap.10)
AtorodAzizinamini,Ph.D.,P.E.Professor,CivilEngineeringDepartment,Universityof
Nebraska,Lincoln,Nebraska,andNationalBridgeResearchOrganization(NaBRO),
UniversityofNebraska,Lincoln,Nebraska(Chap.10)
AhmedEl-Remaily,Ph.D.,P.E.UniversityofNebraska,Lincoln,Nebraska(Chap.10)
MichaelD.Florczykowski,TheLincolnElectricCompany,Cleveland,Ohio(Chap.3)
RichardB.Heagler,P.E.Retired;formerly,NicholasJ.Bouras,Inc.,MurrayHill,New
Jersey(Chap.9)
ThomasKane,C.Eng.,M.I.Struct.E.Retired;formerly,TechnicalManager,CivesSteel

Company,Roswell,Georgia(Chaps.1,2)
LawrenceA.KloiberLeJeuneSteel,Minneapolis,Minnesota(Chap.7)
RobertoT.LeonD.H.BurrowsProfessorofConstructionEngineering,ViaDepartmentof
CivilandEnvironmentalEngineering,VirginiaTech,Blacksburg,Virginia(Chap.4)
JamesO.MalleySeniorPrincipal,DegenkolbEngineers,SanFrancisco,California(Chap.
5)
JohnMattinglyRetired;formerly,CMCJoist&Deck,MurrayHill,NewJersey(Chap.9)
DuaneK.Miller,Sc.D.,P.E.TheLincolnElectricCompany,Cleveland,Ohio(Chap.3)
LarryS.Muir,P.E.DirectorofTechnicalAssistance,AmericanInstituteofSteel
Construction,Atlanta,Georgia(Chaps.1,2)
RaymondS.PugliesiPrincipal,DegenkolbEngineers,SanFrancisco,California(Chap.5)
BahramShahrooz,Ph.D.Professor,CivilEngineeringDepartment,Universityof
Cincinnati,Cincinnati,Ohio(Chap.10)
RobertE.Shaw,Jr.,P.E.President,SteelStructuresTechnologyCenter,Inc.,Howell,
Michigan(Chap.8)
ThomasSputo,Ph.D.,P.E.,S.E.TechnicalDirector,SteelDeckInstitute,Gainesville,
Florida(Chap.9)
AkbarR.Tamboli,P.E.F.ASCEConsultant,ThorntonTomasetti,Newark,NewJersey
(Apps.A,B,C,D)
WilliamA.Thornton,Ph.D.,P.E.CorporateConsultant,CivesSteelCompany,Roswell,


Georgia(Chaps.1,2)
DavidR.Williams,P.E.Principal,WilliamsEngineeringAssociates,VirginiaBeach,
Virginia(Chap.6)


ABOUTTHEEDITOR
AkbarR.Tamboli,P.E.,F.ASCE,isaconsultantatThorntonTomasettiinNewYork.Hehas
beenaseniorprojectengineerwithCUH2AinPrinceton,NewJersey,acompanythat

specializedinarchitecture,engineering,andplanning.Hehasalsobeenavicepresidentand
projectmanageratCantor-SeinukGroupPC,ConsultingEngineers,inNewYork,wherehe
wastheprincipalconsultingengineeronanumberofnoteworthyprojects,includingMorgan
GuarantyBankHeadquartersat60WallStreetandSalomonBrothersWorldHeadquarters,
SevenWorldTradeCenter.
Mr.TamboliwasseniorvicepresidentandprincipalatThorntonTomasetti,wherehe
designedandmanagedseveralaward-winningprojects,includingRandomHouseWorld
HeadquartersinNewYork;theUniversityofPennsylvania’sPerelmanCenterforAdvanced
MedicineandRobertsProtonTherapyCenter;JaneliaResearchCampusoftheHoward
HughesMedicalInstituteinLeesburg,Virginia;theNeuroscienceResearchCenteratthe
NationalInstitutesofHealthinBethesda,Maryland;andCarrascoInternationalAirportin
Montevideo,Uruguay.
HedesignedandmanagedseveralconcreteandsteelprojectsinEurope,Asia,andthe
MiddleEast.Mr.TambolihasalsopublishedthreeengineeringhandbookswithMcGraw-Hill,
includingTallandSupertallBuildings:PlanningandDesignandSteelDesignHandbook:
LRFDMethod,andcontributedchapterstoMcGraw-Hill’sStandardHandbookforCivil
EngineersandBuildingDesignandConstructionHandbook.



PREFACETOTHETHIRDEDITION

SincethepreviouseditionofthisbookwaspublishedinOctober2009,therehavebeenmany
developmentsinthevariousaspectsofsteelconnectiondesign.Improvedfabricationand
constructiontechniqueshaveledtoefficientstructuralconnections.
ThenewAISCcodeprovisionsfor2016havebeenincorporatedinthisnewedition.AISC
provisionshavebeenreferencedinandmadepartoftheInternationalBuildingCode.
Chapters1and2havebeenreworkedtoreflectthe2016AISCcodeprovisions.Chapter3
onweldinghasbeencompletelyrewrittentoincorporatenewweldingcodesandthe2016
AISCcodeprovisions.Newinformationhasbeenaddedonstate-of-the-artwelding

proceduresandspecialprecautionsneededforweldedjointsinseismicallyactiveregions.
Partiallyrestrainedconnections,coveredinChap.4,havebeenevolvingandhavebeen
madepartoftheAISCcode.Thischapterhasbeenrewrittenwithseveralexamples.
Seismicconnectionandstructuraldesign,addressedinChap.5,havebeenimproving.This
chapterhasbeenrevisedtoreflecttheimprovementswithactualexamples.
Chapter6,onstructuraldetails,canbefoundatwww.mhprofessional.com/tamboli.
Newconstructionandfabricationmethodsusedforrecentspecialstructuresaredescribed
inChap.7.Chapter8,onqualitycontrolandinspection,hasbeencompletelyrewritten.In
manycases,theprojectsfeaturedinthischapterareinternational;therefore,bothmetricand
Englishunittolerancesaregiven.
Chapter9onsteeldeckshasbeencompletelyupdatedtomeetSteelDeckInstitute(SDI)
requirements.
Chapter10oncompositeconstructionconnectionscanbefoundat
www.mhprofessional.com/tamboli.
Theeditorwishestothankthecontributorsfortheireffortsinpreparingexcellent
manuscripts.
Theeditorandthecontributorsaregratefultoseveralsourcesforprovidingthe
informationpresented.Spaceconsiderationsprecludelistingallofthem,butcreditisgiven
whereverfeasible,especiallyinreferencesthroughoutthebook.
Usersofthishandbookarewelcometocommunicatewiththeeditorregardinganyaspect
ofthebook,particularlysuggestionsforimprovement.
AkbarR.Tamboli



PREFACETOTHEFIRSTEDITION

TheneedfortheHandbookofStructuralSteelConnectionDesignandDetailswithanLRFD
approachwasrecognizedatthetimetheSteelDesignHandbook:LRFDMethodwas
published.

Thishandbookwasdevelopedtoserveasacomprehensivereferencesourceforthedesign
ofsteelconnectionsusingtheLRFDmethod.Eachtopiciswrittenbyleadingexpertsinthe
field.Emphasisisgiventoprovideexamplesfromactualpractice.Examplesarefocusedto
giveacost-effectiveapproach.Thetheoryandcriteriaareexplainedandcross-referencesto
equationstoAISCaregivenwhereapplicable.
Thebookstartswithadiscussionoffastenersforstructuralconnections.Itthengoesinto
thedesignofconnectionsforaxial,moment,andshearforces.Detailedconnectiondesign
aspectsarecoveredinthischapter.
Weldedjointdesignandproductionaretreatedasaseparatetopic,andstate-of-the-art
informationonweldingisgivenforuseindailypractice.Howtocontrolweldcrackingand
jointdistortionisexplainedforuseingeneralconsultingpractice.Partiallyrestrained
connectiondesignisexplainedwithpracticalexamples.
Recentseismicactivityhascreatedtheneedforthedesignofconnectionsforseismically
resistantstructures.Thesetypesofconnectionsarecoveredwithdetailedexamples.
Commonlyusedconnectiondetailsareshownforuseindailypracticebyfabricator,detailer,
andconsultingengineer.
Sometimesfabricatorsandengineersneedtodesignconnectionsforspecialstructures.
Actualexamplesofhowtoapproachtheseneedsaregivenfromrealprojectswhicharebuilt.
Toensurequalityofconnection,constructioninspectionandqualitycontrolarevital.
Therefore,detailedinformationontheseaspectsisgiventoachievedesiredgoals.
Moststeelstructureshavesteeldecking.Toensuregoodqualityandinteraction,steeldeck
detailsareexplainedthoroughly.
Thelatesttrendincompositeconstructionhascreatedtheneedforthedesignofcomposite
constructionconnections.Steel-to-concreteshearwallandcompositecolumnconnectionsare
explainedindetailtoachieveproperinteractionandstrength.
Theeditorgratefullyacknowledgestheeffortsofcontributorsinpreparingexcellent
manuscripts.ThanksareduetothemanagementandstaffatCUH2A,Inc.
Theeditorandauthorsareindebtedtoseveralsourcesfortheinformationpresented.
Spaceconsiderationsprecludelistingall,butcreditisgivenwhereverfeasible,especiallyin
referencesthroughoutthebook.

Usersofthishandbookareurgedtocommunicatewiththeeditorregardingallaspectsof
thisbook,particularlyanyerrororsuggestionforimprovement.
AkbarR.Tamboli



ACKNOWLEDGMENTS

Theeditorwouldliketoacknowledgetheinputandhelpreceivedfrommanypeople,
especiallythoselistedbelowforthetimeandencouragementtheyprovided:
•OmerBlodgett,TheLincolnElectricCompany
•TheodoreGalmbos,UniversityofMinnesota
•LynnBeedle,LehighUniversity
AppreciationisexpressedtoAlPerryofCUH2A,Inc.,Princeton,NewJersey,forhis
encouragementduringthepreparationofthishandbook,andIrwinCantorandYsraelSeinuk
ofCantor-SeinukGroupofNewYork,forencouragingtheuseoftheLRFDapproachin
majorprojectslikeSevenWorldTradeCenter,NewYork;NewportOfficeTower,Jersey
City,NewJersey;andChaseMetrotechComplex,Brooklyn,NewYork.
TheeditorwouldalsoliketoacknowledgethehelpandassistanceprovidedbyLauren
Poplawski,sponsoringeditorofthishandbook,whoputforthinvaluablesupportduringthe
processofpreparingthemanuscript.Also,thanksgotothemanyotherindividualsat
McGraw-HillandatCenveowhowereresponsibleforbringingthebooktopress,including
LynnMessinaandStephenSmith,andSrishtiMalasi,projectmanager.
Theeditorwishestoextendhisthanksandappreciationtohiswife,Rounkbi,andhis
children,Tahira,Ajim,andAlamgir,fortheirpatienceandunderstandingduringthe
preparationofthishandbook.


CHAPTER1
FASTENERSANDWELDSFORSTRUCTURAL

CONNECTIONS
LarryS.Muir,P.E.DirectorofTechnicalAssistance,AmericanInstituteofSteel
Construction,Atlanta,Georgia

WilliamA.Thornton,Ph.D.,P.E.CorporateConsultant,CivesSteelCompany,
Roswell,Georgia

ThomasKane,C.Eng.,M.I.Struct.E.Retired;formerly,TechnicalManager,Cives
SteelCompany,Roswell,Georgia

(CourtesyofTheSteelInstituteofNewYork.)

1.1INTRODUCTION
Therearetwocommonwaystoconnectstructuralsteelmembers—usingboltsorwelds.
Rivets,whilestillavailable,arenotcurrentlyusedfornewstructuresandwillnotbe


consideredhere.Thischapterwillpresentthebasicpropertiesandrequirementsforboltsand
welds.
Connectionsareanintimatepartofasteelstructureandtheirpropertreatmentisessential
forasafeandeconomicstructure.Anintuitiveknowledgeofhowasystemwilltransmitloads
(theartofloadpaths),andanunderstandingofstructuralmechanics(thescienceof
equilibriumandlimitstates),arenecessarytoachieveconnectionswhicharebothsafeand
economic.Chapter2willdevelopthismaterial.Thischapterisbasedontheboltingand
weldingrequirementspecificationsoftheAmericanInstituteofSteelConstruction(AISC),
“SpecificationforStructuralSteelBuildings,”2016,andtheAmericanWeldingSociety
StructuralWeldingCode,D1.1(2010).

1.2BOLTEDCONNECTIONS
1.2.1TypesofBolts

Therearetwokindsofboltsusedinsteelconstruction.Thesearehigh-strengthstructural
bolts(Fig.1.1)andcommonboltsmanufacturedunderASTMA307(Fig.1.2).High-strength
boltsareincludedinthreeseparateAmericanSocietyforTestingandMaterials(ASTM)
Specifications:F3125,F3043,andF3111.F3125isanumbrellaspecificationthatincludesfour
grades:A325,A490,F1852,andF2280.TheAISCSpecificationdivideshigh-strengthbolts
intothreegroupsbasedonminimumtensilestrength.GroupAboltshaveaminimumtensile
strengthof120ksiandincludeASTMF3125GradesA325,A325M,andF1852,aswellas
ASTMA354GradeBC.GroupBboltshaveaminimumtensilestrengthof150ksiand
includeASTMF3125GradesA490,A490M,andF2280,aswellasA354GradeBD.GroupC
boltshaveaminimumtensilestrengthof200ksiandincludeASTMF3043andASTMA3111.
ThevariousgradesofF3125areintendedforgeneralstructuraluse,withtheuseofA354and
A449fastenersintendedonlyforconditionswherethelengthordiameterlimitsofF3125
mustbeexceeded.F3034andF3111areprobablybestsuitedtoheavilyloadedconnections.
A449boltsarealsopermittedtobeusedwherethelengthanddiameterlimitationsforA325
areexceeded.TheyarenotincludedinGroupAduetothemultipledecreasesintensile
strengthbasedondiameter.A307bolts,whichwerereferredtopreviouslyascommonbolts,
arealsovariouslycalledmachinebolts,ordinarybolts,andunfinishedbolts.Theuseofthese
boltsislimitedprimarilytoshearconnectionsinnonfatigueapplications.

FIGURE1.1High-strengthstructural-steelboltandnut.


FIGURE1.2Unfinished(machine)orcommonbolts.

Structuralboltscanbeinstalledpretensionedorsnugtight.Pretensionedmeansthatthe
boltistighteneduntilatensionforceapproximatelyequalto70percentofitsminimum
tensilestrengthisproducedinthebolt.Snugtightistheconditionthatexistswhenallpliesare
incontact.Itcanbeattainedbyafewimpactsofanimpactwrenchorthefulleffortofaman
usinganordinaryspudwrench.Commonbolts(A307)canbeinstalledonlytothesnug-tight
condition.Thereisnorecognizedprocedurefortighteningtheseboltsbeyondthispoint.

Pretensionedstructuralboltsmustbeusedincertainlocations.SectionJ3.1oftheAISC
specificationrequiresthattheybeusedforthefollowingjoints:
1.Jointsthataresubjecttosignificantloadreversal
2.Jointsthataresubjecttofatigueloadwithnoreversaloftheloadingdirection
3.JointswithASTMA325orF1852boltsthataresubjecttotensilefatigue
4.JointswithASTMA490orF2280boltsthataresubjecttotensionorcombinedshearand
tension,withorwithoutfatigue
5.Connectionssubjectedtovibratoryloadswhereboltlooseningisaconsideration
6.Endconnectionsofbuilt-upmemberscomposedoftwoshapeseitherinterconnectedby
boltsorwithatleastoneopensideinterconnectedbyperforatedcoverplatesorlacing
withtieplates,asrequiredinSectionE6.1oftheAISCSpecification
Inallothercases,A307boltsandsnug-tightA325andA490boltscanbeused.
TheuseofASTMF3125structuralboltsshallconformtotherequirementsofthe
ResearchCouncilonStructuralConnections(RCSC)“SpecificationforStructuralJoints
UsingBolts,”2004.Thisdocumentcontainsalloftheinformationondesign,installation,
inspection,washeruse,compatiblenuts,etc.forthesebolts.Informationontheinstallation,
inspection,washeruse,compatiblenuts,etc.forF3043andF3111boltsiscontainedinthe
ASTMSpecifications.ThereisnocomparabledocumentforA307bolts.TheRCSC“bolt
spec.”wasdevelopedinthe1950stoallowthereplacementofrivetswithbolts.
Manysizesofhigh-strengthboltsareavailable,asshowninTable1.1.Ingeneral,a
connectionwithafewlarge-diameterfastenerscostslessthanoneofthesamecapacitywith
manysmall-diameterfasteners.Thefewerthefasteners,thefewerthenumberofholestobe
formedandthelessinstallationwork.Larger-diameterfastenersaregenerallyfavorablein
connections,becausetheloadcapacityofafastenervarieswiththesquareofthefastener