Designers' guide to EN 1998-1 and EN 1998-5 Eurocode 8 : design of structures for earthquake resistance : general rules, seismic actions, design rules for buildings, foundations and retaining structures

288 Pages·2005·4.566 MB·English

by  Fardis, Michael N

DESIGNERS’ GUIDES TO THE EUROCODES
DESIGNERS’ GUIDE TO EUROCODE 8:
DESIGN OF STRUCTURES FOR EARTHQUAKE
RESISTANCE
DESIGNERS’ GUIDE TO EN 1998-1 AND EN 1998-5
EUROCODE 8: DESIGN OF STRUCTURES FOR
EARTHQUAKE RESISTANCE GENERAL RULES, SEISMIC
ACTIONS, DESIGN RULES FOR BUILDINGS AND
RETAINING STRUCTURES
Eurocode Designers’ Guide Series
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M.Holicky´.0727730118.Published2002.
Designers’ Guide to EN 1994-1-1. Eurocode 4: Design of Composite Steel and Concrete Structures. Part 1.1:
GeneralRulesandRulesforBuildings.R.P.JohnsonandD.Anderson.0727731513.Published2004.
Designers’ Guide to EN 1997-1. Eurocode 7: Geotechnical Design – General Rules. R. Frank, C. Bauduin,
R.Driscoll,M.Kavvadas,N.KrebsOvesen,T.OrrandB.Schuppener.0727731548.Published2004.
Designers’GuidetoEN1993-1-1.Eurocode3:DesignofSteelStructures.GeneralRulesandRulesforBuildings.
L.GardnerandD.Nethercot.0727731637.Published2004.
Designers’GuidetoEN1992-1-1andEN1992-1-2.Eurocode2:DesignofConcreteStructures.GeneralRules
andRulesforBuildingsandStructuralFireDesign.A.W.BeebyandR.S.Narayanan.072773105X.Published
2005.
Designers’ Guide to EN 1998-1 and EN 1998-5. Eurocode 8: Design of Structures for Earthquake Resistance.
General Rules, Seismic Actions, Design Rules for Buildings, Foundations and Retaining Structures. M. Fardis,
E.Carvalho,A.Elnashai,E.Faccioli,P.PintoandA.Plumier.0727733486.Published2005.
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Buildings.P.Ross.0727731629.Forthcoming:2010(provisional).
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Published2006.
Designers’GuidetoEN1996.Eurocode6:Part1.1:DesignofMasonryStructures.J.Morton.0727731556.
Forthcoming:2010(provisional).
Designers’ Guide to EN 1991-1-2, 1992-1-2, 1993-1-2 and EN 1994-1-2. Eurocode 1: Actions on Structures.
Eurocode 3: Design of Steel Structures. Eurocode 4: Design of Composite Steel and Concrete Structures. Fire
Engineering (Actions on Steel and Composite Structures). Y. Wang, C. Bailey, T. Lennon and D. Moore.
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0727731602.Forthcoming:2010(provisional).
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Traffic Loads and Other Actions on Bridges. J.-A. Calgaro, M. Tschumi, H. Gulvanessian and N. Shetty.
0727731564.Forthcoming:2009(provisional).
Designers’GuidetoEN1991-1-1,EN1991-1-3and1991-1-5to1-7.Eurocode1:ActionsonStructures.General
Rules and Actions on Buildings (not Wind). H. Gulvanessian, J.-A. Calgaro, P. Formichi and G. Harding.
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RulesandRulesforBridges.C.R.HendyandR.P.Johnson.0727731610.Published2006.
www.eurocodes.co.uk
DESIGNERS’ GUIDES TO THE EUROCODES
DESIGNERS’ GUIDE TO EUROCODE 8:
DESIGN OF STRUCTURES FOR EARTHQUAKE
RESISTANCE
DESIGNERS’ GUIDE TO EN 1998-1 AND EN 1998-5
EUROCODE 8: DESIGN OF STRUCTURES FOR
EARTHQUAKE RESISTANCE GENERAL RULES, SEISMIC
ACTIONS, DESIGN RULES FOR BUILDINGS AND
RETAINING STRUCTURES
M. FARDIS, E. CARVALHO, A. ELNASHAI, E. FACCIOLI, P. PINTO
and A. PLUMIER
Series editor
H. Gulvanessian
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Preface
Aim of this guide
ThisDesigners’GuidetoEN1998-1andEN1998-5coverstherulesfortheseismicdesignof
buildingsandfoundations,followingsinaloosewaythecontentsofthesetwoEurocodes.
It summarizes the important points of these two Eurocodes without repeating them,
and provides comments and explanations for their application, as well as background
information.However,itdoesnotelaborateonallclausesofthesetwoEurocodes,neither
doesitfollowstrictlythesequenceofclauses.
Layout of this guide
All cross-references in this guide to sections, clauses, subclauses, paragraphs, annexes,
figures,tablesandexpressionsofEN1998-1andEN1998-5areinitalictype,whichisalso
usedwheretextfromEN1998-1andEN1998-5hasbeendirectlyreproduced(conversely,
quotationsfromothersources,includingotherEurocodes,andcross-referencestosections,
etc.,ofthisguide,areinromantype).ExpressionsrepeatedfromEN1998-1andEN1998-5
retain their numbering; other expressions have numbers prefixed by D (for Designers’
Guide),e.g.equation(D3.1).
Acknowledgements
ThisguidewouldnothavebeenpossiblewithoutthesuccessfulcompletionofEN1998-1and
EN1998-5.Thoseinvolvedintheprocesswere:
(cid:127) NationaldelegatesandnationaltechnicalcontactstoSubcommittee8ofCEN/TC250.
(cid:127) The three project teams of CEN/TC250/SC8 that worked for the conversion from the
ENVstoENs,namelyPT1andPT2forEN1998-1,underthechairmanshipofCarlos
Soussa Oliveira and Jack Bouwkamp, respectively, and PT3 for EN 1998-5, under the
chairmanshipofEzioFaccioli.
The very important technical contributions of Philippe Bisch within the framework of
CEN/TC250/SC8deservesaspecialacknowledgement,andtheauthorswishtoexpresstheir
gratitudeandappreciationforPhilippe’scontribution.
Although not in the list of co-authors, Mauro Dolce of the University of Basilicata and
LuigiDiSarnooftheUniversityofNapoliwhocontributedsignificantlytoChapters9and3,
respectively.Theirhelpisgratefullyacknowledged.
Amongtheco-authors,EzioFaccioliwishestoexpresshisgratitudetoStudioGeotecnico
ItalianoinMilano,foritssupportinthepreparationofChapter10,andinparticulartothe
following individuals who cooperated substantially in the preparation of the examples: A.
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DESIGNERS’GUIDETOEN1998-1ANDEN1998-5
Callerio(whoalsoassistedinthefinalpreparationofthefiguresandthetext),M.Redaelli,
P.Ascari,andR.Andrighetto.HeislikewiseindebtedtoRobertoPaolucci,ofPolitecnicodi
Milano,forprovidingvaluablematerialandfiguresontopographicamplificationandonthe
seismicresponseandstabilityofshallowfoundationsinChapter10.
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Contents
Preface v
Aimofthisguide v
Layoutofthisguide v
Acknowledgements v
Chapter1 Introduction 1
1.1. ScopeofEurocode8 1
1.2. ScopeofEurocode8–Part1 1
1.3. ScopeofEurocode8–Part5 2
1.4. UseofEurocode8–Parts1and5withtheotherEurocodes 2
1.5. Assumptions–distinctionbetweenPrinciplesandApplicationRules 3
1.6. Termsanddefinitions–symbols 3
Chapter2 Performancerequirementsandcompliancecriteria 5
2.1. PerformancerequirementsfornewdesignsinEurocode8and
associatedseismichazardlevels 5
2.2. Compliancecriteriafortheperformancerequirementsandtheir
implementation 7
2.2.1. Compliancecriteriafordamagelimitation 7
2.2.2. Compliancecriteriafortheno-(local-)collapse
requirement 7
2.3. ExemptionfromtheapplicationofEurocode8 10
Chapter3 Seismicactions 13
3.1. Groundconditions 13
3.1.1. Identificationofgroundtypes 14
3.2. Seismicaction 15
3.2.1. Seismiczones 15
3.2.2. Basicrepresentationoftheseismicaction 18
3.2.3. Alternativerepresentationsoftheseismicaction 24
3.3. Displacementresponsespectra 27
Chapter4 Designofbuildings 31
4.1. Scope 31
4.2. Conceptionofstructuresforearthquakeresistantbuildings 31
4.2.1. Structuralsimplicity 31
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4.2.2. Uniformity,symmetryandredundancy 32
4.2.3. Bi-directionalresistanceandstiffness 32
4.2.4. Torsionalresistanceandstiffness 33
4.2.5. Diaphragmaticbehaviouratthestoreylevel 33
4.2.6. Adequatefoundation 34
4.3. Structuralregularityanditsimplicationsfordesign 34
4.3.1. Introduction 34
4.3.2. Regularityinplan 35
4.3.3. Regularityinelevation 41
4.4. Combinationofgravityloadsandotheractionswiththedesign
seismicaction 43
4.4.1. Combinationforlocaleffects 43
4.4.2. Combinationforglobaleffects 43
4.5. Methodsofanalysis 44
4.5.1. Overviewofthemenuofanalysismethods 44
4.5.2. Thelateralforcemethodofanalysis 44
4.5.3. Modalresponsespectrumanalysis 48
4.5.4. Linearanalysisfortheverticalcomponentoftheseismic
action 52
4.5.5. Non-linearmethodsofanalysis 53
4.6. Modellingofbuildingsforlinearanalysis 59
4.6.1. Introduction:thelevelofdiscretization 59
4.6.2. Modellingofbeams,columnsandbracings 60
4.6.3. Specialmodellingconsiderationsforwalls 61
4.6.4. Crackedstiffnessinconcreteandmasonry 62
4.6.5. Accountingforsecond-order(P-∆)effects 63
4.7. Modellingofbuildingsfornon-linearanalysis 64
4.7.1. Generalrequirementsfornon-linearmodelling 64
4.7.2. Specialmodellingrequirementsfornon-lineardynamic
analysis 66
4.7.3. Theinadequacyofmembermodelsin3Dasalimitation
ofnon-linearmodelling 68
4.8. Analysisforaccidentaltorsionaleffects 68
4.8.1. Accidentaleccentricity 68
4.8.2. Estimationoftheeffectsofaccidentaleccentricity
throughstaticanalysis 69
4.8.3. Simplifiedestimationoftheeffectsofaccidental
eccentricity 70
4.9. Combinationoftheeffectsofthecomponentsoftheseismic
action 71
4.10. ‘Primary’versus‘secondary’seismicelements 72
4.10.1. Definitionandroleof‘primary’and‘secondary’seismic
elements 72
4.10.2. Specialrequirementsforthedesignofsecondaryseismic
elements 73
4.11. Verification 74
4.11.1. Verificationfordamagelimitation 74
4.11.2. Verificationfortheno-(local)-collapserequirement 75
4.12. Specialrulesforframesystemswithmasonryinfills 81
4.12.1. Introductionandscope 81
4.12.2. Designagainsttheadverseeffectsofplanwiseirregular
infills 82
4.12.3. Designagainsttheadverseeffectsofheightwiseirregular
infills 83
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CONTENTS
Chapter5 Designanddetailingrulesforconcretebuildings 85
5.1. Scope 85
5.2. Typesofconcreteelements-definitionof‘criticalregions’ 86
5.2.1. Beamsandcolumns 86
5.2.2. Walls 86
5.2.3. Ductilewalls:coupledanduncoupled 87
5.2.4. Largelightlyreinforcedwalls 88
5.2.5. Criticalregionsinductileelements 89
5.3. Typesofstructuralsystemsforearthquakeresistanceof
concretebuildings 89
5.3.1. Inverted-pendulumsystems 90
5.3.2. Torsionallyflexiblesystems 90
5.3.3. Framesystems 90
5.3.4. Wallsystems 91
5.3.5. Dualsystems 91
5.3.6. Systemsoflargelightlyreinforcedwalls 91
5.4. Designconcepts:designforstrengthorforductilityandenergy
dissipation-ductilityclasses 92
5.5. Behaviourfactorqofconcretebuildingsdesignedforenergy
dissipation 93
5.6. Designstrategyforenergydissipation 95
5.6.1. Globalandlocalductilitythroughcapacitydesignand
memberdetailing:overview 95
5.6.2. Implementationofcapacitydesignofconcreteframes
againstplastichingingincolumns 96
5.6.3. Detailingofplastichingeregionsforflexuralductility 101
5.6.4. Capacitydesignofmembersagainstpre-emptiveshear
failure 105
5.7. Detailingrulesforthelocalductilityofconcretemembers 111
5.7.1. Introduction 111
5.7.2. Minimumlongitudinalreinforcementinbeams 111
5.7.3. Maximumlongitudinalreinforcementratiointhecritical
regionsofbeams 112
5.7.4. Maximumdiameteroflongitudinalbeambarscrossing
beam-columnjoints 113
5.7.5. Verificationofbeam-columnjointsinshear 116
5.7.6. Dimensioningofshearreinforcementincriticalregions
ofbeamsandcolumns 120
5.7.7. Confinementreinforcementinthecriticalregionsof
columnsandductilewalls 123
5.7.8. Boundaryelementsatsectionendsinthecriticalregion
ofductilewalls 127
5.7.9. Shearverificationinthecriticalregionofductilewalls 127
5.7.10. Minimumclampingreinforcementacrossconstruction
jointsinwallsofDCH 130
5.8. Specialrulesforlargewallsinstructuralsystemsoflargelightly
reinforcedwalls 131
5.8.1. Introduction 131
5.8.2. DimensioningfortheULSinbendingwithaxialforce 131
5.8.3. DimensioningfortheULSinshear 132
5.8.4. Detailingofthereinforcement 134
5.9. Specialrulesforconcretesystemswithmasonryorconcrete
infills 135
5.10. Designanddetailingoffoundationelements 138
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Chapter6 Designanddetailingrulesforsteelbuildings 141
6.1. Scope 141
6.2. Dissipativeversuslow-dissipativestructures 141
6.3. Capacitydesignprinciple 143
6.4. Designforlocalenergydissipationintheelementsandtheir
connections 144
6.4.1. Favourablefactorsforlocalductility 144
6.4.2. Unfavourablefactorsforlocalductility 145
6.5. Designrulesaimingattherealizationofdissipativezones 146
6.6. Backgroundofthedeformationcapacityrequiredby
Eurocode8 147
6.7. Designagainstlocalizationofstrains 148
6.8. Designforglobaldissipativebehaviourofstructures 150
6.8.1. Structuraltypesandbehaviourfactors 150
6.8.2. Selectionofthebehaviourfactorfordesignpurposes 151
6.9. Moment-resistingframes 152
6.9.1. Designobjective 152
6.9.2. Analysisissuesinmoment-resistingframes 152
6.9.3. Designofbeamsandcolumns 153
6.9.4. Designofdissipativezones 156
6.9.5. Limitationofoverstrength 157
6.10. Frameswithconcentricbracings 158
6.10.1. Analysisofframeswithconcentricbracingsconsidering
theirevolutivebehaviour 158
6.10.2. SimplifieddesignofframeswithXbracings 159
6.10.3. Simplifieddesignofframeswithdecoupleddiagonal
bracings 159
6.10.4. SimplifieddesignofframeswithVbracings 160
6.10.5. Criterionfortheformationofaglobalplasticmechanism 160
6.10.6. Partialstrengthconnections 160
6.11. Frameswitheccentricbracings 161
6.11.1. Generalfeaturesofthedesignofframeswitheccentric
bracings 161
6.11.2. Shortlinksversuslonglinks 162
6.11.3. Criteriatoformaglobalplasticmechanism 163
6.11.4. Selectionofthetypologyofeccentricbracings 164
6.11.5. Partialstrengthconnections 164
6.12. Moment-resistingframeswithinfills 165
6.13. Controlofdesignandconstruction 165
Chapter7 Designanddetailingofcompositesteel-concretebuildings 167
7.1. Introductoryremark 167
7.2. Degreeofcompositecharacter 167
7.3. Materials 168
7.4. Designforlocalenergydissipationinelementsandtheir
connections 168
7.4.1. Favourablefactorsforlocalductilityduetothe
compositecharacterofstructures 168
7.4.2. Unfavourablefactorsforlocalductilityduetothe
compositecharacterofstructures 169
7.5. Designfortheglobaldissipativebehaviourofstructures 170
7.5.1. Behaviourfactorsofstructuraltypessimilartosteel 170
7.5.2. Behaviourfactorsofcompositestructuralsystems 171
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