probabilistic structural seismic performance assessment methodology and application to an actual ...

360 Pages·2006·12.73 MB·English

UC San Diego
UC San Diego Electronic Theses and Dissertations
Title
Probabilistic structural seismic performance assessment methodology and application to an
actual bridge-foundation -ground system
Permalink
https://escholarship.org/uc/item/9jh5t476
Author
Zhang, Yuyi
Publication Date
2006

Peer reviewed|Thesis/dissertation
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University of California
UNIVERSITYOFCALIFORNIA,SANDIEGO
PROBABILISTIC STRUCTURAL SEISMIC PERFORMANCE
ASSESSMENT METHODOLOGY AND APPLICATION TO AN ACTUAL
BRIDGE-FOUNDATION-GROUND SYSTEM
Adissertationsubmitted inpartial satisfactionofthe
requirement forthedegreeofDoctorofPhilosophy
in
Structural Engineering
by
Yuyi Zhang
Committeeincharge:
ProfessorJoel P.Conte,Chair
ProfessorDavidJ.Benson
ProfessorAhmedW.Elgamal
ProfessorJ.Enrique Luco
ProfessorHidenori Murakami
2006
©Copyright
Yuyi Zhang,2006
All rights reserved
The dissertation of Yuyi Zhang is approved, and it
is acceptable in quality and form for publication on
microfilm:
__________________________________________
__________________________________________
__________________________________________
__________________________________________
__________________________________________
Chair
UniversityofCalifornia, SanDiego
2006
iii
Table of Contents
SignaturePage ..............................................................................................................iii
TableofContents..........................................................................................................iv
List of Figures..............................................................................................................viii
List ofTables...............................................................................................................xix
Acknowledgements...................................................................................................xxiii
Vita ...........................................................................................................................xxiii
Abstract......................................................................................................................xxvi
1 Introduction..............................................................................................................1
1.1 Background....................................................................................................1
1.2 Project Objectives andScope.........................................................................8
1.3 OrganizationofText....................................................................................11
2 PEER Performance-BasedEarthquakeEngineeringMethodology.......................14
2.1 PEER ProbabilisticFrameworkEquation....................................................14
2.2 ProbabilisticSeismicHazardAnalysis........................................................17
2.3 ProbabilisticSeismicDemandAnalysis......................................................22
2.4 ProbabilisticSeismicDamageAnalysis......................................................23
2.5 ProbabilisticSeismicLoss Analysis............................................................24
3 Humboldt BayMiddleChannel Bridge..................................................................26
3.1 DescriptionofStructure...............................................................................26
3.2 DescriptionofSiteConditions.....................................................................29
3.3 FaultingandSeismicity................................................................................32
3.4 SeismicRetrofits..........................................................................................33
4 ProbabilisticSeismicHazardAnalysis of Humboldt BayBridgeSite...................35
4.1 Introduction..................................................................................................35
iv
4.2 SeismicSources...........................................................................................36
4.3 Uniform HazardSpectra..............................................................................37
4.4 DeaggregationofSeismicHazard................................................................41
4.5 Process ofSelectingGroundMotionRecordings........................................46
4.5.1 TimeHistories for50%in50Years................................................46
4.5.2 TimeHistories for10%in50Years................................................48
4.5.3 TimeHistories for2%in 50Years..................................................49
4.6 RepresentationofNear Fault RuptureDirectivityEffects intheGround
MotionRecordings.......................................................................................51
4.7 RepresentationofStatic GroundDisplacements intheGroundMotion
Recordings...................................................................................................52
4.8 Scalingofthe GroundMotionRecordings..................................................53
5 ProbabilisticSeismicDemandAnalysis -Part I: Computational Model ofthe
Humboldt BayMiddleChannel Bridgeand PreliminaryAnalyses.......................55
5.1 Introduction..................................................................................................55
5.2 Computational Model..................................................................................60
5.2.1 FoundationSoil................................................................................62
5.2.2 Structure...........................................................................................66
5.2.2.1 Abutments.........................................................................66
5.2.2.2 Girders...............................................................................67
5.2.2.3 LapSplicedPiers..............................................................67
5.2.2.4 PileGroupFoundations andPileCaps.............................73
5.2.2.5 ShearKeys at ExpansionandContinuous Joints..............75
5.2.3 BoundaryConditions of Computational Soil Domainand
DefinitionofSeismic Input..............................................................78
5.2.3.1 Lysmer-TypeTransmitting/AbsorbingBoundaryand
DefinitionofSeismic Input...............................................78
5.2.3.2 Numerical Verification.....................................................82
5.2.4 Inertiaand DampingProperties.......................................................85
5.3 DeconvolutionAnalysis ofSurfaceFree FieldGroundMotions................86
5.4 StagedAnalysis Procedure..........................................................................89
5.5 StaticPushoverAnalysis..............................................................................91
5.6 Small AmplitudeVibrationAnalysis...........................................................98
5.7 EarthquakeResponseAnalysis..................................................................104
5.8 Effects ofSoil BoundaryConditions.........................................................124
5.9 Conclusions................................................................................................131
6 ProbabilisticSeismicDemandAnalysis -Part II: SeismicDemandHazard.......133
6.1 DerivationofSeismicDemandHazardCurve...........................................133
6.2 Potential FailureMechanism and AssociatedEDPs..................................138
6.2.1 FailureofShear Keys.....................................................................139
6.2.2 FailureofBridgePiers...................................................................142
6.2.2.1 Flexural Failure...............................................................142
v
6.2.2.2 ShearFailure...................................................................146
6.2.3 Unseating.......................................................................................149
6.3 CorrelationAnalysis of EDPs....................................................................151
6.4 Conditional ResponseAnalysis Given IM.................................................162
6.5 SeismicDemandHazard Curves................................................................172
6.6 Efficiencyof IMs.......................................................................................178
7 ProbabilisticSeismicDamageAnalysis -Part I: DeterministicSystem
Properties..............................................................................................................188
7.1 Introduction................................................................................................188
7.2 ReliabilityFormulationandComputation.................................................193
7.3 Performance-BasedDamageStates for Various FailureMechanisms......197
7.3.1 DefinitionofDamageStates..........................................................197
7.3.2 DamageStates forPierFlexural FailureMechanism....................201
7.3.3 DamageStates forShear KeyFailureMechanism........................204
7.3.4 DamageStates forUnseatingFailureMechanism.........................206
7.4 DeterministicCapacityModels..................................................................206
7.4.1 PredictiveModel ofPier Flexural Capacity...................................206
7.4.2 PredictiveModel ofShearKeyCapacity.......................................213
7.4.3 PredictiveModel ofUnseatingCapacity.......................................218
7.5 FragilityAnalysis.......................................................................................218
7.6 SeismicReliabilityAnalysis......................................................................223
8 ProbabilisticSeismicDamageAnalysis -Part II: Random System Properties....231
8.1 Introduction................................................................................................231
8.2 Uncertainties ExplicitlyConsideredinPEER FrameworkEquations.......237
8.3 SeismicReliabilityAnalysis MethodologyincludingRandomness in
System Properties.......................................................................................239
8.4 Inherent Randomness in Structural andGeotechnical Properties..............245
8.4.1 UncertaintyinStructural Mass andGravityLoads........................245
8.4.2 UncertaintyintheStructural Material Properties..........................245
8.4.3 UncertaintyintheSoil Material Properties....................................247
8.5 NonlinearTimeHistoryAnalysis with LatinHypercubeSampling..........250
8.6 SensitivityofStructural SeismicDemandtoRandomness inSystem
Properties...................................................................................................252
8.7 ProbabilisticSeismicDemandAnalysis....................................................273
8.8 FragilityCurves IncorporatingRandomness inStructural Properties.......279
8.9 SeismicReliabilityAnalysis......................................................................284
8.10 Conclusions................................................................................................288
9 ProbabilisticSeismicLoss Analysis.....................................................................291
9.1 Introduction................................................................................................291
9.2 Building-Specific Loss Estimation............................................................293
9.3 Loss Analysis throughMultilayerMonteCarloSimulation......................298
vi
9.3.1 Random GenerationofIM.............................................................298
9.3.2 Random GenerationofEDPs.........................................................298
9.3.3 Random GenerationofDMs..........................................................300
9.3.4 Random GenerationofComponent Repair/Replacement Cost.....301
10 ConcludingRemarks............................................................................................307
10.1 Summaryofwork......................................................................................307
10.2 Summaryof Findings.................................................................................311
10.3 Recommendations for FutureResearch:....................................................316
References..................................................................................................................319
vii
List of Figures
Fig.2.1: PEER PBEEmethodology(Porter2003).................................................15
Fig.2.2: ProcedureofPSHA...................................................................................19
Fig.3.1: Humboldt BayBridges .............................................................................27
Fig.3.2: Aerial view of Humboldt Bay Middle Channel Bridge (courtesy of
Caltrans)....................................................................................................28
Fig.3.3: Superstructure andsubstructureofHBMC Bridge...................................28
Fig.3.4: Abutment joint ofHBMC Bridge.............................................................28
Fig.3.5: Interiorexpansionjoint ofHBMC Bridge................................................29
Fig.3.6: Continuous joint ofHBMC Bridge...........................................................29
Fig.3.7: Two-dimensional soil profile of HBMC Bridge site (layer 1: Tertiary
and Quaternary Alluvial deposits; layer 2: medium dense organic silt,
sandysilt and stiff siltyclay; layer 3: dense sand; layer 4: silt; layer 5:
medium dense to dense siltysand and sand with some organic matter;
layer 6: dense silty sand and sand; layer 7: soft or loose sandy silt or
silty sand with organic matter; layer 8: soft organic silt; and layer 9:
abutment fill..............................................................................................31
Fig.3.8: Shearwavevelocityprofileat HBMC Bridgesite...................................32
Fig.3.9: Secondretrofit scheme..............................................................................34
Fig.4.1: Uniform hazardspectraoftheHBMC Bridgesite...................................40
Fig.4.2: Seismichazard curves of theHBMC Bridgesite.....................................40
viii
Fig.4.3: Deaggregation of seismic hazard of Humboldt Bay site at 10% in 50
years hazard level andperiod0.5sec.........................................................43
Fig.4.4: Deaggregation of seismic hazard of Humboldt Bay site at 10% in 50
years hazard level and period1.0sec.........................................................44
Fig.4.5: Deaggregation of seismic hazard of Humboldt Bay site at 10% in 50
years hazard level and period2.0sec.........................................................45
Fig.4.6: Spectral acceleration of scaled ground motions at the three seismic
hazard levels..............................................................................................54
Fig.5.1: OpenSees finite element model of HBMC Bridge ground system
(based on blue prints courtesy of Caltrans, mesh constructed using
GIDsoftware)...........................................................................................61
Fig.5.2: Pressureindependent soil material............................................................63
Fig.5.3: Pressuredependent soil material...............................................................65
Fig.5.4: Fiberdiscretizationofpiers cross-section.................................................70
Fig.5.5: Uni-axial cyclic Kent-Park-Scott concretemodel....................................70
Fig.5.6: Uni-axial bilinearsteel model...................................................................70
Fig.5.7: Cyclic moment-curvature response of fiber-section at 4 upper G-L
points ofpierelements..............................................................................71
Fig.5.8: Uni-axial hysteretic model for reinforcing steel at the base cross-
sectionofthebridgepiers.........................................................................71
Fig.5.9: Simulatedcyclicbasemoment-curvatureresponseoflapsplicedpier....72
Fig.5.10: Moment-curvature responses at four lower G-L points of cantilever
bridge pier subjected to quasi-static monotonic pushover (G-L points
numberedfrom bottom totopofpier)......................................................72
Fig.5.11: Fiber discretization of the pile group cross-sections (the piles in the
sameellipsearelumpedintooneequivalent pile)....................................74
Fig.5.12: Shearkeyat abutment joints: (a)as built,and(b)finiteelement model..76
ix