Performance of 18-Story Steel Moment-Frame Buildings During a Large San Andreas Earthquake

177 Pages·2012·12.62 MB·English

EERL2005-01
EarthquakeEngineering
ResearchLaboratory
Performance of 18-Story Steel Moment-Frame Buildings During a Large
San Andreas Earthquake (cid:150) A Southern California-Wide End-to-End
Simulation
by
SwaminathanKrishnan,ChenJi,DimitriKomatitsch,andJeroenTromp
Thisstudywasconductedatthe
SeismologicalLaboratory
N S TITUTE OF
A I TE
NI CH
R N
O 1891 O
F L
I O
L G
AC Y
CaliforniaInstituteofTechnology
Pasadena,California
2005
ii
(cid:13)c 2005
SwaminathanKrishnan,ChenJi,DimitriKomatitsch,andJeroenTromp
AllRightsReserved
iii
Acknowledgements
WewishtogratefullyacknowledgethefundingprovidedbytheSeismologicalLaboratoryattheCaliforniaInstitute
ofTechnology.WealsowishtothankProfessorsJohnF.Hall,ThomasHeaton,andHirooKanamorioftheCalifornia
InstituteofTechnologyfortheirinsightsandadviceduringthecourseofthisstudy. Thenumericalsimulationswere
performedontheDivisionofGeological&PlanetarySciencesDellclusterattheCaliforniaInstituteofTechnology,
USA,andtheSeawulfclusterattheUniversityofToronto,Canada.
iv
Summary
ThemitigationofseismicriskinurbanareasintheUnitedStatesandabroadisofmajorconcernforallgovernments.
Unfortunatelynocomprehensivestudieshaveattemptedtoaddressthisissueinarigorous,quantitativemanner. This
study tackles this problemhead-on for two 18-storysteel moment-framebuildings in southern California. The ap-
proachadoptedherecan beusedas atemplate tostudyearthquakeriskinotherseismicallysensitiveregionsofthe
world,suchasTaiwan,Japan,Indonesia,China,SouthAmericancountries(Chile,Bolivia,etc.),andthewestcoastof
theUnitedStates(inparticular,Seattle).
In 1857 a large earthquake of magnitude 7.9 [1] occurred on the San Andreas fault with rupture initiating at
Park(cid:2)eld in Central California and propagating in a southeasterly direction over a distance of more than 360 km.
Suchaunilateralruptureproducessigni(cid:2)cantdirectivitytowardtheSan FernandoandLosAngelesbasins. Indeed,
newspaperreports(LosAngelesStar[2,3])ofsloshingobservedintheLosAngelesriverpointtolong-duration(1(cid:150)2
min)andlong-period(2(cid:150)8s)shakingwhichcouldhaveasevereimpactonpresent-daytallbuildings,especiallyinthe
mid-heightrange.Toassesstheriskposingthetwosteelmoment-framebuildingsfroman1857-likeearthquakeonthe
SanAndreasfault,a(cid:2)nitesourcemodelofthemagnitude7.9November3,2002Denalifaultearthquakeismappedon
totheSanAndreasfaultwithruptureinitiatingatPark(cid:2)eldinCentralCaliforniaandpropagatingadistanceofabout
290kminasouth-easterlydirection. AstheruptureproceedsdownsouthfromPark(cid:2)eldandhitsthebigbendonthe
SanAndreasfaultitshedsoffasigni(cid:2)cantamountofenergyintotheSanFernandovalley,generatinglargeamplitude
groundmotion there. A good portion of this energyspills over into the Los Angeles basin with many cities along
thecoastsuchasSantaMonicaandSealBeachandmoreinlandareasgoingeastfromSealbeachtowardsAnaheim
experiencinglong-durationshaking.Inaddition,thetail-endoftheruptureshedsenergyfromSH/Lovewavesintothe
SanGabrielvalley(BaldwinPark-LaPuenteregion).Theseseismicwavesgettrappedandampli(cid:2)edinthebasin.The
peakvelocityisoftheorderof1m.s(cid:0)1intheLosAngelesbasin,includingdowntownLosAngeles,and2m.s(cid:0)1inthe
SanFernandovalley. Signi(cid:2)cantdisplacementsoccurinthebasinsbutnotinthemountains. Thepeakdisplacements
are in the neighborhoodof 1 m in the Los Angeles basin and 2 m in the San Fernando valley. The ground motion
simulationisperformedusingthespectralelementmethodbasedseismicwavepropagationprogram,SPECFEM3D.
To study the effects of the ground motion simulated at 636 sites (spread across southern California, spaced at
about 3.5 km each way), computer models of an existing 18-story steel moment-frame building and a redesigned
building with the same con(cid:2)guration (redesigned to current standards using the 1997 Uniform Building Code) are
analyzedusingthenonlinearstructuralanalysisprogram,FRAME3D.Fortheseanalyses,thebuildingYdirectionis
alignedwith the geographicalnorthdirection. As expected, the existing buildingmodel fares much worse than the
redesignedbuildingmodel. Fracture occursin at least 25% of the connectionsin this building whenlocated in the
SanFernandovalley. About10%ofconnectionsfractureinthebuildingwhenlocatedindowntownLosAngelesand
themid-Wilshiredistrict(BeverlyHills),whilethenumbersareabout20%whenitislocatedinSantaMonica,west
LosAngeles,Inglewood,Alhambra,BaldwinPark,LaPuente,Downey,Norwalk,Brea,Fullerton,AnaheimandSeal
Beach. Thepeakinterstorydriftsinthemiddle-thirdandbottom-thirdoftheexistingbuildingarefargreaterthanthe
top-thirdpointingtodamagebeinglocalizedtothelower(cid:3)oors. Thelocalizationofdamageinthelower(cid:3)oorsrather
thantheupper(cid:3)oorscouldpotentiallybeworsebecauseoftheriskofmore(cid:3)oorspancakingontopofeachotherifa
singlestorygivesway. Consistentwiththeextentoffractureobserved,thepeakdriftsintheexistingbuildingexceed
0.10whenlocatedintheSanFernandovalley,BaldwinParkandneighboringcities,SantaMonica,westLosAngeles
andneighboringcities,Norwalkandneighboringcities,andSealBeachandneighboringcities,whichiswellintothe
postulatedcollapseregime.WhenlocatedindowntownLosAngelesandthemid-Wilshiredistrict,thebuildingwould
v
barelysatisfythecollapsepreventioncriteriasetbyFEMA[4]withpeakdriftsofabout0.05.
The performanceof the newly designed 18-storysteel building is signi(cid:2)cantly better than the existing building
fortheentireregion. However,thenewbuildingstillhassigni(cid:2)cantdriftsindicativeofseriousdamagewhenlocated
in the San Fernando valley or the Baldwin Park area. When located in coastal cities (such as Santa Monica, Seal
Beach etc.), the Wilshire-corridor (west Los Angeles, Beverly Hills, etc.), Norwalk and neighboring cities, or the
boomingOrangeCountycitiesofAnaheimandSantaAna,ithaspeakdriftsofabout0.05onceagainbarelysatisfying
the FEMA collapse prevention criteria [5]. In downtown Los Angeles it does not undergo much damage in this
scenario. Thus,eventhoughthisbuildinghasbeendesignedaccordingtothelatestcodeitsuffersdamagethatwould
necessitateclosureforsometimefollowingtheearthquakeinmostareas, butthisshouldbeexpectedsincethisisa
largeearthquakeandbuildingcodesarewrittentolimitthelossoflifeandensure(cid:147)collapseprevention(cid:148)forsuchlarge
earthquakesandnotnecessarilylimitdamage.
AsecondscenarioconsideredinthestudyinvolvesthesameDenaliearthquakesourcemappedtotheSanAndreas
faultbutwithruptureinitiatinginthesouthandpropagatingtothenorth(withthelargestamountofslipoccurringto
thenorthinCentralCalifornia)insteadoftheotherwayaround. Theresultsofsuchascenarioindicatethatground
shakingwouldbefarlessseveredemonstratingtheeffectsofdirectivityandslipdistributionindictatingthelevelof
groundshakingandtheassociateddamageinbuildings. Thepeakdriftsinexistingandredesignedbuildingmodels
areintherangeof0.02(cid:150)0.04indicatingthatthereisnosigni(cid:2)cantdangerofcollapse. However,damagewouldstill
besigni(cid:2)cantenoughtowarrantbuildingclosuresandcompromiselifesafetyinsomeinstances.
Thegroundmotionsimulationandthestructuraldamagemodelingproceduresarevalidatedusingdatafromthe
January17,1994,Northridgeearthquakewhiletheband-limitednatureofthegroundmotionsimulation(limitedto
ashortestperiodof2sbythecurrentstateofknowledgeofthe3-DEarthstructure)isshowntohavenosigni(cid:2)cant
effectontheresponseofthetwotallbuildingsconsideredherewiththeuseofobservedrecordsfromthe1999Chi
ChiearthquakeinTaiwanandthe2001Tokachi-OkiearthquakeinJapan.
vi
Contents
Acknowledgements iii
Summary iv
1 Introduction 1
1.1 ScopeoftheSimulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1.1 ScenariosConsidered. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1.2 BuildingsConsidered. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1.3 End-to-EndSimulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 BuildingDetails 4
2.1 ExistingBuilding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2 Redesigned(New)Building. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 GravityLoadingCriteriafortheTwoBuildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.4 SeismicCriteriafortheDesignoftheNewBuilding . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.5 WindCriteriafortheDesignoftheNewBuilding . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.6 DesignoftheNewBuildingperUBC97UsingtheCommercialProgramETABS . . . . . . . . . . . 11
2.7 NonlinearAnalysisofBuildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.7.1 AnalysisAssumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.7.2 PushoverAnalysesoftheTwoBuildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3 SoftwareUsedfortheEnd-to-EndSimulations 20
3.1 SPECFEM3D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.2 FRAME3D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4 LimitationsoftheStudy 23
5 ValidationUsingtheNorthridgeEarthquakeData 25
6 EffectofFilteringRecordsonBuildingAnalyses 32
7 PastEarthquakesontheSanAndreasFault 37
8 SourceModelUsedintheSimulationoftheMagnitude7.9EarthquakesontheSanAndreasFault 38
9 Scenario1:North-to-SouthRuptureoftheSanAndreasFault 44
10 Scenario2:South-to-NorthRuptureoftheSanAndreasFault 58
11 Conclusions 70
12 FutureResearch 72
vii
A SectionDatabase 73
B ExistingBuildingFrameElevationsandBeamandColumnSizes 74
C RedesignedBuildingFrameElevationsandBeamandColumnSizes 81
D Scenario1(North-to-SouthRupture): PerformanceofExistingandRedesignedBuildingModelsBased
onPlasticRotationsinBeamsandPanelZones 91
E Scenario2(South-to-NorthRupture): PerformanceofExistingandRedesignedBuildingModelsBased
onPlasticRotationsinBeamsandPanelZones 95
F DetailsofthePerformanceofExistingandRedesignedBuildingModelsin8SouthernCalifornianCities 99
F.1 Site: ThousandOaks(Latitude34.18750,Longitude118.87500) . . . . . . . . . . . . . . . . . . . . 100
F.1.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
F.1.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
F.2 Site: Northridge(Latitude34.21875,Longitude118.53125). . . . . . . . . . . . . . . . . . . . . . . 107
F.2.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
F.2.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
F.3 Site: WestLosAngeles(Latitude34.03125,Longitude118.40625) . . . . . . . . . . . . . . . . . . . 114
F.3.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
F.3.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
F.4 Site: DowntownLosAngeles(Latitude34.06250,Longitude118.25000). . . . . . . . . . . . . . . . 121
F.4.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
F.4.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
F.5 Site: BaldwinPark(Latitude34.09375,Longitude118.00000) . . . . . . . . . . . . . . . . . . . . . 128
F.5.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
F.5.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
F.6 Site: Anaheim(Latitude33.84375,Longitude117.90625). . . . . . . . . . . . . . . . . . . . . . . . 135
F.6.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
F.6.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
F.7 Site: LongBeach(Latitude33.78125,Longitude118.18750) . . . . . . . . . . . . . . . . . . . . . . 142
F.7.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
F.7.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
F.8 Site: SantaAna(Latitude33.75000,Longitude117.87500) . . . . . . . . . . . . . . . . . . . . . . . 149
F.8.1 ExistingBuildingPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
F.8.2 RedesignedBuildingPerformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
viii
List of Figures
1.1 Geographicalscopeofthesimulation(Thecolorschemere(cid:3)ectstopography,withgreendenotinglow
elevation and yellow denoting mountains): The solid black triangles denote the 636 sites at which
seismogramsarecomputedandbuildingsareanalyzed.Thewhiteboxisthesurfaceprojectionofthe
Northridgefault.Theredlineintheinsetisthesurfacetraceofthe290kmruptureoftheSanAndreas
faultthatistheprimaryfocusofthisstudy. Theareaenclosedbythebluepolygondenotestheregion
coveredbythe636sites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Structural models of buildings studied: [A] Perspective view of existing building (designed using
codespriortothe1997UniformBuildingCode). [B]Perspectiveviewofredesigned(new)building
(redesignedusingthe1997UniformBuildingCode). . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Plans oftheexistingbuildingshowingthelocationofcolumnsandmoment-frame(MF)beams(the
frameelevationswithbeamandcolumnsizesaregiveninAppendixB). . . . . . . . . . . . . . . . . 6
2.3 Plansoftheredesignedbuildingshowingthelocationofcolumnsandmoment-frame(MF)beams(the
frameelevationswithbeamandcolumnsizesaregiveninAppendixC). Notethegreaternumberof
moment-framebaysintheredesignedbuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4 The 1997UniformBuildingCoderesponsespectrumusedin thedesignofthe newbuilding(C =
a
0:48andC =0:64). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
v
2.5 Pushoveranalysisoftheexistingandtheredesignedbuildings: (A)Xdirectionpushover(cid:150)roofdis-
placementversusbaseshear.(B)Xdirectionpushover(cid:150)baseshear(solidlines)androofdisplacements
(dashedlines)asfunctionsoftime. (C)Ydirectionpushover(cid:150)roofdisplacementversusbaseshear.
(D)Ydirectionpushover(cid:150)baseshear(solidlines)androofdisplacements(dashedlines)asfunctions
oftime. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.1 Elementarrangementinframemodelshowingjointnodes,attachmentpoints,localbeamnodesand
coordinatesystems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.1 SlipmodelfortheJanuary17,1994,magnitude6.7Northridgeearthquakedeterminedusingawavelet
transformapproach. Theredstardenotesthehypocenterandthewhitearrowsdenotetheslipvector.
Thedipangleofthefaultis40degrees(seeFigure1.1forthesurfaceprojectionofthefault) . . . . . 25
5.2 Northridgesimulation(cid:150)Dataversussyntheticseismograms: (A)nearbystationsnorthoftherupture;
(B)distantstations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.3 Northridge validation (cid:150) analysis of existing building in Woodland Hills subjected to Oxnard Blvd.
record(WHOX):Measured18th(cid:3)oor(A)N-Sand(B)E-Wdisplacementsversuscorrespondingcom-
puteddisplacements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.4 AnalysisoftheexistingbuildingsubjectedtotheOxnardBoulevard,WoodlandHills(WHOX)record
fromNorthridgeearthquake(stationlocated0.5milefromthebuilding): Observedconnectionfrac-
tures(squares)versussimulatedfractures(solidtriangles)(cid:150)(A)Southmoment-frame(alonggridA,
east-westdirection)ofthebuilding(Frame1); (B)Northmoment-frame(alonggridD,east-westdi-
rection) of the building(Frame 4); (C) West moment-frame(alonggrid 1, north-southdirection)of
thebuilding(Frame6); (D)Eastmoment-frame(alonggrid6,north-southdirection)ofthebuilding
(Frame7). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
ix
5.5 Comparisonofthehorizontalcomponentsofvelocityofthreerecordsfromthe1994Northridgeearth-
quake,SATI,CNPK,andWHOX(Source:URSCorporation). . . . . . . . . . . . . . . . . . . . . . 30
5.6 Permanentoffsetsonthefourfacesoftheexistingbuildingmodel(penthouseplanshownhere)com-
putedusingtheWHOXrecordfromtheNorthridgeearthquake.. . . . . . . . . . . . . . . . . . . . . 31
6.1 Pseudo-accelerationresponsespectraofrecords(northcomponent)fromtheChi-ChiandTokachi-Oki
earthquakes:Comparisonofspectraofun(cid:2)ltered(solid)and(cid:2)ltered(dashed)records. . . . . . . . . . 33
6.2 Pseudo-accelerationresponsespectraofrecords(eastcomponent)fromtheChi-ChiandTokachi-Oki
earthquakes:Comparisonofspectraofun(cid:2)ltered(solid)and(cid:2)ltered(dashed)records. . . . . . . . . . 34
6.3 Peakdriftsobservedintheexistingbuilding(cid:150)analysesusing(cid:2)lteredandun(cid:2)lteredrecords.Pencolors
usedtoplotthepointsmatchthoseusedinFigures6.1and6.2. . . . . . . . . . . . . . . . . . . . . . 35
6.4 Peakdriftsobservedintheredesignedbuilding(cid:150)analysesusing(cid:2)ltered andun(cid:2)lteredrecords. Pen
colorsusedtoplotthepointsmatchthoseusedinFigures6.1and6.2. . . . . . . . . . . . . . . . . . 36
8.1 Slip distribution of the 2002 Denali earthquake constrained by teleseismic body and strong motion
waveformsaswellasGPSvectors. Thecolorschemere(cid:3)ectstheslipamplitudeandcontoursre(cid:3)ect
theruptureinitiationtime. Thehypocenterisindicatedbytheredstar. Whitearrowsdenotetheslip
directionandmagnitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
8.2 Surfaceslip,particlevelocity,andrupturetime,forthesimulatedmagnitude7.9earthquakeontheSan
Andreasfault(cid:150)north-to-southrupture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
8.3 Surfaceslip,particlevelocity,andrupturetime,forthesimulatedmagnitude7.9earthquakeontheSan
Andreasfault(cid:150)north-to-southrupture,cappedparticlevelocitycase. . . . . . . . . . . . . . . . . . . 40
8.4 1999ChiChiearthquake:Peakgroundvelocities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.5 Denalisourceinversion: Data(black)versussyntheticseismograms(red)forPumpStation10(3km
fromthefaulttrace). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.1 M 7:9earthquake(north-to-southrupture)ontheSanAndreasFault(cid:150)groundshaking: Mapofpeak
w
velocities(eastcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
9.2 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
velocities(northcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9.3 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
velocities(verticalcomponent).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9.4 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(eastcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
9.5 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(northcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
9.6 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(verticalcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.7 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Peakdriftratiosinthetop-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.8 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Peakdriftratiosinthemiddle-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.9 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Peakdriftratiosinthebottom-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.10 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Peakdriftratiosanywhereinthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
x
9.11 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Permanentoffsetatthepenthouselevel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.12 M 7:9earthquake(north-to-southrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Percentageofconnectionsthat fracture(outofatotalof710 connectionswiththetwo endsofeach
moment-framebeamandcolumnde(cid:2)nedasconnections).. . . . . . . . . . . . . . . . . . . . . . . . 54
9.13 M 7:9 earthquake (north-to-southrupture) on the San Andreas fault (cid:150) redesigned building perfor-
w
mance: Peakdriftratiosinthetop-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.14 M 7:9 earthquake (north-to-southrupture) on the San Andreas fault (cid:150) redesigned building perfor-
w
mance: Peakdriftratiosinthemiddle-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . 55
9.15 M 7:9 earthquake (north-to-southrupture) on the San Andreas fault (cid:150) redesigned building perfor-
w
mance: Peakdriftratiosinthebottom-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . 56
9.16 M 7:9earthquake(north-to-southrupture)ontheSan Andreasfault(cid:150)RedesignedBuildingPerfor-
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mance: Peakdriftratiosanywhereinthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
9.17 M 7:9 earthquake (north-to-southrupture)on the San Andreas Fault (cid:150) redesigned building perfor-
w
mance: Permanentoffsetatthepenthouselevel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
10.1 Surfaceslip,particlevelocity,andrupturetime,forthesimulatedmagnitude7.9earthquakeontheSan
Andreasfault(cid:150)south-to-northrupture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
10.2 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
velocities(eastcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
10.3 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
velocities(northcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
10.4 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
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velocities(verticalcomponent).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
10.5 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(eastcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
10.6 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(northcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
10.7 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)groundshaking: Mapofpeak
w
displacements(verticalcomponent). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
10.8 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
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Peakdriftratiosinthetop-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
10.9 M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
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Peakdriftratiosinthemiddle-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
10.10M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
w
Peakdriftratiosinthebottom-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
10.11M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
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Peakdriftratiosanywhereinthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
10.12M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
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Permanentoffsetatthepenthouselevel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
10.13M 7:9earthquake(south-to-northrupture)ontheSanAndreasfault(cid:150)existingbuildingperformance:
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Percentageofconnectionsthat fracture(outofatotalof710 connectionswiththetwo endsofeach
moment-framebeamandcolumnde(cid:2)nedasconnections).. . . . . . . . . . . . . . . . . . . . . . . . 66
10.14M 7:9 earthquake (south-to-northrupture) on the San Andreas fault (cid:150) redesigned building perfor-
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mance: Peakdriftratiosinthetop-thirdofthebuilding. . . . . . . . . . . . . . . . . . . . . . . . . . 67