Investigation of the Seismic Response of Slender Concrete ... - PEER

Experimental TestingOf Planar Walls

ConvenXonalWallTesXngTest of High-Rise Core Wall: EffectiveStiffness for Seismic Analysis by P.Adebar, AM.M. Ibrahim and M. Bryson, 2008DamageMeasuredResponse

NEESExperimentalTesXngatUIUC• BoOomthreestoriesof10‐storyplanarprototypewall.• ShearandmomentappliedtosimulatelateralloaddistribuXonin10‐storyprototype• Targetaxialloadof0.1A g f c ’.

NEESExperimentalTesXngatUIUC• PrimaryloadingviatwoLBCBs• Axialload(F z )• Shearload(cyclicallyincreasingΔ x )• Moment(M y =k1*V top )• Floorloadingviauniaxialactuators(V=k*V top ) F zΔ xM y = k1*V topk2*V topk3*V top

PlanarWallTestSpecimens• 1/3‐scalewithdetailsreflecXngmodernconstrucXonpracXce.BOUNDARYELEMENTS(3.5%)12’HEIGHT18in.THICK(4’/6in.LAB)SPLICEATBASEOFWALL

PlanarWallTestMatrixMoment-toShear RatioDistribution ofReinforcementSplices?STUDYPARAMETERSWall 1M b = 0.71hV bV b = 2.8√f ’c = 0.7V nBE at EDGEYESWall 2M b = 0.50hV bV b = 4.0√f ’c = 0.9V nBE at EDGEYESWall 3M b = 0.50hV bV b = 4.0√f ’c = 0.9V nUNIFORMYESWall 4M b = 0.50hV bV b = 4.0√f ’c = 0.9V nBE at EDGENO

FinalDamageStatesforPlanarWallsWall 1: V b = 3.6√f’c1.5% drift (3 rd story)2.1% drift (10 th story)Wall 2: : V b = 5.0√f’c1.5% drift (3 rd story)1.8% drift (10 th story)Wall 3: V b = 4.5√f’c1.25% drift (3 rd story)1.6% drift (10 th story)Wall 4: V b = 4.6√f’c1.0% drift (3 rd story)1.4% drift (10 th story)

InstrumentaXonforMonitoringLocalResponse

Wall4DisplacementMeasuredUsingMetrisSystem

Wall4ShearDeformaXonfromMetrisData

KryptonandDisp.TransducerDataWall 1 Wall 23 rd floor shear2 nd floor shear1 st floor shear3 rd floor flexural2 nd floor flexural1 st floor flexuralBase rotationBase slipContribution to total drift (%)Contribution to total drift (%)Wall 3 Wall 4Drift at top of specimenDrift at top of specimen

Experimental Testingof Coupled Walls

ExperimentalTestProgram• Prototypestructure• ExperimentaltestmatrixCore Wall under Construction(Courtesy of MKA, Seattle)

WhatistheSeismicBehaviorofaModernCoupledWall?• Reviewinventoryofmoderncoupledwalls– 17buildingswithcoupled‐corewallsystemsdesignedforconstrucXoninCAorWAinlast10years.– InformaXoncollectedincludedgeometry,aspectraXos,reinforcementraXos,degreeofcoupling,sheardemand‐capacityraXo,pierwallaxialdemand‐capacityraXo,etc.• Reviewpreviousexperimentaltests– Numeroustestsofcouplingbeamswithdifferentreinforcementlayouts,raXosandconfinementdetails.– Fewcoupled‐wallstests.– CoupledwalltestspecimenswerenotrepresentaXveofcurrentdesignpracXces.• DesignandevaluatemulXple10‐storyplanarcoupledwalls– DesignwallsfollowingtherecommendaXonsoftheSEAOCSeismicDesignManual,Vol.III,usingASCE7‐05,andmeeXngrequirementsofACI318‐08.– ProgressionofyieldingandfailuremechanismwasevaluatedviaconXnuumfiniteelementanalysisusingVecTor2

CoupledWallTestSpecimen• SpecimenisboOomthreestoriesofa10‐storyplanarcoupledwall.• CouplingbeamshaveaspectraXoof2.0anddiagonalreinforcement.• Seismicloadingresultsinyieldingincouplingbeamsandwallpiers.• Pierwallsarecapacity‐designedforshearinwallpiers.Boundary Element• ρ long = 3.5%• ρ trans = 1.4%Web• ρ long = 0.27%• ρ horz = 0.27%Coupling beams:• aspect ratio = 2.0• ρ diag = 1.25%• V n =

ConstrucXon

LoadingProtocolDevelopment• EachpierhassixDegreesofFreedomtocontrol– OnetranslaXonandtworotaXonssettozero– TwotranslaXonsandoutofplanerotaXonacXve

LoadingProtocolDevelopment• SpecimenhassixacXveDOFs• Totalaxialloadconstant• ∆ x prescribedfordisplacementcontrol• TotalbendingmomentattopofspecimencalculatedfromassumedlateralloaddistribuXon• SixDOFs• ∆ x1 independentinput• 2force‐basedconstraintequaXons• Require3addiXonalequaXonstoaccomplishtesXng

LoadingProtocolDevelopment• Analysesof10‐storywallusingVecTor2conXnuummodel– MonotonicloadingwithprescribedloaddistribuXon– CyclicloadingwithprescribedeffecXveheight• DisplacementandrotaXonsattopofthirdfloormonitored. • Results:∆ x1 ≈∆ x2θ y1 ≈θ y2 ≈α∆ x

LoadingProtocolDevelopment• LoadingprotocolvalidatedbycomparingcrackpaOersandstressfieldsin10‐storywallwiththosein3‐storyspecimenwith∆ x1 =∆ x2 =βθ y1 =β θ y2

LoadingProtocolDevelopment• θ y forbothpierssetasmulXpleof∆ x • RelaXonsaresetforcontrolofthesixacXveDOFs:– F z1 +F z2 =constant– ∆ x1 =∆ x2 =∆ x– M y,total =k*(F x1 +F x2 )– θ y1 =θ y2 =n*∆ x

TesXngofCoupledWall

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