Secant Pile Construction
description
Transcript of Secant Pile Construction
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Secant Pile ConstructionOSIS Augmentation & Relief Sewer (OARS) Phase 2 Shafts # 3, 4 & 5
DFI ADSC Drilled Shaft SeminarSupport with Confidence
July 11-12, 2013
SecantPilesConstruction
Structuralfoundationelementconsistingofoverlappingpilesformingacontinuouswall.
Reinforcedconcrete(rebarcagesorsoldierpiles). Depthdependsuponfinaldesign&soilandequipment
characteristics. Pilesdiametersusuallybasedonmetrictoolingsize.Typically
760,880,1000and1180mmareused.Othersizesareavailable.
Secantpileswallstobecantileveredorbraced.Anygeometricshapeispossible.Themoreuniquetheshapethemoredifficultthebracingsystembecomes.
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SecantPilesConstruction
Selectionofsecantpilesvs.otherearthretentionsupportsystemsisbasedon: Availableworkspace/sitelogistics Layoutofwall Impactrestrictionsonadjacentstructures Designparameters(stiffnessofwall,cutoffrequirements)
Materialhandlingrequirements Excavationcapabilitiesindifficultsoilconditions
SecantPilesConstruction
Sequenceofconstruction Guidewallsinstallation Primaryorlaggingpilesinstallation
Sectionalcasingrotationinadvanceofaugerremovingsoilinsideofthecasing
Dryorwetdrillingdependinguponsoilsconditions
Atdrillingcompletion,cleaningofpilebottom&placementofconcrete Freefallplacementindryconditionandwithatremie pipeinwetconditions
Extractionofcasingatpourcompletion Secondaryorclosingpilesinstallation
Sectionalcasingrotationinadvanceofaugerremovingsoilinsideofthecasing
Dryorwetdrillingdependinguponsoilsconditions
Atdrillingcompletion,cleaningofpilebottom&placementofreinforcementfollowedbyconcrete
Freefallplacementindryconditionandwithatremie pipeinwetconditions
Extractionofcasingatpourcompletion
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SecantPilesConstruction
Sequenceofconstruction Guidewallsinstallation
SecantPilesConstruction
Sequenceofconstruction Primaryorlaggingpilesinstallation
Pilestypicallyunreinforced Lowerstrengthconcretecanbeused.Dependentondesignandfinal
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SecantPilesConstruction
Sequenceofconstruction Primaryorlaggingpilesinstallation
Sectionalcasingrotatedaheadofaugercleaninginsideofcasing
SecantPilesConstruction Sequenceofconstruction
Primaryorlaggingpilesinstallation Sectionalcasingrotationaheadofaugercleaninginsideofcasing
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SecantPilesConstruction Sequenceofconstruction
Secondaryorclosingpilesinstallation Pilesarereinforcedusingrebarcagesorsoldierpiles Highstrengthconcreteistypicallyused
Secondary Piles
Primaryiles
SecantPilesConstruction Sequenceofconstruction
Secondaryorclosingpilesinstallation Designmayrequiredallpilestobereinforced,inthatcasethelaggingpileswillbe
pouredusingstructuralconcrete
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SecantPilesConstruction
Sequenceofconstruction Secondaryorclosingpilesinstallation
Pilesoverlapiscriticaltoguaranteecontinuityofwall Overlapisdependingofdepthofdrilledpilesanddrillingverticalitytolerance
SecantPilesConstruction Sequenceofconstruction
Secondaryorclosingpilesinstallation Loadbearingcaissonscanbeeasilyincorporatedintosecantwall
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SecantPilesConstruction
CaseHistory
Project: OSISAugmentation&ReliefSewer(OARS)Phase2Shafts#3,4&5
ProjectInformation: 397Each 1180mmShafts
3independentsiteslocatedapproximatelymilefromeachother
Eachsecantpilewallsystemcomprisedofandropshaftandapproachchannel.
Eachsecantpilefortheaccessshaftwaskeyed5intoshalebedrock.
AverageSecantPileDrillLengthwas62.
OARSPhase2CaseHistory ShaftLocations
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OARSPhase2Project SubsurfaceProfile
DropShafts: SecantPileCompressionRingDesign
All4,500psiConcrete
Noreinforcementrequiredfordesignaslongverticalitytolerancemet,
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OARSPhase2Project Shaft3Layout
85 each Secant Piles @ 53 Long
OARSPhase2Project Shaft4Layout
173 each Secant Piles @ 64 Long
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OARSPhase2Project Shaft5Layout
139 each Secant Piles @ 65 Long
OARSPhase2Project KODENUltrasonicDeviceVerticalityControl
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OARSPhase2Project JeanLutzGyroscopeVerticalityControl
OARSPhase2Project KODENUltrasonicDeviceOutput
Pile #17B:Pile Depth = 57.83ftDeviation in x' direction = .78inDeviation in y direction = 1.57inTotal deviation = 1.75 < 7.08in = accepted
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OARSPhase2ProjectPhotos
OARSPhase2ProjectPhotos
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OARSPhase2ProjectPhotos
OARSPhase2ProjectPhoto
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OARSPhase2ProjectPhoto
OARSPhase2ProjectPhoto
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OARSPhase2ProjectPhoto
QUESTIONS?
SecantPilesConstruction