Secant Pile Construction

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1 Secant Pile Construction OSIS Augmentation & Relief Sewer (OARS) Phase 2 Shafts # 3, 4 & 5 DFI – ADSC Drilled Shaft Seminar Support with Confidence July 11-12, 2013 Secant Piles Construction Structural foundation element consisting of overlapping piles forming a continuous wall. Reinforced concrete (rebar cages or soldier piles). Depth depends upon final design & soil and equipment characteristics. Piles diameters usually based on metric tooling size. Typically 760, 880, 1000 and 1180 mm are used. Other sizes are available. Secant piles walls to be cantilevered or braced. Any geometric shape is possible. The more unique the shape the more difficult the bracing system becomes.

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Secant Pile Construction

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