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Rte. 123 Bridge over Occoquan RiverFairfax and Prince William Counties, Virginia

Rte. 123 Bridge over Occoquan RiverFairfax and Prince William Counties, Virginia

m o f f a t t & n i c h o l

T. Michael Harris, P.E.Moffatt & Nichol

Richmond, Virginia

Creative People – Practical Solutions

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Rte. 123 Bridge over the Occoquan RiverRte. 123 Bridge over the Occoquan RiverProject Background

LocationSite CharacteristicsBridge Requirements

Concept DevelopmentPublic InvolvementAesthetics

Final Bridge DesignSubstructure Superstructure

ConstructionConclusion

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Project BackgroundProject BackgroundLocation

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Project BackgroundProject BackgroundTown of Occoquan

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Project BackgroundProject BackgroundTown of Occoquan

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Project BackgroundProject BackgroundSite Characteristics

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Project BackgroundProject BackgroundExisting Bridge

10 Spans – 120’ Steel Plate Girders3 Traffic Lanes (1 NBL & 2 SBL)Functionally ObsoleteSpans Mill St., Parking Lot & Occoquan River

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentProposed Bridge Requirements

7 Traffic Lanes (3 NBL, 3 SBL & 1 SBL Turn)Appropriate Shoulder Widths for SafetyPedestrian WalkwayRaise Profile of the Roadway and BridgeUse Existing Bridge Alignment & ROWParking Area during and after construction Functional and Economical Bridge SolutionApproval of Bridge Concept by Town

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentConcept Study

Bridge Selection CommitteeCitizens and Elected Officials from Town of Occoquan, Fairfax and Prince William CountiesProvide community input into the bridge selection process

Public Involvement

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept Development

EducationBridge TypesPurpose & ApplicationsCost

Public Involvement

Bridge Type Avg. Cost / SFSuspension &

Cable Stay $325

Tied-Arch $275

Classical Arch $225

Modern Arch $175

Box Girder $155

Girder $95

Road

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MO

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Sta

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nsid

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ions

Proj

ect C

ost

LEGEND

Very Good Good Acceptable Poor Very Poor

LEGEND

Very Good Good Acceptable Poor Very Poor

Evaluation SummaryEvaluation Summary

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentPublic Involvement

Approved Bridge Concept

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentPublic Involvement

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentPublic Involvement

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentPublic Involvement

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentBrickwork Formliners

Bases of Pier ColumnsBase of Abutment A MSE Wall

VDOT

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentFractured Rib Formliners

Faces of Pier ColumnsFaces of MSE Wall Panels

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Concept DevelopmentConcept DevelopmentPedestrian Walkway

Recessed PanelsPedestals with LightingFRP Railing Panels

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignSequence of Construction

Stage I Construction

Stage II Construction

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignSummary of Concrete Strengths

Beams and Beam SegmentsDeck SlabParapets, Medians & Railing PedestalsPier Caps & ColumnsPier FootingsAbutments & MSE walls

55 MPa (8,000 psi)40 MPa (5,800 psi)30 MPa (4,300 psi)35 MPa (5,100 psi)25 MPa (3,600 psi)25 MPa (3,600 psi)

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignSummary of Reinforcing Steel

All mild reinforcing steel – ASTM A615 Gr. 60MMFX 2 (Stage II Deck Slab Only) -

ASTM A615 Gr. 75

Prestressing Steel - 0.6” ø, Low-RelaxationASTM A416 Gr. 270

Post-tensioning Steel - 0.6” ø, Low-RelaxationASTM A416 Gr. 270

420 MPa (60 ksi)

520 MPa (75 ksi)

1860 MPa (270 ksi)

1860 MPa (270 ksi)

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignAbutments

Single Row of Steel PilesSocketed into RockMSE Walls

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignMSE Walls

Support of Abutment FillsRetaining Wall for SBL Approach

Support for Roadway Fill (Rte 123 & Rte 722)

Reduced ROWGreater than 350’ long (107 m)Maximum Height of 43.5’ (13.25 m)

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignPiers

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignPiers

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignDeck Slab

8.5” (220mm) Slab ThicknessEpoxy Coated Reinforcing Steel (SBL)MMFX 2 Reinforcing Steel (NBL)

VDOT

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignApproach Spans – (144’-4” Each)

Pier 2Pier 1 Pier 3Abut. A

Span A

Pier 4

Span B Span C Span D

4 Simple Spans – 140’ (42.7m) eachMade Continuous for Live Load

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignMain Span Unit – (180’-240’-180’)

Pier 4 Pier 5 Pier 6 Abut. B

End Segment Haunch SegmentDrop-In SegmentHaunch Segment End Segment

2 End Segments – 128’ (39m) each

2 Haunch Segments – 98’ (30m) each

1 Drop-In Segment – 137’ (41.8m)

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignAnalysis and Design Software

Consplice PT by LEAP SoftwareGirder Line AnalysisTime Dependent Analysis

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignGirder Section

Approach SpansStandard VDOT 77” Bulb-T (PCBT-77)

Main Span UnitModified PCBT-77

2” added to top flange thickness(from 4” to 6” thick)

2” added to overall section width(from 7” web to 9” web)

Modified PCBT-77

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignPost-Tensioning Tendons

3 Tendons (T1, T2 & T3)12 – 0.6” Diameter Strands Per Tendon

T1T2T3

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignPost-Tensioning Ducts

3” Diameter HDPE Round Ducts6” (150mm) Vertical Duct Spacing

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignEnd Segment End Block

2310mm 915mm

392mm

560mm

265mm

T1

T2

T3

End Block Elevation

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignHaunch Segments

Variable Web DepthConstant Bottom Bulb ThicknessOverall Depth Varies from 6.58’ (2007mm) to 12.5’(3810mm)

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignGirder Splices

2’ (600mm) Splice LengthLapped & Interlocking Reinforcing SteelWelded Steel Plates

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignGirder Splices

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignErection Sequence

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Final Bridge DesignFinal Bridge DesignErection Sequence

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionSequence of Construction

Eliminate Stage I Demolition of Existing Fascia GirderNon-Parallel Bridges

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionTransverse Deck Cracking

Full Depth Shrinkage CracksFull Width Cracks Spaced at 3’-10’Extent of Cracking Varies with Span Location

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionSealing of Post-Tensioning Ducts

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments – Casting Yard

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments - Testing

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments –

Impact of Duct Size

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Beam Segments – Re-Cast

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConstructionConstructionWeb Cracking of Approach Girders

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConclusionConclusionNotable and Innovative Features

High Strength Concrete in SuperstructureSpliced and Post-tensioned Bulb-T Girder SegmentsMMFX2 Reinforcing Steel (NBL Deck)FRP RailingsPublic InvolvementCost Effective Aesthetic Features

Formliners for RusticationRecessed PanelsStamped Concrete

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConclusionConclusionApplication of state-of-the-art technology with cost effective architectural enhancements to provide a bridge structure that meets requirements of function and overall aesthetic goals.

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConclusionConclusionComparison

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConclusionConclusionComparison

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Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

ConclusionConclusionComparison

Rte. 123 Bridge over the Occoquan RiverVirginia Concrete Conference 2007

Rte 123 Bridge over the Occoquan RiverRte 123 Bridge over the Occoquan River