Optimized Risk in ABC Projects

SH 114 Signature Bridge

Irving, Texas

Matt Paggioli, Webber, LLCSam Piland, Webber, LLC

DFWInternational

Airport

Dallas

Irving

Project Location

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• Bid Date: June 7, 2017

• Completion Date: December 2020

• Client: TxDOT, Dallas District

• Project Award Amount: $39,547,700

SH 114 Signature Bridge

• Scope of Work: Five new bridges over SH 114

• Three vehicular bridges over main lanes and frontage roads

• Two pedestrian bridges over main lanes

• Aesthetic steel truss supported by cable-stay system and

pylons

• New exit ramps and frontage roads

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Project Specifics

• Three vehicular bridges over tolled express lanes, main lanes and frontage roads

• Super structure designed with standard prestressed concrete U-beams and slab

• Two pedestrian bridges over tolled express lanes and main lanes

• Super structure designed as post-tensioned continuous box girder sections utilizing cast-in-place construction methods

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TxDOT requested to open the new tolled express lanes early, but how?

• Webber proposed an ABC method to eliminate the shoring necessary for the pedestrian bridge box girder spans to be cast-in-place and allow the early opening.

• Webber had concerns for additional costs that the original pricing of the work would not cover the proposed ABC method.

So why ABC for this Project?

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City of Irving PropertyLeased to TxDOTApproximately 80 Ac.

• Redesign of post tensioned box girder spans

• Approval process

• Casting location

• Erection of box sections

• Optional traffic routes

• Frontage Road access requirements

• Previous experience

Considerations

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1. Safety Measures• Engineering controls• Traffic control

2. Multiple Professional Engineers (7 Firms) working on the design• DECON – Hired by Webber for multiple design scopes

• Redesign box girders• Geotechnical report on casting yard and travel path• Overhang design

• Mammoet – Heavy lift contractor used in house engineering staff to design the lifts• Webber – Coordinate design and review with in-house engineering services• Toroja – Independent final review of complete design package• TxDOT – Bridge Division review of complete redesign package• PERI Formworks – Design and manufacture of formwork• Structural Technologies (VSL) – Design and install of post tensioned system

3. Survey Control

Risk Management Strategies

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Shoring occupying express lanes for 8 months to cast all four spans

Express Lane

Risk Management Strategies

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• First ABC method considered. Cast box girder spans on existing newly constructed bridge and utilize sliding jack method for moving to final location• Ruled out due to risk associated with excessive loading on newly constructed bridge

Precast Box Girder SpansFirst Option Considered

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• Post tensioned box girder spans cast off site on the ground with steel lifting girders in place

Precast Box Girder SpansSecond Option Considered

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• Staging area location and transporting route

Precast Box Girder SpansSecond Option Considered

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Precast Box Girder SpansReinforcing Section Views

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Precast Box Girder Span Forming System

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Precast Box Girder SpansPost Tension Tendon Location

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Precast Box Girder SpansClosure Pour At Center Bents

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Gantry Arrangement for Lifting Box Girder Spans

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Precast Box Girder SpansTransport Plan

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Precast Box Girder SpansPouring Top Phase

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Completion of Casting Precast Box Girder Spans at Staging Area

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Precast Box Girder SpanLifted and Loaded on SPMT

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Precast Box Girder SpanTransported with SPMT

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Precast Box Girder SpanAdjustments with SPMT

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Precast Box Girder SpanBeing Set in Place

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Precast Box Girder SpanInstalled

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https://youtu.be/JxlxVwU21xQ

Transporting and Installation with SPMT

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Thank You

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Questions?

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