Bridge Types DiscussionBridge Types Discussion

January 16, 2008 Task Force Meeting

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What do we want to accomplish?

Review the type of bridges appropriate for project

Examples

Cost ranges

Discuss staff’s preliminary recommendation

Gather Task Force feedback

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Bridge Types for the EIS

Why now?

Need to study impacts of the alternatives – including bridge types – in the EIS document

Impacts of bridge types includeNatural Resource (location/number of piers in water and land)

Aesthetics (visual impact)

Cost

Desirable to study more than one type in EIS document

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Bridge Type vs. Bridge Design

Bridge types are defined by the general form of their load carrying structure. Selection of a bridge type establishes the overall shape and character of the bridge.

Bridge design establishes the size, shape and proportion of the bridge elements based on engineering requirements and aesthetic goals.

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Bridge Types for the EIS

Things to be considered now

Bridge type

Things to be considered later (after the EIS)

Design of aesthetic elements such as lighting, railings, facade treatments

Design of bridge and street connections into the neighborhood

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Three Corridors for the EIS

3. Existing Bridges (no new bridge type)

1. White 2. Yellow

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Bridge Type Attributes/Considerations

Aesthetics:

View of the bridge (viewsheds)

Character of the bridge

Engineering Criteria:

Span lengths

Geometry/alignment

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Bridge Segments

A new bridge will include:

Main Channel spans (over the river) and

Overland spans (over the floodplain and built environment)

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White Corridor Bridge Segments

Overland Spans (977,000 SF)

Main Channel Spans (183,000 SF)

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Yellow Corridor Bridge Segments

Overland Spans (959,000 SF)

Main Channel Spans (152,000 SF)

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Bridge Type Spectrum

$ $$ $$$

Bea

m/

Gird

er

Arc

h

Sus

pens

ion

Beam/Girder Bridge Examples

top left: Palm Valley – Jacksonville, FL

bottom left: Coast Fork Willamette –Creswell

above: Lower Perry – La Grande

Beam/Girder Bridge Examples

top: 5th Street Bridge - Dayton, Ohio

bottom: Perry Street Bridge - Columbus, Ohio

Beam/Girder Bridge Examples

top left: Center Street Bridge – Salem

bottom left: Marion Street Bridge - Salem

above: Willamette Bridge - Oregon City

Beam/Girder Bridge Examplestop left: Roosevelt Bridge - Stuart, Florida (Precast Segmental

Post-Tensioned Box Girder)

middle left and right: Wabasha Bridge - St. Paul, Minnesota (Cast-in-Place Segmental Post-Tensioned Box Girder)

bottom left: Abernethy Bridge - Oregon City (Steel Tub Girder)

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$ $$ $$$

Bea

m/

Gird

er

Beam/Girder Bridge Types

Bridge Type Normal Span Range

Cost Range / sq.ft

Concrete GirderPrecast Prestressed Girder 50' - 180' $100-160

Post-Tensioned Girder 180' - 300' $120-200

Segmental Girder 180' - 750' $200-450

Steel GirderSteel Girder 100' - 400' $120-250

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Costs in Relation to Salem River Crossing Project Cost Estimates

Main Channel Spans (longer spans are needed)$400 per square foot (150,000 – 180,000 sf)

Candidate bridge types: Concrete Segmental Girder or Steel Girder

Overland Spans (shorter spans ok)$250 per square foot – east side (210,000 – 230,000 sf)

$150 per square foot – west side (744,000 – 750,000 sf)

Candidate bridge types: Precast Prestressed Girder or Post tensioned Girder

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What about Arch or Suspension?

$ $$ $$$

Bea

m/

Gird

er

Arc

h

Sus

pens

ion

Arch Bridge Examples

top: Sauvie Island Bridge –Portland, Oregon (Through-Tied Arch)

middle: Troup-Howell Bridge -Rochester, New York (Through-Tied Arch)

bottom: Lake Street Bridge -Minneapolis (Deck Arch)

Arch Bridge Examples

top left: Blennerhassett – West Virginia

bottom left: Gateway Boulevard - Nashville (Partial Through Arch)

below: Page Avenue - Missouri

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Arc

h$ $$ $$$

Arch Bridge

Bridge Type Normal Span Range Cost Range / sq.ft

Arch 150' - 900' $300-600

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Susp

ensi

on

Suspension Bridge Types

Two sub-categories

Full SuspensionDeck held up by cables suspended from cables (Golden Gate)

Cable-Stayed

Deck held up directly from cables supported by piers

$ $$ $$$

Cable-Stayed Bridge Examples

top left: U.S. Grant Bridge - Portsmouth, Ohio (Steel Edge Girders w/ Double Plane of Stays)

middle left: William Harsha Bridge - Maysville, Kentucky (Concrete Edge Girders w/ Double Plane of Stays)

bottom left: East Huntington Bridge - Huntington, West Virginia (Single Pylon Asymmetric)

below: Sunshine Skyway Bridge - St. Petersburg, Florida (Concrete Box Girder w/ Single Plane of Stays)

Hybrid Cable-Stayed/Girder Bridge

Odawara Blueway Bridge – Japan (Extradose Concrete Box Girder)

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Susp

ensi

on$ $$ $$$

Bridge Type Normal Span Range Cost Range / sq.ftCable Stayed 350' -1500' $ 350-600

Extradose Concrete Box Girder 300' - 900' none built in US

Cable Stayed Bridge

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Bridge Type not Considered

Truss Bridge

Older type not commonly used today due to maintenance costs and other issues

More typical for double-deck bridge (such as MarquamBridge in Portland)

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Preliminary Staff Recommendations

Main Channel Spans- Concrete Segmental Girder and Steel Girder- Through Arch?- Deck Arch?

Overland Spans - Precast Prestressed Girder and Post Tensioned

Girder