Tanana River Bridge

CLIENT Alaska Railroad Corportation

Location Salcha, AK

Shannon & Wilson performed the site exploration, engineering, and construction observation studies for the design and construction of a 3,300-foot rail bridge. 

The bridge included 19 piers, each supported by four 72-inch diameter piles, and each abutment supported by twenty-two 24-inch diameter piles. 

The project included additional bridges across three sloughs, railroad bed and approach embankments, roads, and geotechnical explorations and pumping tests for the design of nearly two miles of levee/river training structures. Sixty-eight exploratory borings were advanced up to 150 feet deep and required permitting and ice road/bridge construction across the Tanana River to provide access. Design of the pier piles required coordination with the design team and contractor to assess foundation options, constructability, and design issues.  The bridge lies on the Salcha seismic zone and studies were conducted to assess the sites liquefaction and lateral spreading hazards and ice and debris impacts on the bridge pile foundations. 

Services included multiple task orders over a period of several years to assess subsurface conditions at potential crossing alignments.  Multiple foundation design/construction scenarios were assessed; CM/GC involvement required analysis of alternate concepts; selected design concept proceeded forward to design development and construction. The large pile diameter was new to interior Alaska and no previous similar pile had been performed.  Funding limitations eliminated pre-construction pile load testing and we were involved through construction to assess and refine pile capacities based on driving resistance and dynamic pile testing. Design objectives were achieved, bridge abutment and pier pile foundations were installed as designed and met required axial resistances.


Steve Adamczak
Vice President

Christopher Darrah
Vice President, Fairbanks Office Manager

Oliver Hoopes
Senior Associate

Mark Lockwood
Senior Associate

Wendy Mathieson
Vice President

Bill Perkins
Vice President, Earthquake Engineering Services

Kathryn Petek
Vice President

Wendy Presler
Senior Associate

Hisham Sarieddine
Vice President

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