SR 167 Puyallup River Bridge Replacement
WSDOT/City of Puyallup/Jacobs
The American Council of Engineering Companies (ACEC) of Washington awarded us a 2016 Engineering Excellence Silver Award in the complexity category for this project.
Design-Build Project. Hart Crowser was the geotechnical engineer of record for the design-build team working with WSDOT and the City of Puyallup as co-owners to replace an existing steel truss bridge with a new steel bridge.
High-Capacity Deep Drilled Shaft Foundations. The drilled shafts for the bridge were some of the largest and deepest constructed shafts for a bridge structure in the history of WSDOT. The soils are soft and variable and are predicted to lose significant strength during a seismic event which causes increased vertical loads as well as slope instability at the abutments. The new structure has been designed using large-diameter high-capacity deep drilled shaft foundations to overcome the increased vertical and lateral loads while eliminating both in-water foundation construction and any ground improvement measures for lateral stability. The large-diameter drilled shafts also easily meet the challenges of severe 100- and 500-year flood event scour depths, which are predicted to extend to nearly 25 feet below existing grade, and the significant artesian water conditions present at depth.
State-of-the Art Seismic Design for Unstable Slopes. Abutments at both ends sit atop alluvial flood-plain deposits that create seismically unstable slopes. The abutment foundations are underlain by hundreds of feet of soils susceptible to strength loss during a seismic event, which will transmit extremely large lateral loads to the abutment and intermediate pier foundations. We championed the use of the latest state-of-the-art design procedures which eliminated several grossly conservative design methods to save the owner, and ultimately the taxpayers, hundreds of thousands of dollars.
Sustainability Measures. Reusing the existing steel truss bridge as the temporary detour bridge by rolling it onto adjacent temporary bridge piers and abutments cut months off the proposed construction schedule and eliminated several high risk retaining walls from the project scope.