Project Details
Project Description
This project consisted of replacing the existing 309 foot long timber truss bridge on Pearl Hill Road spanning Foster Creek near the Chief Joseph Dam in Bridgeport, Washington. The existing bridge had a weight limit imposed on it. Allowing only a single car on the bridge at one time, and forcing larger vehicles to detour around on an unpaved road. Cascade Bridge engineered its own falsework/girder setting system. After removing the existing bridge deck, Cascade Bridge moved the existing timber truss substructure onto temporary bents adjacent to the original location of the bridge. The new abutments, founded on driven steel H-piles, were place and backfilled. Cascade Bridge then utilized the existing truss to set the 240-foot-long post-tensioned concrete girders. Girders were positioned adjacent to the new structure and swung into place with a tandem crane pick.
Permanent piling consisted of 34 each 16x162 H-piles driven to refusal in bedrock using an ICE-I-46v2 pile hammer. The unique size of the H-piles and tough driving conditions in boulders made this pile driving project one to remember.