BNSF 0052-0081.40 Bridge Replacement
CM/GC [Construction Manager/General Contractor delivery method]
Originally this project was a design-bid-build job. After a detailed evaluation of the project, Hamilton suggested BNSF change the delivery format to CM/GC. The benefit to BNSF would be a significant time savings in change-outs and sequencing. Hamilton helped guide BNSF through the transition to CM/GC. The CM/GC process allowed Hamilton to determine the best structure and construction approach, which was to build the replacement structure off-line.
This project replaced Bridge 81.4, a 663-foot-long double main track over the Cowlitz River. The new structure is 1100-feet-long, 12 spans, with the longest being the 208-foot deck plate girder spans. The project included constructing a 44-foot-high and 42-foot-wide workbridge, 45 feet above OHW, 720 feet across the Cowlitz River from bank to bank simultaneously. A road was pioneered in on the south side of the project and a geofabric wall was constructed 20-feet-tall off of the north bank to achieve bank to bank access.
This project also included drill slips, girder erection falsework pile below OHW, four 9-foot/10-inch diameter shafts approximately 180-feet-deep, sheet pile shoring, permanent piling, and cast-in-place concrete.
Hamilton's efforts resulted in reducing traffic impacts, leaving one track open at all times.
Major Project Elements: