BNSF Railroad Columbia River Swing Bridge Span Repair
Start Date: 2014
End Date: Fall 2014
Hamilton was presented with a unique challenge when selected by the BNSF to repair and reinforce the U1 connections of its Columbia River Swing Span Bridge. Over the life of the bridge the continual cycles of opening and closing the swing span had resulted in wear of the U1 pin connection, which in turn caused the ends of the span to sag and prevented the lock from operating correctly.
The greatest challenge to the project was access. Hamilton initially planned to conduct the repair with limited short term duration closures. However, given the extreme volume of rail traffic that approach turned out to be too disruptive to the BNSF schedules. Further compounding the challenge was the volume of river traffic which required the bridge to be operable. Consequently, Hamilton offered the alternative of using a top down approach that would allow the bridge to remain in service. Hamilton installed scaffolding, fabricated and erected a mobile crane that was attached to the top of the structure. This eliminated the need to occupy the tracks and therefore allowed the tracks to stay in service during the duration of the repair.
Hamilton's interactive approach and close working relationship with the client resulted in an alternative delivery method that minimized impact and exceeded expectations.