A crew in Coeur d’Alene, Idaho, leveraged creation of a sliding girder installer to complete repairs to the 56-year-old I-90 Pennsylvania Avenue Bridge in just three weeks this spring, saving about $161,000 and shaving three months off the closure.
The work was recognized with a department Excellence in Transportation award Nov. 17 in the Maintenance & Operations category, and the sliding girder innovation was also named one of the Idaho Transportation Department’s (ITD) Best of the Best for 2016 innovations in the Economic Opportunity category in late October.
The repairs extended the life of the bridge to safely serve area drivers (approximately 22,000 each day) until the bridge can be fully replaced. Reducing the duration of the closure allowed general traffic to resume using the bridge much sooner, and also benefited local law enforcement and emergency responders, who use the bridge as a critical conduit into the homes and businesses of that neighborhood.
ITD’s crew completed these repairs at a cost of $39,000 (most of which was steel) compared to the estimated $200,000 it would likely have cost a contractor to do the same work. The repairs also addressed needs of heavy truck traffic, nearby residents and school children.
The project involved shoring up the girders on the westbound approaches to the bridge. The approach had dropped approximately 3/8 in., creating an unsafe driving surface.
By devising the girder installer/girder support system, the crew could lift the six girders, each weighing about 300 lb, into place three at a time rather than one at a time, as a regular contractor would likely have done.