Client
Wisconsin Department of Transportation District 3
Services provided
Condition surveys
Construction monitoring
Materials engineering
Pavement engineering/analysis
Structural evaluation
Project overview
The two-lane, 305-foot-long, Leig Avenue Bridge over the Wolf River in Shawano, Wis., was constructed in 1954. In 2003, the Wisconsin Department of Transportation (WisDOT) scoped this structure for a deck replacement due to surface deterioration. STS offered a unique rehabilitation alternative to Shawano County and WisDOT during the bidding process – hydrodemolition.
Hydrodemolition is a concrete removal method that uses high-pressure water jets to remove unsound concrete down to a sound, non-uniform bonding surface. It does not cause the microscopic cracks in substrate concrete that are often noted with mechanical means and is capable of easily removing concrete without damaging surrounding reinforcing steel.
Approach
The only significantly deteriorated portion of the superstructure was the wearing surface of the deck. Therefore, STS proposed simply rehabilitating the existing deck riding surface using hydrodemolition to minimize the amount of debris that fell into the scenic Wolf River.
At the preconstruction meeting, the contractor laid out their plan of collecting the clear water from the hydrodemolition in two inlets and pumping it into a tanker for land spreading at an approved waste site.
The project also included new car/pedestrian bridge rails and guard rails, and the addition of a new traffic separation railing between the traffic lane and the sidewalk. STS cleaned the steel beams of the structure with a proprietary media blasting additive to encapsulate lead contaminants and allow the waste to be disposed of as a non-hazardous material. Lastly, the bridge was painted.
Client benefits
- STS provided an alternative con-struction technique to increase the structure’s lifespan from 10 years to 20 to 30 years.
- STS provided environmentally friendly construction alternatives.
- WisDOT received the structure safety upgrades they desired.
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