Fox River Bridge Receives Engineering Excellence Award

Gantry System.jpgTwo unusual design and construction methods were used to remove the aging six-lane twin bridge and build a new eight-lane twin bridge in the same location, while simultaneously keeping six lanes of traffic open. The substructure of the new bridge – footings and piers – was constructed underneath the existing bridge while it remained in service.

This unusual bridge-under-bridge design was possible because the beams used in the new bridge deck are much longer and deeper than the previous beams. During construction of the new bridge, a gantry system was used instead of a large crane to place the massive 2,000-pound deck beams. The gantry system alleviated the need to position a large crane close to the rare forested fen located adjacent to the bridge.

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