The NC Department of Trans-portation awarded Tidewater Skanska, Inc. a $15M contract to replace the old low-level swing span bridge over the In-tracoastal Waterway near Fair-field, NC with a new high-level, fixed span bridge. The new bridge will have a minimum clearance of 65 feet between the bottom of the steel girders and the waterway below. The Fair-field Bridge, part of Highway 94, is in the sparsely populated central coastal plain of North Carolina and is the only direct corridor between the towns of Fairfield and Columbia.
The substructure of the new bridge was completed and then the installation of the girders and decks began. The most challenging part of this project was erecting the steel plate girder sections that make up the three largest spans of the bridge. In all there are 27 girder sections with the largest sections weighing 69 tons each.
Because the surrounding marshland limited accessibility and the narrow waterway would not accommodate some of Tidewater's larger cranes, an elaborate lifting plan was de-signed by Tidewater's Engi-neering Department. The plan called for using two and some-times three cranes (2 were land-based and 1 was on a barge) to place a single girder section. All together the erection plan required 12 multi-crane lifts. The order of each lift was also critical since the girders, if se-quenced incorrectly, would po-tentially not support their own weight and could fail. The lift-ing plan identified the need to erect the large 69-ton plate girder sections first, "balanc-ing" them on bents until they could be correctly spliced with the adjacent sections of steel plate girders.
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