It may not have been as easy as just adding water, or putting together the assemble-it-yourself furniture from the office-supply store, but precast concrete components let a crew construct a bridge near La Crosse, Wis., almost that quickly.
The bridge, located on Dectrah Coulee Road in La Crosse County, will serve a planned rural subdivision bordering Fox Hollow Golf Course.
To meet Wisconsin Department of Natural Resources requirements to provide an undisturbed natural stream bed and accommodate future runoff, the bridge needed to be 8 feet tall and have 22 feet of clear span over the stream area. It also features wing walls to protect the bridge approaches by helping direct any high-volume flow into the stream bed under the bridge.
Designed to meet the township's road standards, the bridge has a 30-foot-wide top surface and is designed to HS 20 loading standards.
Except for its 4-inch-thick top covering of asphalt, all components for the entire structure were precast by Crest Precast, Inc., in La Crescent, Minn., then trucked to the site, where they were placed by a 220-ton-capacity hydraulic crane from Reynolds Crane Service, Madison, Wis.
The two precast footings, each measuring approximately 5 feet wide and 30 feet long were positioned the week before the rest of the components arrived. A channel running longitudinally in the center of each footing helped align the five precast box sections as they were placed. The design also helped provide a strong connection between the sections and the footings.
Each of the C-shaped box sections that formed the top and sides of the bridge measures 24 feet long, 8 feet high, 6 feet wide, and weighs 46,000 pounds. The crane operator picked each one off a flatbed delivery trailer, then swung it into position at an 80-foot radius before lowering the section onto the footings. All five box sections were placed and aligned in a single day.
The four wing walls were precast complete with footings and also lifted into place by the crane. To complete the project, the top of the structure was surfaced with a 4-inch-thick layer of asphalt.
The bridge is owned by Jim and Barbara Schwier. It was designed by Wiseware LLC, Madison, Wis. Other firms involved in the project included: Coulee Region Land Surveyors, Inc., La Crosse, Wis.; Niebuhr Construction, West Salem, Wis.; and Chosen Valley Testing, Inc., La Crosse.