Innovative engineering restored life to a landmark in the “Nation's Oldest City,” St. Augustine, Fla. The $89-million restoration of the historic 1920s-era Bridge of Lions brought the structure up to modern engineering standards. The 1,545-ft-long bascule structure connects the city's downtown with Anastasia Island and the beaches.
The project team preserved the arched approach span's girders and bascule piers and tower. Before dismantling the old bridge, the contractors first built a temporary bridge to carry traffic during construction.
Skanska removed the steel girders, which a fabricator then inventoried, evaluated and rehabilitated—typically only replacing cover plates and flange angles—before returning them to their original positions.
Reynolds, Smith & Hills created a new hidden interior steel framework, with a longitudinal stringer system parallel to the main girders that shifts most of the load to the approach piers from the girders.
It also engineered an innovative foundation system for the original bascule piers that added four new drilled shafts around the perimeter and one through the center of each pier. This foundation system, also hidden from view, extends roughly 75 ft deeper than the original foundations and meets contemporary criteria for ship impact and scour.
Owner: Florida Dept. of Transportation, Lake City, Fla.
Contractor: Skanska USA Civil, Virginia Beach, Va.
Construction Manager: URS Corp., West Palm Beach, Fla.
Engineer: Reynolds, Smith & HIlls, St. Augustine, Fla.
Reynolds, Smith & Hills