Rehabilitation of a Historical Bridge Exhibiting Severe Corrosion Damage in Florida

The “Bridge of Lions” is a National Historic Landmark located in St. Augustine, Florida (the oldest continuously occupied European city in the U.S.). The bridge was built in the 1920's and uses a combination of structural steel and steel reinforced concrete to provide an arch type substructure with a Mediterranean look deck.  During its near 90 years of service, the aggressive marine environment at the location has prompted severe corrosion induced damage throughout all its components.

In 2004, the Florida Department of Transportation awarded a contract to rehabilitate the bridge. The contract included among others: replacement of some bridge elements, impressed current cathodic protection on selected reinforced concrete elements that could not be replaced, and thermally applied zinc on steel girders and structural steel attachments.  It is anticipated that the restoration work will be completed in 2010, but the corrosion control methods will be functional upon installation to avoid the onset of corrosion during the construction period.

This paper discusses the design and installation of the corrosion control measures as well as their initial performance.