Abstract Manager

The Fifth Street Bridge located in Courtenay, British Columbia was constructed in the 1960s and consists of a steel truss frame and reinforced deck supported by steel girders and two abutments.  The deck reinforcement was corroding due to exposure to deicing salts.  However, it could not be easily replaced as the top flanges of the supporting steel girders were embedded in the bottom half of the bridge deck.   As part of the rehabilitation, the City of Courtenay, the bridge owner, requested the design and installation of an impressed current cathodic protection (ICCP) system to protect the reinforcement in the deck.  Due to the presence of embedded beam flanges, the contractor was concerned about the risk of shorting the ICCP system to the embedded beam flanges, which would make the ICCP system inoperable.   To address these concerns, a combination of impressed current and galvanic systems was used on this project.  The ICCP system was designed and installed in the top of the deck to protect the rebar and a targeted galvanic system consisting of discrete anodes was installed in the deck underside to protect the top flanges of the supporting steel girders embedded in the deck.  A targeted approach was used for protecting the beam flanges where discrete anodes were only installed in areas of active corrosion resulting in cost saving to the owner compared to a global approach. The combined galvanic and ICCP system was monitored remotely for 6 months after its activation to ensure its continued optimal performance.