July 4, 2017
Cathodic protection was the preferred solution when corrosion was discovered in a pedestrian bridge and a podium slab at the State University of New York, Plattsburgh.
Rehabilitation work was carried out in two phases and required meticulous preparation to ensure successful installation. Using GPR, CCL identified the location of existing reinforcement within the structural members before holes were then drilled to accept the anodes. Precise location of the cavities was essential to avoid the existing rebar and maintain the integrity of the structure. A total of 500 holes were drilled for Phase 1, and 3,100 holes were drilled for Phase 2. The connecting wires installed in channels between the holes required 300 m (1,000 ft) of concrete to be chased out for Phase 1 of the project and 1800 m (6,000 ft) for Phase 2.
As each zone was connected, rigorous testing was carried out to ensure correct functionality before encapsulation. Testing completed, the holes were filled with special grout. A titanium mesh was then placed over the system and a concrete topping slab 15 cm (6”) in depth was cast.
After energising the system CCL will continue to check the installation on a monthly basis, while at the same time training in-house maintenance personnel at the university to monitor the system correctly. After one year of monitoring the system will be handed over to SUNY.