Repair and cathodic protection of suburban concrete bridges

An increasing number of suburban concrete bridges are affected by chloride-induced corrosion of their reinforcing steel. Traditional patch repair of the damaged areas of concrete is recognised to be a short-term solution because it does not prevent further damage. Cathodic protection is now widely used to extend the life of such structures by arresting the corrosion in all areas that are at risk, in conjunction with repairing whatever has already been damaged. This paper reviews two similar bridges in the Illawarra, and demonstrates how different environmental and structural conditions affect the design and construction methods required for the repair and protection of each.