A zinc/hydrogel system has been developed for reinforced concrete. This system consists of a thin foil the cathodic protection of steel in
of zinc which is attached to the concrete surface by an ionically conductive hydrogel adhesive. A direct electrical connection between the zinc and the reinforcing steel allows the zinc to iimction galvanically, polarizing the steel and protecting it from corrosion, Zinc, aluminum, and several aluminum alloys were tested as anodes in contact with hydrogel adhesives, and zinc was found to oiier the best combination of working potential, resistance to passivation, cost and availability. Several hydrogels used for medical applications were found to be inadequate for this use, but a hydrogel adhesive was developed specifically to bond sacrificial anodes to concrete. This hydrogel achieved a total charge in accelerated testing equal to 12 years of life at current densities normally used for cathodic protection. Zinc/hydrogel was installed on about...
Keywords: cathodic protection, concrete, corrosion, reinforcing steel, zinc, hydrogel.