LABORATORY PERFORMANCE OF ZINC ANODES FOR IMPRESSED CURRENT CATHODIC PROTECTION OF REINFORCED-CONCRETE

Cathodic protection (CP) is used increasingly to mitigate steel reinfo rcement corrosion in concrete. The performance of zinc materials as im pressed current anodes was evaluated. The anode materials investigated included rolled zinc sheets, metallized zinc, and 85% Zn-15% Al. The circuit resistance and the adhesion of the anodes was monitored with p olarization time. Overall performance of arc-sprayed zinc was good. Ho wever, its adhesion to the concrete surface slowly decreased as the cu rrent density, or the polarization period, increased. Penny blank shee ts and metallized 85% Zn-15% Al were found unsuitable as impressed cur rent anodes.