Reinforcement and cathodic protection on corroding concrete elements using carbon fibers based composites

Abstract

 Abstract A Carbon fiber reinforced polymer (CFRP) composite was used as external reinforcement and as a cathodic protection (CP) system of steel in concrete elements. Electrical conductivity was tested for different epoxy resins by varying the amount and length of the carbon fibers used. Three of them were chosen for the testing program in concrete elements. The CFRP composites were glued to the concrete specimens using such selected conductive resins, then electrically connected with one of the rebars and used as impressed current anodes. A direct electrical current was applied between the CFRP composite (anode) and the rebar (cathode) at different current density magnitudes (50, 100, and 1000 mA/m2) during 200 days. The results obtained so far have demonstrated that the CFRP external reinforcement used in this investigation can also work as an anode in a cathodic protection system (CP). No mechanical adverse effect was found on the composite and the epoxy resin selected, although the current densities applied were greater than those used in real structures.