Concrete Coatings for Mitigation of Embedded Rebar Corrosion

Chloride-induced corrosion is the prime reason for degradation of embedded rebar in marine structures. The present study experimentally investigates the effectiveness of two-component epoxy (EPX) and single-component moisture-cure (MC) polyurethane concrete coatings in reducing the rate of chloride ingress and thus mitigating rebar corrosion. The non-steady-state migration coefficients of the concrete cured for 28 days and coated with MC and EPX coatings were 22% and 11%, respectively, of that of the concrete with supplementary cementitious material cured for 84 days. MC coatings mitigated the corrosion rate of embedded rebar by 7.6 times compared to uncoated specimens, whereas EPX coatings mitigated the rate by 23 times.