ESTIMATING THE SERVICE LIFE OF EPOXY-COATED REINFORCING STEEL

Corrosion protection performance of fusion bonded epoxy-coated reinfor cing Steel (FBECR) was evaluated in chloride doped simulated concrete pore I,ater solutions and field structures. Results demonstrate that a different corrosion protection failure mode exists in the field than in short-term laboratory studies. In laboratory studies, the chloride is at the bar surface area immediately and the degree or corrosion pro tection is a function of the quality of the coating. In field structur es, the epoxy coating debonds from the steel in moist-wet concrete. Th e rare of epoxy debondment and the chloride increase at the bar depth determine if the chloride corrosion threshold limit is reached before or after the epoxy debonds. If the coating is debonded when the chlori des reach the corrosion threshold limit, corrosion takes place under t he coating in an acidic environment and the corrosion protection of FB ECR is nil. In Virginia, FBECR may provide protection for about five p ercent of the bridge decks and thus FBECR is not a cost - effective co rrosion protection system for Virginia bridges.