Accelerated testing of plain and epoxy-coated reinforcement in simulated seawater and chloride solutions

To simulate marine and bridge deck environments, plain and epoxy-coated reinforcing steel bars were cast in concrete slabs and exposed in the laboratory to synthetic seawater and 3% sodium chloride solution. They were monitored on a regular basis using the linear polarization and open-circuit potential techniques. The concrete slabs had a water to cement ratio of 0.60 and the steel reinforcement had 20 mm concrete cover. The epoxy-coated bars were with no damage, and 1% and 2% damage to the coating. A 2-year monitoring program indicated that the corrosion current density was negligible for epoxy-coated bars with no damage to the coating regardless of the exposure conditions and that undamaged epoxy-coated bars provided excellent performance in preventing corrosion activity in reinforced concrete structures subjected to a chloride environment. Similarly, rebar with damaged epoxy coating gave no evidence that sufficient rust had accumulated at the steel/concrete interface to cause the concrete cover to crack. (C) 2001 Elsevier Science Ltd. All rights reserved.