Corrosion behavior of epoxy/zinc duplex coated rebar embedded in concrete in ocean environment

The corrosion behavior of epoxy/zinc duplex coated rebar embedded in concrete is evaluated comparing with the black steel, galvanized and epoxy coated rebars for a long term in ocean environment. The effect of mechanical damages of epoxy coatings on the corrosion protection is examined. The epoxy coated and epoxy/zinc duplex coated rebars show the higher anti-corrosion performance than other types of rebars. However, once the epoxy coating is mechanically damaged, the more serious corrosion may occur in the damaged area of epoxy coated rebar in concrete. The epoxy/zinc duplex coating remains a good corrosion protection to steel in concrete even when suffering from some mechanical damages.

► The corrosion of epoxy/zinc duplex coated rebar is examined in the sea environment.
► The effect of coating damages on corrosion behavior is also studied.
► The epoxy coating has good protection to steel, but largely effected by the damages.
► The duplex coating remains good protection and is less effected by the damages.