Time-dependent performance of concrete surface coatings in tidal zone of marine environment

Corrosion induced by salinity of marine environment is a great threat for significant infrastructures which are placed in such areas. Concrete surface coating is one of the main materials which are used in new or repaired concrete structures which are located in corrosive environment. In this study six different concrete surface coatings are implemented on the surface of concrete and the performance of these coatings has been investigated during 5 years of exposure in tidal zone of Persian Gulf region. According to obtained results, epoxy polyurethane and aliphatic acrylic are proven to be the most efficient coatings, which cause a reduction the chloride penetration and enhance the service life of concrete structures. However, performance of surface coatings is time-dependent and coated concretes must be recoated with distinct surface coating in proper time which means before coatings deterioration time. A new method for evaluating the performance of surface coating has also been proposed.