Application of electrochemical organic corrosion inhibitor injection to a carbonated reinforced concrete railway viaduct

As a possible means of alleviating carbonation-induced reinforcement corrosion in aging reinforced structures, electrochemical injection of corrosion inhibitors has been proposed. This method involves application of aqueous solutions of organic base corrosion inhibitors onto the concrete surface with controlled current densities passed between anodes placed within the inhibitor solutions and the embedded steel bars acting as cathodes. This present contribution describes a site trial of electrochemical inhibitor injection applied to a 40-year-old carbonated high-speed railway viaduct in Tokyo. The efficiency of inhibitor penetration to the embedded reinforcement and the electrochemical effects brought about by the proposed method are discussed.