Stainless steel in chloride-contaminated concrete after carbonation

To minimize the consumption of natural resources for the concrete production, a possible solution is the use of chloride-contaminated raw materials. However, their use is forbidden for reinforced concrete structures, since they can promote the corrosion of carbon steel reinforcement. Within the SeaCon project “Sustainable concrete using seawater, salt-contaminated aggregates, and non-corrosive reinforcement”, financed by the Infravation program, the utilization of chloride-contaminated raw materials for the production of a sustainable concrete, when combined with stainless steel rebars, is studied. Preliminary results showed that different stainless steel types (austenitic and duplex) are suitable to be used in concretes made with chloride-contaminated raw materials and exposed outodoor (unsheltered) in the absence of further chlorides penetration. However, in time, carbonation can reach the bars and the corrosion behaviour of stainless steel might change. This paper focuses on the evaluation of the corrosion behaviour of stainless steel reinforcementin carbonated concrete.