Monitoring of the Long-term Performance of Stainless Steel Reinforcement in Saline Environments

Abstract

The aim of the present work is to evaluate the corrosion behaviour of different types of stainless steel reinforcement and to determine their suitability for the use in a chloride contaminated concrete environment. Electrochemical impedance spectroscopy (EIS) measurements were performed on steel reinforcement specimens in a simulated concrete pore solution containing chlorides. The concrete specimens, with embedded electrical resistance (ER) probes for corrosion monitoring, were subjected to cyclic wetting-drying. Reinforced concrete columns with ER probes and coupled multi-electrodes for the measurement of partial currents were exposed to a real marine environment. Traditional stainless steel reinforcement in chloride contaminated environment behaves significantly better than carbon steel. Austenitic low-Ni stainless steel showed similar corrosion resistance to that of the traditional stainless steels, whereas ferritic stainless steel was found to be unsuitable for use in such environments. ER probes and coupled multi-electrodes were shown to be promising methods for corrosion monitoring in concrete.