The effects of anode distance and corrosion activity on current distribution for ICCP systems

Abstract

One of the most effective techniques to mitigate corrosion of steel reinforcement in concrete is impressed current cathodic protection (ICCP). This technique has been widely used for several decades; however, there is limited research systematically studying the various factors affecting the distribution of cathodic current over the area of steel reinforcement. Understanding how current is distributed in an ICCP system is crucial for its design to ensure that all areas of steel are sufficiently protected, and overprotection of certain areas is avoided. In this study, the effect of distance of the anode from the steel and level of corrosion on current distribution is investigated by applying a potential sweep and measuring the steel potential and current for specimens with three layers of steel at different depths. The findings from this study revealed an inverse relationship between cathodic polarisation with steel distance from the anode and that higher levels of corrosion can cause a more non-uniform current distribution favouring the closest bar to the anode.