Numerical study on matrix deterioration at the anodic region of impressed current cathodic protection system

Impressed current cathodic protection (ICCP) is one of the typical methods to protect reinforced concrete from corrosion damage. However, continuous application of current will induce acidification near the anodic region and cause degradation of ICCP system. In this study, the chemical characteristics of cement-based matrix at anodic region under the effect of ICCP are evaluated by an integrated numerical platform. Validation is first conducted based on the available experimental data, then parametric study is done to investigate the key factors influencing matrix deterioration. Finally, possible countermeasures to mitigate anodic deterioration are raised. From this study, it is found that the pH value of pore solution at anodic region gradually decreases as the current applies, resulting in the decline of matrix conductivity as well as the protection efficiency, which becomes the main reason for the ICCP degradation.