Assessment of interference scope induced by stray current in the metro depot for the corrosion risk of buried metal pipeline

The hazard of stray current attracts more and more attention due to the potential infrastructure failure caused by the electrochemical corrosion. In view of the poor insulation performance and lack of stray current collection system in the metro depot, stray current leakage becomes particularly evident in this area. In order to evaluate the corrosion risk of buried metal pipeline surrounding metro depot, an assessment model for interference scope induced by stray current is proposed in this paper. The distribution of stray current is calculated based on the resistive network by considering different boundary conditions in different areas of metro depot, and the interference scope is assessed by surface potential gradient for corrosion risk of corroded pipeline. Moreover, the characteristics of surface potential gradient distribution in different areas of metro depot and the influence of electrical parameters are analyzed. Finally, the proposed model is verified through simulation and experimental results.