Effect of Soil Salt Content on Stray Current Corrosion of Buried Metal

Abstract

In order to study the effect of soil salt content on the corrosion of buried metal by the stray current in urban rail transit, a small experimental platform for the buried metal corrosion is built. The corrosion rate and mass loss of buried carbon steel specimens in soil samples with or without DC stray current are measured and calculated when different content of NaCl is added into the soil samples, respectively. The experimental results show that the corrosion rate and mass loss of the buried metal increase with the increase of soil salt content. DC stray current will aggravate the corrosion of the buried metal. The corrosion degree of buried metal will be seriously aggravated under the coupling action of DC stray current and salt. When there is no DC stray curren, the corrosion degree of buried metal is relatively small, and the influence of soil salt content on the buried metal corrosion is also relatively small. Finally, a multiphysics simulation model corresponding to the experiment is established to verify the experimental results. The simulation results are basically consistent with the experimental results, which proves the accuracy of the experimental results. The research results can provide a theoretical basis for the corrosion protection design of subway stray current.