Impact of Soil Composition and Electrochemistry on Corrosion of Rock-cut Slope Nets along Railway Lines in China

Taking the slope of Suiyu Railway to study, the research separately studied soil resistivity, soil electrochemistry (corrosion potential, oxidization reduction potential, electric potential gradient and pH), soil anions (total soluble salt, Cl-, SO42- and HCO3-), and soil nutrition (moisture content, organic matter, total nitrogen, alkali-hydrolysable nitrogen, available phosphorus, and available potassium) at different slope levels, and conducted corrosion grade evaluation on artificial soil according to its single index and comprehensive indexes. Compared with other factors, water has the biggest impact on the corrosion of slope protection net, followed by anion content. Total soluble salt has the moderate impact on the corrosion of slope protection net, and stray current has the moderate impact on the corrosion of mid-slope protection net. Comprehensive evaluation on the corrosive degree of soil samples indicates that the corrosion of upper slope is moderate, and the corrosion of mid-slope and lower slope is strong. Organic matter in soil is remarkably relevant to electric potential gradient. Available nitrogen, available potassium and available phosphorus are remarkably relevant to anions. The distribution of soil nutrient is indirectly relevant to slope type.