Analysis of coal mine environment corrosion tendency based on fuzzy comprehensive evaluation method

The coal mine environment is easy to cause corrosion damage to the anchorage material in long-term use because its complexity, which threatens the safety of roadway support. To characterize the corrosion characteristics of coal mine environment, the corrosion factors and corrosion tendency of coal mine environment were studied. The environmental characteristics and main corrosion factors of coal mine were analyzed based on field investigation. The multi-parameter coupling evaluation method of coal mine environmental corrosion tendency is designed by analytic hierarchy process-entropy combination weighting and membership degree analysis. The environmental corrosion tendency grade of underground roadway in Gaojiabao Coal Mine was determined by industrial application test. The results indicate that the coal mine environment can be divided into three categories: water environment, atmospheric environment and surrounding rock environment, including 9 main environmental corrosion factors. By index weighting analysis, the weight of water environment was determined as 0.64829562, the weight of atmospheric environment was determined as 0.22967309, and the weight of surrounding rock environment was determined as 0.12203129. Nine influence indexes of main environmental corrosion factors in coal mines were put forward by membership analysis, such as pH influence index, Cl− influence index and \begin{document}${\mathrm{SO}}_4^{2-} $\end{document} influence index. The membership function of each main environmental corrosion factor was constructed. Combined with index weighting and membership analysis, the multi-parameter coupling evaluation method of coal mine environmental corrosion tendency was designed, the environmental corrosion tendency of coal mine is comprehensively judged by environmental detection, index quantification, evaluation index determination and engineering criterion comparison. The environmental corrosion tendency of the north wing return air roadway, the west wing concentrated auxiliary transportation roadway, the west return air roadway, the 3403 transportation roadway and the 3407 transportation roadway in Gaojiabao Coal Mine were determined as grade V, grade III, grade II, grade III and grade IV by applying the multi-parameter coupling evaluation method of coal mine environmental corrosion tendency. Comparing the results of roadway environmental evaluation and industrual corrosion test, it can be seen that the evaluation method can accurately evaluate the corrosion characteristics of coal mines environmental. This study can effectively evaluate the mine environment and provide guidance for the anti-corrosion support of coal mine roadway.