Study on evolution law of overburden structure based on microseismic distribution characteristics

There are several key layers with large thickness above the 402 working face of wide coal pillar in Hongqinghe Coal Mine. The existence of key layers will significantly increase the peak value of abutment pressure and its influence range. Based on the microseismic distribution characteristics of 402 working face are analyzed based on microseismic monitoring data. It is found that the microseismic distribution of working face during mining is mainly affected by advanced abutment pressure, lateral abutment pressure of goaf, tectonic stress and stress concentration caused by mining technology factors. The influence range of lateral abutment pressure of working face is about 180 m, and the stability of roof structure in 120 m area of goaf is poor, which is easy to induce large energy mine earthquake. The influence range of the advance abutment pressure of the working face is about 240 m. The coal and rock masses in front of the working face are easier to reach the limit state under the superposition of the latera