Study on the optimization of reserved size of section coal pillar in shallow buried working face

In order to master the law of pressure variation in shallow buried coal seam and solve the waste of coal resources caused by unreasonable arrangement of coal pillar, taking 308 working face and 306 working face of Yulin Shuangshan Coal Mine as the engineering background, through theoretical calculation, numerical simulation and industrial test, the reasonable reserved size of section coal pillar in 306 working face was studied. The results show that according to the limit equilibrium theory, the width of the elastic core zone inside the coal pillar is 3.8 m, and the limit width of the section coal pillar is 11.4 m. The numerical simulation results agree well with the field measured data. Combined with the actual production geological conditions of the working face, the reasonable reserved size of coal pillar in 306 working face is determined to be 11.5 m, and the corresponding supporting scheme of roadway surrounding rock is proposed. The research results can provide theoretical support and technical guidance for the reserved size of section coal pillar of shallow buried coal seam and effectively improve the rate of coal winning.