Study On The Evolution Law And Application Of Three Fields Roadside Of Deep Coal Roadway In Shoushan Coal Mine

Mining deep coal seam is greatly affected by in-situ stress,which can easily lead to roof disasters,rock burst and other accidents,seriously restricting the safe and efficient production of coal mine.Influenced by mining activities,the working face and roadside coal and rock mass are under mining stress.At present,the distribution and evolution of stress field,fissure field and gas field near roadway are not clear,which seriously restricts the development of roadway support and gas extraction.Based on this background,aiming at the field demand of Shoushan No.1 Coal Mine,the distribution and evolution of "three fields" near deep coal roadways are studied by means of theoretical analysis,numerical simulation and field measurement.The main work and achievements are as follows:(1)The stress distribution and evolution law of coal body were tested in front of the heading of 12100 machine roadway in Shoushan Coal Mine and beside the middle roadway of 12090 mining face.Influenced by roadway excavation,the stress value along the direction of 12100 machine roadway is increasing rapidly at about 10-15 m away from the roadway face,and the stress concentration coefficient is about 1.27-1.39.The stress concentration zone along the roadway along the inclination direction of coal body is about 5-10 m.Under the influence of mining,the stress value at about 26-39 m away from the mining face in front of 12090 mining face shows a rapid growth trend.The stress concentration coefficient ranges from 1.76-1.92,and the stress concentration zone near the roadway is about 6-14 m along the inclination direction of coal body in 12090 middle roadway.With the continuous advancement of the mining face,the "three zones" around the roadway are constantly changing,the pressure relief zone is increasing,the stress concentration zone is increasing and gradually transferring to the deep coal body.(2)Fissure field distribution and evolution law and gas field distribution law were tested in 12090 stope of Shoushan Coal Mine.The crack field near roadway in 12090 mining face was detected by network parallel electrical method.The results show that the closer the coal body near the roadway is to the cutting hole of the mining face,the greater the stress and crack development and expansion degree of the coal body,the wider the area of pressure relief zone and stress concentration zone near the roadway gradually,and the depth of the coal body constantly turns.The test results of gas parameters of coal body near roadway show that the gas content increases gradually with the increase of coal body inclination depth in the range of 0-21 m along the coal body inclination in the ventilation roadway of 12090 mining face.(3)According to the actual coal seam geology and mining conditions of Shoushan Coal Mine,the dynamic evolution model of gas-solid coupling mining stress is established by using FLAC 3D simulation software.The distribution and evolution law of stress field,stress field and gas field in heading face and mining face are simulated.The simulation results show that: The stress increases rapidly along the roadway direction about 12-14 m away from the roadway face,and the stress concentration coefficient ranges from 1.30-1.38.The stress concentration zone near roadway is in the range of 4.7-11.5m along the inclination direction of coal body.Vertical stress value increases rapidly at the distance of 23-42 m from the mining face in front of the mining face,and reaches the peak stress value at the distance of 11-14 m from the mining face in front of the mining face.The stress concentration coefficient ranges from 1.74-1.91.The mining face along the inclined direction is about 6-14.3m in the stress concentration zone near the roadway.The law of gas distribution shows that the gas pressure increases gradually with the increase of coal body tendency depth in the range of 0-21 m along the coal body tendency in the ventilation roadway of mining face.The research results reveal the distribution and evolution law of stress field,fissure field and gas field beside roadway,which provides a basis for reasonable determination of roadway support,gas drainage and sealing parameters in Shoushan Coal Mine.It is of great significance for improving the support of mining face and roadway,gas drainage effect and ensuring safe and efficient mining.