Research and application of low level drainage technology under rock burst conditions in large goaf

The coal seam 4 in the second panel of Tingnan Coal Mine has strong impact tendency, and the syncline structure runs across the second panel. Between theworking faces 204, 205, and 206 of the second panel, there is 30m coal pillar between the working faces. After extraction in the work faces, a large goaf is formed. The distance between the coalface 207 and the large goaf is 30m coal pillar. During the mining of the working face, especially in the overturned axis area, it is threatened by the water in the large goaf. In order to solve the problem of prevention of drainage in working face 207, low discharge technology under under rock burst conditions in large goaf was studied in Tingnan Coal Mine. Across the working surface 207, a low-level discharge lane was constructed at 30m below the coal seam floor. A discharge hole was drilled in the discharge lane into goafs 206 and temporary water silo 207, after the water in the goaf discharges outside after being led up to the discharge lane. Through the research, the water in the large goaf was successfully led to the outer row of the low-level drain roadway, solving the problem of water-proof and drainage when the working face was traversed in the inclined-axis area, and eliminating the threat of water in the large goaf.