Support Design of Lower Coal Seam Mining Roadway in Closed Coal Seams

The 6^# seam and 5^# seam are the closed coal seams in a mine in guizhou. The support problem of lower coal seam is the most important factor for the work. For the problem of support control of lower roadway in this mine, we use filed survey and borehole camera to detect the whole section of rock structure, and analyzed the reason of coal seam failure. Combined FLAC^3D, we studied the bottom stress characteristics in higher coal pillar, and analyzed influence of upper coal seam pillar on the stability of lower coal seam surrounding rock. Then according to the characteristics of stress and deformation of the lower coal seam, we proposed the asymmetric support scheme and achieved good support effect.