Technology of water hazard control with protection layer for gassy coal seam

The coal seam 3 in Zhaozhuang mine of Jin Coal Group is a highly gassy seam, gas drainage is difficult, there exist hidden unsafe hazard of coal and gas outburst, also the problem of mining under water pressure, restricting seriously the safe and highly efficient production in the mine. Putting forward a scheme of mining with protection layer, the paper proposed to mine the thin seam 8^-1 firstly, to release the stress of coal seam 3, to increase the gas permeability of coal seam, to formulate the strategy of water control for seam 8^-1 in case of mining under water pressure. Ultimately the safe gas drainage in seam 3 was realized, the work of water hazard control went well. This case has certain guiding significance for engineering practice in the similar coal mines with high gas and mining above confined water.