关键词: 低渗透性, 煤层群, 采动裂隙垂向分带, 卸压瓦斯抽采, 地面钻井部署

Abstract: Based on depositing conditions of high gas and low permeability of coal seam group in Huainan mining area, this article analyzes the movement and failure characteristics of overlying strata, the movement and deformation characteristics of relief seam, the vertical zoning characteristics of mining fractures and stress zoning characteristics of relief seam through the analogue test. Conclusion is drawn that there are annular fracture area, vertical fracture area, and the remote relief seam fracture area from the roof of goaf in the first mining layer. According to the developing characteristics of the mining fracture areas, this article puts forward the deployment method of surface drilling in the drainage of pressure relief gas. The “ ”-type , “│”-type and “L”-type ground drilling are respectively put outside the starting cutting hole 1117(1) work face, inside the wind tunnel, and in front of the work face in Guqiao Coalmine. The relationship among the ground drilling locations, drilling type, drilling stability and relief gas drainage effect is probed into and found.

Key words: low permeability, coal seam group, vertical zoning characteristics of mining fractures, relief gas drainage, ground drilling locations