考虑松动圈影响的钻孔瓦斯抽放合理封孔长度确定研究

摘要

In this paper ,through ultrasonic and drilling into the field test and theoretical calculation ,the study is carried out to determine the range of loose ring of coal mining and reasonable length of hole sealing of the gas drainage borehole on No 11071 working face of Wanghangzhuang mine .It is determined that the width of unloading zone of surrounding rock is 8 .87 m at No 2-1 coal seam ,and limit width of equilibrium zone is 9 .87 m with 10 m of reasonable hole sealing depth .The theo-retical calculation result from limit equilibrium method is consistent with test results obtained by methods of ultrasonic wave and borehole monitoring .%以王行庄矿11071工作面为工程试验地点，通过超声波和钻孔窥视现场测试，结合理论计算，开展了瓦斯抽采煤巷松动圈范围和瓦斯抽放钻孔合理封孔长度确定的研究。确定了王行庄11071工作面二1煤层围岩卸压区宽度为8．87m，极限平衡区宽度为9．87m，合理封孔深度为10m；通过极限平衡法理论计算得到的结果与超声波法、钻孔窥视法的测试结果基本相符。