瓦斯抽采巷(孔)的合理布置是实现邻近层卸压瓦斯精准抽采的基本前提。在深入分析覆岩关键层运动对邻近层瓦斯卸压运移控制机制的基础上，提出了基于关键层运动的邻近层卸压瓦斯抽采优化设计新方法。研究结果表明：邻近层卸压瓦斯抽采巷(孔)的合理布置层位为垮落带边界至导气裂隙带最大发育高度之间的空间范围，导气裂隙带最大发育高度可按基于关键层位置的导水裂隙带高度预计方法来确定；邻近层卸压瓦斯抽采巷(孔)的合理层面位置为导气裂隙带内的“O”形圈裂隙区中部，“O”形圈裂隙区宽度可按其与煤层采高、覆岩关键层结构及采深的函数关系式进行预计。该方法在阳泉矿区邻近层卸压瓦斯实践中得到了应用和验证，邻近层卸压瓦斯抽采率稳定在92%，能较好地指导煤层群开采条件下煤与瓦斯共采实践。

The reasonable layout of gas drainage roadway (borehole) is the basic prerequisite to realize precise drainage of pressure-relief gas in adjacent strata. Based on the in-depth analysis of control mechanism of movement of overburden key strata on pressure relief and migration of adjacent strata, a new Optimization designing method of pressure-relief gas drainage in adjacent layers based on key strata movement was proposed. The results show that the reasonable layout of pressure-relief gas drainage roadway (borehole) in adjacent strata is the spatial range between the boundary of collapse zone and gas-conducting fracture zone, and the maximum development height of the gas-conducting fracture zone boundary from coal bed roof can be determined by the method to predict height of fractured water-conducting zone by location of key strata. The reasonable layer position of the adjacent pressure-relief gas drainage roadway (borehole) is the middle of “O” shaped fissure zone. The width of “O” shaped fissure zone can be predicted according to the functional relationship with the mining height, the overlying key stratum structure, and the mining depth. This method has been applied and verified in practice of adjacent pressure-relief gas in adjacent layers in Yangquan mining area,and its adjacent layer pressure-relief gas drainage rate can reach to 92%, which can better guide the practice of coal and gas co-mining under the coal seam group mining conditions.

0 引言

1 覆岩关键层运动对邻近层瓦斯卸压运移的控制机制

2 基于关键层运动的邻近层卸压瓦斯抽采优化设计方法

   2.1 卸压瓦斯抽采巷(孔)的布置层位

   2.2 卸压瓦斯抽采巷(孔)的层面位置

   2.3 卸压瓦斯抽采优化设计流程

3 工程应用

   3.1 卸压瓦斯运移“三带”高度预计

   3.2 导气裂隙带内“O”形圈裂隙区宽度预计

   3.3 邻近层卸压瓦斯抽采优化设计

   3.4 实施效果

4 结论