远程覆岩卸压变形及其渗透性研究

运用数值模拟和现场试验相结合的方法，对下保护层开采所引起远程覆岩的卸压变形及其渗透性变化进行了分析与研究。结果表明：下保护层开采将使覆岩产生不同程度的卸压，卸压煤（岩）体产生膨胀变形，生成大量的次生裂隙；同时也导致了水平位移的产生，形成了丰富的竖向裂隙，从而使煤（岩）体的渗透性得到极大的提高。因此，在高瓦斯煤层群条件下，利用下保护层开采所引起的“卸压增透增流”效应，同时结合合理有效的瓦斯抽放方法，可以实现煤与瓦斯两种资源的安全高效共采。

Deformation and permeability characteristics caused by pressure-relief of long-distance strata

The deformation and change of permeability characteristics caused by the exploitation of the long-distance under-protecting coal stratum were analyzed and studied by the methods of numerical simulation and colliery on-the-spot test.The results indicated that the pressure of the long-distance protected stratum was relieved as the result of the exploitation of the long-distance under-protecting coal stratum.The pressure-relief coal or rock strata expanded and the vertical and horizontal displacement happened.As a result great numbers of vertical and horizontal crannies were produced and the permeability of the pressure-relief coal or rock strata increased greatly than before.So on conditions of high-gas coal strata the safe and high-efficient exploitation of coal and gas can be realized if we adopt reasonable exploitation order and efficient gas extraction method by the use of the effects of pressure-relief,permeability and fluidity increasing caused by the exploitation of the long-distance under-protecting coal stratum.