高瓦斯煤层冲击地压发生条件与影响因素

发布时间：2018-03-03 02:20

本文选题：冲击地压　切入点：高瓦斯煤层　出处：《力学学报》2017年03期 　论文类型：期刊论文

【摘要】：针对高瓦斯煤层冲击地压问题,用解析方法得到冲击地压发生条件,分析了主要影响因素对满足冲击地压发生条件的临界塑性区半径和临界应力的影响规律.结合五龙矿开采实际情况对影响高瓦斯煤层冲击地压的煤的模量比、煤层瓦斯孔隙压力、支护应力和内摩擦角4个因素做了对比分析.研究发现:高瓦斯煤层在巷道掘进面附近由于存在开挖面空间效应,掘进面前方尚未开挖的煤体对巷道变形起到了限制作用,减少了冲击地压的发生,随着掘进面向前推进,后方一定距离范围内的巷道支护应力增大.随着瓦斯解吸渗流的进行,巷道壁处孔隙压力降低,巷道冲击地压危险性明显提高,此时提高支护应力,冲击危险性有所降低.高瓦斯煤层巷道发生冲击地压的临界塑性区半径和临界应力随模量比、瓦斯孔隙压力的增大而快速减小,随支护应力的增大而增大,临界塑性区半径随内摩擦角的增大而增大,临界应力与内摩擦角不是单调函数关系,存在一个极小值点,当内摩擦角小于此极小值时,临界应力随内摩擦角增大而减小;当内摩擦角大于此极小值时,临界应力随内摩擦角增大而增大.
[Abstract]:In view of the problem of rock burst in high gas coal seam, the conditions of rock burst are obtained by analytical method. The influence of main influencing factors on critical plastic zone radius and critical stress, which satisfy the condition of rock burst occurrence, is analyzed. Combined with the actual mining situation in Wulong Coal Mine, the modulus ratio of coal affected by high gas seam rock burst is analyzed. Four factors, gas pore pressure, support stress and angle of internal friction, are compared and analyzed. It is found that the space effect of excavating surface exists in high gas coal seam near roadway driving surface. The coal body which has not been excavated in front of the excavation has limited the deformation of the roadway, reduced the occurrence of the impact ground pressure, and increased the support stress of the roadway in the range of a certain distance with the advance of the heading surface. As the gas desorption and seepage proceed, the roadway support stress increases with the advance of the driving surface. With the decrease of pore pressure at the wall of roadway, the risk of rock burst is obviously increased, and the support stress is increased and the risk of impact is reduced. The critical plastic zone radius and critical stress ratio of rock burst in roadway of high gas coal seam occur with modulus ratio. The gas pore pressure decreases rapidly with the increase of support stress, and the radius of critical plastic zone increases with the increase of internal friction angle. The critical stress and the angle of internal friction are not monotone function, and there is a minimum point. When the internal friction angle is smaller than this minimum, the critical stress decreases with the increase of the internal friction angle, and when the internal friction angle is greater than this minimum, the critical stress increases with the increase of the internal friction angle.
【作者单位】：辽宁工程技术大学力学与工程学院冲击地压研究院;辽宁大学物理学院;
【基金】：国家重点研发计划(2016YFC0801401) 国家自然科学基金(51174107,51374119) 国家青年自然科学基金(51404131)资助项目
【分类号】：TD324

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