影响煤层瓦斯赋存的岩体结构分析

Analysis on Rock Mass Structure Affecting Coal Seam Gas Occurrence

煤层瓦斯含量是决定煤与瓦斯突出的主要因素之一。利用岩体结构分析的方法研究了围岩岩体结构对煤层瓦斯赋存的控制作用。岩体结构可用岩层效应厚度影响系数来表示,应用该参数研究煤层瓦斯赋存比用煤层顶板岩性及含砂率更科学。岩石的渗透率不等于岩层的渗透率,岩层的渗透率也不等于岩体的渗透率,煤层瓦斯的保存与逸散决定于岩体渗透率;煤层瓦斯在构造运动后主要顺稳定的透气层向大气逸散。

The content of coal seam gas was one of the important factors to coal and gas outburst. The control role of surrounding rock mass structure to coal seam gas occurrence was studied by the method of rock mass structure analysis. Rock mass structure can be expressed by strata effect thickness coefficient,it is more scientific than roof rock and sand content in the study of coal seam gas occurrence. The perme- ability of strata was neither equal to permeability of rock, nor equal to the permeability of rock mass. The occurrence and dissipation of the gas is determined by the permeability of rock mass,the coal gas dissipated from the steady seepage stratum after structural movement.