In mining closely spaced coal seams, the roadway arrangement for gas drainage in lower coal seams is always a concern. This paper uses mechanical model calculations and numerical simulation postprocessing methods to study the stress deviator distribution characteristics of the surrounding rock in the gob under various conditions. By calculating the distribution of the stress deviator, a reasonable location for the gas drainage roadway in engineering construction is determined, and the rationality of the roadway location selection is verified by the changes in the stress deviator in the surrounding rock during the mining of the lower coal seam. The research includes the following main results. (1) The theoretical formulas for vertical, horizontal, shear and stress deviator under a single gob of an inclined coal seam are derived through the semi-infinite body solution, and the stress deviator distributions in the roof and floor of the coal seam below the gob are calculated. The main factors affecting the distribution of stress deviator are determined by the following parameters: coal seam depth H, horizontal lateral pressure coefficient λ and coal seam inclination θ. (2) Through FLAC3D model calculation and postprocessing, the stress deviator distributions under different conditions are obtained, and the influences of various factors on the stress deviator distribution below a gob are analyzed. (3) Using the calculated theoretical results for the stress deviator and the distribution of the stress deviator obtained by the numerical method, the position of the gas drainage roadway during the mining of the upper coal seam is preliminarily selected; using numerical simulation of mining the lower coal seam, the stress deviator distributions in the surrounding rock during the mining of the lower coal are obtained, thus verifying the scientific basis and rationality of the gas drainage roadway layout.

在密集煤层开采中，下煤层瓦斯抽采的巷道布置一直是人们关注的问题。本文采用力学模型计算和数值模拟后处理方法，研究了不同条件下采空区围岩应力偏差分布特征。通过计算应力偏子的分布，确定工程建设中瓦斯抽采巷道的合理位置，并通过下层开采过程中围岩应力偏子的变化验证巷道选址的合理性。煤层。研究包括以下主要结果。(1) 垂直、水平、通过半无限体解推导出倾斜煤层单个采空区下的剪力和应力偏差，计算了采空区下方煤层顶底板的应力偏差分布。影响应力偏差分布的主要因素由以下参数决定： 煤层深度H , 水平侧压系数λ和煤层倾角θ. (2)通过FLAC3D模型计算和后处理，得到不同条件下的应力偏差分布，分析了各种因素对采空区下方应力偏差分布的影响。(3)利用计算得到的应力偏差的理论结果和数值方法得到的应力偏差的分布，初步选定上煤层开采过程中瓦斯抽采巷道的位置；通过下煤层开采数值模拟，得到了下煤层开采过程中围岩应力偏差分布，从而验证了瓦斯抽采巷道布置的科学依据和合理性。