近距离煤层群上煤层回采的底板应力分布规律

The Floor Stress Distribution Law After Coal Seam Above Exploiting of Contiguous Seams

为了研究近距离煤层群开采时的巷道围岩应力及塑性区发育的变化规律,以某煤矿回采近距离煤层群上位煤层为研究背景,采用理论分析计算、数值模拟的研究方法,对工作面回采期间煤层底板及巷道周边围岩应力的变化规律进行研究,同时模拟研究了回采对原开切眼周边围岩及底板塑性变化情况.计算结果显示:煤层在回采期间底板应力最大值位于回采位置前方10~15 m,随着工作面回采距离的不断增加,其底板的应力集中系数也逐渐变大,同时位于原开切眼处的巷道周边围岩塑性区发育范围也逐渐增大、发育更深.

Taking the mining upper coal seam in close-distance seams of a mine as the research background,this paper uses the theoretical analysis and calculation,numerical simulation to study close distance coal seams group downward mining process of floor stress distribution rules,and to explore the surrounding rock and the bottom of plastic deformation of the original open-off cut.Results show that the peak stress of coal seam floor in the floor is ten meters ahead of the set-up room,and stress concentration coefficient is proportional to working face advancing distance,and at the same time,the roof influenced by original open-off cut becomes wider,and the bottom plastic zone development scope is deeper.