Zhenchengdi Mine, Shanxi Xishan Coal Electricity Co., Ltd.

动压作用影响下镇城底煤矿巷道变形严重,增加了巷道维护的难度。为提高巷道围岩稳定性,对直接顶板和矸石的压缩载荷以及顶板悬臂梁长度的影响规律进行了研究,建立了动压作用下采空区巷道覆盖层结构模型和煤柱应力模型,分析了直接顶板厚度、硬度和变形对采空区稳定性的影响,提出了动压作用下采空区“槽梁”结构和煤柱稳定性的理论判据,基于镇城底矿22305综采工作面的地质条件,从切顶卸压、煤柱设计、围岩加固等方面采取优化措施。结果表明,采用注浆锚索梁对顶板进行加固,实施双向注浆锚索对窄煤柱进行加固,使煤柱宽度由15m减小到4m;巷道顶板和两帮变形分别为268mm和105mm,煤柱应力集中系数为1.20,有效实现了采空区巷道覆盖层及煤柱稳定性控制。

Under the influence of dynamic pressure action, the deformation of the roadway in Zhenchengdi Coal Mine is severe, which increases the difficulty of roadway maintenance. In order to improve the stability of the roadway surrounding rock, the influence laws of the compression load of the direct roof and gangue, as well as the length of the roof cantilever beam, are studied. Goaf roadway covering layer structural model and coal pillar stress model under dynamic pressure action are established. The influence of the thickness, hardness, and deformation of the direct roof on the stability of the goaf is analyzed, and theoretical criterion for the stability of the "groove beam" structure and coal pillar under dynamic pressure action are proposed. Based on the geological conditions of the 22305 fully mechanized mining face in Zhenchengdi Mine, optimization measures are taken from the aspects of roof cutting and pressure relief, coal pillar design, surrounding rock reinforcement and so on. The results show that the width of the coal pillars is reduced from 15 m to 4 m by using grouting anchor cable beams to reinforce the roof and implementing bidirectional grouting anchor cables to reinforce narrow coal pillars; The deformation of the roadway roof and two sides is 268 mm and 105 mm, respectively, and the stress concentration coefficient of the coal pillar is 1.20, effectively achieving stability control of the goaf roadway covering layer and coal pillar.