采动应力作用煤巷泥质复合顶板稳定性分析

 为研究采动应力作用软岩煤巷泥质复合顶板稳定态势,以高家梁矿20307工作面皮带煤巷为例,通过岩体微观结构特性分析和钻孔窥视仪对煤巷松动圈探测,确定泥质顶板煤巷为应力扩容膨胀型复合地质软岩,变形破坏力学机制为复合型Ⅰ_ABⅡ_BDⅢ_DA机制,提出锚网索带注的耦合支护对策机制,利用FLAC^3D对采用耦合支护对策后泥质复合顶板稳定性进行数值分析,采用现场监测煤巷变形的方法并将两者结果作对比分析。结果表明,软岩煤巷泥质复合顶板稳定性得到有效控制,验证了应力扩容膨胀复合型破坏机理的正确性和耦合支护对策的有效性,为相似地质条件软岩煤巷支护提供参考。

Stability Analysis of Mud Compound Roof in Coal Roadway Under Mining Pressure

In order to study the stability of complex mud roof of coal roadway under the mining pressure, example of the working surface 20307 in Gao Jialiang Coal Mine is presented. Based on the analysis of rocks microstructure characteristics and measurement of surrounding rock loose circle by hole examining method, the complex mud roof of coal roadway is the geological soft rock which is a complex type of stress dilatancy expansion. The mechanisms of roadway damage are complex deformation mechanisms includingⅠ_ABⅡ_BDⅢ_DA, and the bolt-mesh-cable-grout with steel band coupling support design is proposed, which adopts the finite difference program FLAC^3D to simulate the stability of complex mud roof of coal roadway with coupling support; Then it also adopts the in-situ investigation to perform field monitoring for the deformation of coal roadway, and the comparative analysis between numerical analysis and field monitoring is studied. The results reveal that stability of complex mud roof of coal roadway is effectively in control under the mining pressure, which consequently verifies the validity of deformation and damage mechanisms of complex type of stress dilatancy expansion and the effectiveness of coupling support proposed in this paper, meanwhile it also provides the reference to the similar engineering geologic condition of coal roadway.