基于地应力测试的高地应力巷道破坏机理及控制

Failure Mechanism and Control of High In-situ Stress Roadway Based on In-situ Stress Test

基于高地应力巷道理论研究和现场实践,针对平山煤业轨道大巷高地应力条件下巷道变形破坏严重问题,提出了应用声发射Kaiser效应测试原理,通过探究该煤矿轨道大巷地应力分布情况,结合实验室岩石物理力学性质测试及现场窥视,得出轨道大巷围岩大变形的主要原因:(1)巷道处于高应力区,且大巷与最大水平主应力夹角大;(2)大巷两侧采空,属于跨采巷道,导致大巷应力集中;(3)巷道围岩岩石强度低,且围岩裂隙较发育;(4)巷道上部工作面多次采动影响,采动应力集中。研究发现,与无支护相比,采用注浆锚索支护后,巷道顶板下沉量减小了82.5%,巷道底鼓量减小了63.6%,两帮移近量减小了79.2%,说明通过锚注喷支护,改善了围岩条件,极大地减小了围岩位移量。

Based on the theoretical research and field practice of high in-situ stress roadway,aiming at the serious problem of roadway deformation and failure under high in-situ stress condition of track roadway in Pingshan coal industry,the Kaiser effect testing principle of acoustic emission was proposed to explore the in-situ stress distribution of track roadway in this coal mine.Combined with laboratory rock physical and mechanical properties testing and field peeping,the main reasons for large deformation of surrounding rock of track roadway are as follows:(1)the roadway is in high stress area,and the angle between the roadway and the maximum horizontal principal stress is large;(2)mined-out on both sides of the roadway belongs to cross-roadway,which leads to the concentration of roadway stress;(3)the rock strength of roadway surrounding rock is low,and the cracks in surrounding rock are well developed;(4)the upper working face of roadway is affected by mining for several times,and the mining stress is concentrated.The study found that compared with no support,grouting anchor cable,roadway roof subsidence decreased by 82.5%,roadway floor heave volume decreased by 63.6%,two sides closer to decrease by 79.2%,through the anchor injection supporting,the condition of surrounding rock is improved,and the displacement of surrounding rock is greatly reduced.