留顶煤大断面巷道围岩失稳机理及支护对策研究

Study on instability mechanism and supporting measures of surrounding rock of large section roadway with top coal

针对余吾煤业S1203留顶煤沿底掘进大断面巷道围岩控制困难的问题,运用FLAC3D数值模拟软件对巷道围岩塑性区和主应力分布特征进行分析,得到了留顶煤大断面巷道围岩失稳机理。在此基础上提出了留顶煤大断面巷道支护原则,根据该原则,决定采用机载高阻力临时支护和高预紧力锚杆锚索支护对策,并应用于工程实践。数值模拟和现场实测均表明,该方案支护效果良好,可有效保持巷道稳定。

In view of the difficulty of controlling the surrounding rock of large section roadway along the bottom of the S1203 face,the FLAC3D numerical simulation software was used to analyze the distribution characteristics of the plastic zone and the principal stress of the surrounding rock,and the instability mechanism of the surrounding rock in the large section roadway was obtained.On this basis,the principle of supporting the roadway with roof coal was put forward.According to this principle,the combined supporting measures of onboard temporary support with high resistance and bolt-cable anchor with high pre-tightening were adopted and applied to engineering practice.Both numerical simulation and field measurement showed that the proposed method was effective and could maintain the stability of the roadway.