煤矿大断面吊装硐室围岩破坏机理及控制

Mechanism and Control of Surrounding Rock Failure for Assembling Cavern in Large Fracture Surface of Coal Mine

为探究大断面硐室围岩稳定性及控制技术,采用UDEC数值计算方法研究了板集矿大断面吊装硐室,得出随着断面增大,矩形硐室帮部由“不稳定三角块”滑移破坏向“X”型共轭破坏转化。半圆拱硐室以帮部的“不稳定三角块”破坏为主,巷道变形规律:两帮水平移近量>两帮下沉量>顶板下沉量>底臌量。从而提出采用巷道表面喷浆、巷帮注浆配合高强、高预紧力锚杆索联合支护的方式控制大断面硐室变形。通过工程实例反馈,大断面硐室变形得到良好控制。

In order to explore the stability of assembling cavern in large fracture surface and its control technology,UDEC numerical calculation method is used to study the assembling cavern in large fracture surface of Banji mine.It is concluded that with the increase of fracture surface,the sliding failure of rectangular chamber side changes from“unstable triangular block”to“X”type conjugate failure.The semi-circular arch chamber is mainly destroyed by“unstable triangle block”on the side.The deformation law of roadway is:horizontal convergence of two sides>sinkage of two sides>sinkage of roof>floor heave.Therefore,it proposed that to control the deformation of assembling cavern in large fracture surface by means of combined support of shotcrete on roadway surface,grouting at roadway side and bolt cable with high strength and high preload.Based on feedback of engineering projects,the deformation of assembling cavern in large fracture surface is well controlled.