深井煤巷卸压孔与锚网联合支护的模拟与实践

Numerical Simulation and Industrial Test for Combined Support of Pressure-Relief Boreholes with Bolt-Mesh in Deep Coal Tunnel

为了解决深井高应力煤巷支护成本与支护效果之间的矛盾,提出并研究了卸压孔与锚网联合支护技术.结合一个工程实例,采用数值方法模拟和分析了钻孔卸压的作用机理、巷道围岩动态损伤破坏发展以及围岩中应力场重新分布的过程.研究表明:合理布置的卸压孔可以引起巷帮围岩发生结构性预裂破坏,从而使围岩内高应力向深部转移;卸压孔和锚网联合支护改善了围岩中的应力环境,改变了围岩破坏的时空次序,对控制围岩变形和破坏具有突出的优越性.将模拟结果用于指导具体的施工,不仅控制了围岩的变形,而且降低了材料消耗,取得了较好的综合效益.

A combined support of pressure-relief boreholes with bolt-mesh was proposed and studied to balance the supporting cost and the supporting effect. The mechanism of stress release by drilling boreholes, the development of the dynamic damage and destruction of the surrounding rock-mass and the redistribution of the stress field around the tunnel were simulated and analyzed. The result shows that the pressure-relief boreholes of reasonable distribution can lead to a pre-failure of the structure of surrounding rock-mass. Therefore, the high stress will be transferred to the deep rock-mass. After the operation of pressure-relief boreholes with boltmesh, the stress environment in the surrounding rock-mass was improved and the spatio-temporal order of the destruction of the surrounding rock-mass was changed. Therefore, the support-combination has prominent superiority for controlling the deformation and destruction of the surrounding rock. When the technology was applied in practice, not only the deformation of the tunnel was well controlled, but also the cost of supporting materials was reduced, resulting in a dramatic economic effect.