深部采场进路开采顶板稳定性分析与支护设计

为降低深部矿体开采中冒顶事故的发生概率，确保井下安全开采，采用Q系统分级法、RMR岩体分类和BQ分级法对矿区岩体进行质量评价，结合块体理论和三维有限元分析进路开挖后顶板的稳定性。研究表明:部分岩体在进路开挖后顶板处出现较大拉应力集中，抗拉稳定性降低，极有可能出现冒顶事故。针对这类不稳定岩体，提出永久巷道采用锚喷支护，临时巷道采用锚杆穿带支护；并运用悬吊理论、组合梁理论、屈服强度理论和安全系数法分析支护条件下进路顶板的稳定性，优化支护结构参数。通过振弦式锚杆应力计收集现场未支护巷道与支护巷道轴向力，得出该支护设计对开挖后岩体变形起到了明显改善作用。

Roof stability analysis and support design in drift mining of deep stope

In order to reduce the occurrence probability of roof fall accident in the mining of deep orebody and ensure the safety of underground mining, the quality of rock mass in the mining area was evaluated by using the Q system grading method, RMR rock mass classification method and BQ grading method, and the stability of roof after drift excavation was analyzed combining with the block theory and three-dimensional finite element analysis. The results showed that partial rock mass appeared the larger tensile stress concentration at the roof after the drift excavation, and the tensile stability decreased, so the roof fall accident was very likely to occur. Aiming at such unstable rock mass, it was proposed that the permanent roadway should adopt the bolt-shotcrete support, while the temporary roadway should adopt the bolt and belt support, and the stability of drift roof under the support conditions should be analyzed by using the suspensory theory, the composite beam theory, the yield strength theory and the safety factor method, so as to optimize the parameters of support structure. The axial forces of unsupported roadway and supporting roadway in the field were collected by the vibrating wire bolt stress meter, it showed that this support design played an obvious improvement effect on the deformation of rock mass after the excavation.