煤巷大厚度泥岩顶板围岩裂隙演化规律数值试验研究

Numerical Testing Study on Crack Development Law of Surrounding Rocks of a Coal Roadway with Great-thick Mudstone Top Roof

运用数值试验系统,研究了煤巷大厚度泥岩顶板围岩裂隙萌生-扩展-贯通-破坏的演化规律。根据围岩裂隙的分布和演化,结合地质力学与环境条件,揭示出大厚度泥岩顶板垮落是由于煤帮上方的剪张裂隙及顶板上方的水平裂隙所形成的裂隙拱造成的,提出大厚度泥岩顶板煤巷支护的三个主要特点:及时封闭围岩、加大锚杆支护系统刚度、锚杆(索)沿裂隙方向斜向布置。研究结果有利于了解巷道围岩内部破裂的产生和发展规律,为巷道锚固方案的选择和锚固参数的优化提供了依据,可为类似条件矿井的支护提供理论依据与应用性指导。

The evolution law of the crack generation-extension-connection-failure in the surrounding rocks of a coal roadway with great-thick mudstone top roof was investigated in the paper by using numerical method.On the basis of crack distribution and evolution,and the geological mechanics and environmental conditions of roadway surrounding rock,it was indicated that the great-thick mudstone top roof collapse is caused by the crack arch,resulted from shearing and tension crack above the two roadway walls and horizontal crack in the roadway top.Three main features to support the coal roadway with great-thick mudstone top roof were proposed,such as enclosing in time,enhancing the stiffness of the bolting supports system and disposing the bolts（cable bolts） along the crack.The research results are useful for understanding the occurrence and development law inside the surrounding rocks,and applicable as the basis of selection of bolting scheme of roadway and optimization of bolting parameters.They also provide a theoretical and practical guidance not only for this mine but also for other similar mines.