半煤岩巷道围岩破裂演化规律及控制技术

Failure evolution laws and control technology of roadway surrounding rock

针对半煤岩大巷围岩控制问题,以吕梁矿区某矿半煤岩运输大巷为研究对象,利用FLAC3D数值软件建立巷道计算模型,分析不同埋深时半煤岩巷道围岩的塑性区变化规律,并采用钻孔窥视仪对巷道围岩破裂范围进行精细探测。结果表明:围岩塑性区随着巷道埋深的增加而逐渐增大,尤其是巷道两帮及底板部位;大巷顶板0～1.8 m及4.9～5.1 m深度附近,裂隙极其发育,1.8～4.9 m深度范围内有许多微小的裂隙。根据数值模拟及现场探测结果,选择注浆锚索+注浆锚杆+金属网的全断面锚注支护方法。工业化实验结果证明此种方法可有效控制巷道的有害变形。该研究为其他类似条件下的巷道支护提供了参考。

Aimed at addressing surrounding rock control of half coal rock roadway, this paper drawing on the main haulage roadway of a colliery＇ s half coal rock in Luliang mining area describes the develop- ment of three-dimensional numerical model of roadway by a numerical simulation software FLAG3D, the a- nalysis of the laws governing the plastic zone of the roadway surrounding rocks occurring in the different buried depth, and the fine detection of failure radius of roadway surrounding rock by borehole imaging in- strument. The results suggest a gradual increase in the plastic zone of surrounding rocks, especially in two sidewalls and floor of the roadway, depending on the increase in buried depth; the occurrence of the ex- tremely well-developed fractures near surrounding rocks ranging from 0 m to 1.8 m and from 4. 9 m to 5. 1 m in depth; and the occurrence of many micro cracks from 1.6 m to 5. 1 m in depth. The numerical simu- lation and precise detection reveal the necessity of the whole section bolting-grouting support method consis- ting of grouting cable, grouting bolt, and metal mesh. The field monitoring shows that this method, capable of an effective restraint of the harmful deformation of roadways, could serve as reference guide for roadway support for similar conditions.