孤岛工作面动压回采巷道平移变形力学机制及控制技术研究

A study on inward movement deformation mechanism and control technology of dynamic pressure gateway of island mining face

基于五阳煤矿7603孤岛工作面工程地质概况,进行现场调研并分析了运输巷掘进过程中出现两帮＂平移＂大变形的机理,得出巷道围岩变形机制是构造应力型（IIA）和重力型机制（IIB）＋弱层走向型机制（IIIBA）＋层理走向型机制（IIICA）＋随机节理型机制（IIIE）的复合变形力学机制;运用变形力学机制转化原理,提出＂携顶底,控两帮＂的支护思路,进而提出了新的支护方案。运用FLAC3D数值模拟对比分析了新方案与原方案的支护效果,新方案塑性区发育较原方案少106.5 m2单位面积;新方案顶底板移近量较原方案减少了65.4%,两帮移近量减少了78.9%,新方案可以有效控制围岩两帮平移大变形。工业性试验表明,运输巷道的顶底板最大移近量约250 mm,两帮最大移近量仅有350 mm,分别比原支护方案减小45.9%和79.2%;两帮锚杆受力在110-160 k N之间,锚索受力值约为300 k N,均在15 d前后趋于稳定,巷道围岩得到了有效控制,能够满足通风和安全生产需要。

Based on engineering geological survey of Wuyang Coal Mine 7603 island mining face, researchers have done field investigation and analyzed the mechanism of large deformation in the process of ＂Inward movement＂of two sides in the transportation tunneling, and have concluded that the roadway deformation mechanism is a compound deformation mechanism of Tectonic stress type and gravity deformation mechanism（IIAB）＋Structural deformation mechanism of weak layer effects（IIIBA）＋Bedding to the impact of structural deformation mechanisms（IIICA） ＋ Random jointed structural deformation mechanism（IIIE）. Using deformation mechanism transforming principle, this paper has proposed the supporting idea of ＂Relying on the top and bottom, controlling two sides＂, and put forward a new support scheme. Using Numerical simulation FLAC3 D this paper has also made a comparative analysis of the supporting effect of the new program with the original program, and has drawn the conclusion that the plastic zone development area of new program is 106.5 m2 per unit less than that of original program. The roof-to-floor convergence of new plan is 65.4% less than the original plan, and the convergence of two sides has reduced by 78.9%. According to these findings, the study has shown that the new scheme can effectively control large deformation of the surrounding rock. The industrial test has shown that the largest roof-to-floor convergence of transportation roadway is about 250 mm, and the maximum amount of two sides convergence is only 350 mm, respectively, 45.9% and 79.2% less compared with the original support scheme; the force of two anchors between 110-160 k N, and the force of anchor wire about 300 k N, have all stabilized at around 15 d, and the roadway surrounding rock has been effectively controlled, so that it could ensure ventilation and safety to meet production needs.