受上覆采空区影响的巷道群稳定性控制研究

发布时间：2019-01-07 17:04

【摘要】：近距煤层下行开采中,因受上层煤采空区及煤柱的影响,下层煤巷道的应力环境及围岩破坏机理均发生复杂变化。采用理论分析、数值模拟与工程应用的综合方法,研究下层煤应力分布规律、巷道群的变形破坏机制及稳定性控制对策。研究表明:受上覆采空区释压作用影响,其下方巷道围岩应力集中较小、巷道较为稳定;受煤柱压力传递影响,煤柱下巷道围岩垂直应力急剧升高,应力集中系数达3.84,巷道两帮及肩部大范围压剪破坏,最终导致巷道整体失稳;煤柱下高应力区巷道宜采用拱形断面,增加支护强度与锚固预应力,顶板锚索(杆)向巷道两肩角倾斜布置,使支护体系与围岩塑性破坏区相互耦合并得到共同强化。在支护优化后巷道顶板下沉量减小42.8%,锚杆、锚索实测工作载荷分布合理,实现了对煤柱下近距煤层巷道的安全有效控制。
[Abstract]:Due to the influence of the upper coal goaf and pillar, the stress environment of the lower coal roadway and the failure mechanism of surrounding rock are all changed. In this paper, the comprehensive method of theoretical analysis, numerical simulation and engineering application is used to study the stress distribution law of the lower coal, the deformation and failure mechanism of the roadway group and the stability control strategy. The results show that the surrounding rock stress concentration is small and the roadway is more stable because of the pressure release from the overlying goaf. Influenced by the pressure transfer of coal pillar, the vertical stress of surrounding rock under coal pillar increases sharply, the stress concentration factor reaches 3.84, and the two sides of roadway and shoulder are destroyed in a wide range, which leads to the overall instability of roadway. The arch section should be adopted in the roadway with high stress under the coal pillar, the support strength and anchor prestress should be increased, and the roof anchor cable (rod) should be inclined to the two shoulders of the roadway, so that the support system and the plastic failure zone of surrounding rock can be coupled and strengthened together. After the optimization of support, the roof subsidence of roadway is reduced by 42.8 and the measured load distribution of anchor rod and anchor cable is reasonable, which realizes the safe and effective control of coal pillar coal seam roadway.
【作者单位】：太原理工大学矿业工程学院;中国矿业大学深部岩土力学与地下工程国家重点实验室;太原理工大学采矿工艺研究所;
【基金】：国家自然科学基金项目(51274145) 深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK1311) 山西省自然科学基金项目(2015011066)
【分类号】：TD322

【参考文献】