二次采动巷道锚杆(索)支护效应分析

Analysis of anchor bolt and cable supporting effect in roadway influenced by the secondary mining process

采用数值模拟和现场监测的方法分析了14103麻家梁煤矿辅运副巷在经历二次采动应力的影响下,巷道锚杆(索)的支护效应。数值模拟分析14103辅运副巷采用高预应力支护可有效改善巷道支护应力场;现场监测发现锚杆、锚索杆体应力受14102工作面回采影响先急剧增加后趋于稳定,再经历14103工作面回采影响虽部分杆体应力有所下降,但仍能保持有效支护作用;14103辅运副巷浅部锚杆索支护范围内的3 m处围岩始终保持较强的承载能力,较深部5 m处围岩已进入塑性区,深部8 m和10 m围岩始终具有较强的承载能力。辅运副巷经历二次采动影响后,顶底板移近量为390 mm,两帮移近量为280 mm。

The supporting effect of anchor bolts and cables in 14103 auxiliary transport roadway influenced by the secondary mining in Majialiang Coal Mine was analyzed by the methods of numerical simulation and field monitoring.The results showed that high prestressed supporting could improve the stress field of roadway supporting in effect;it was found by the field monitoring that the stresses of anchor bolts and cables first increased sharply and then tended to be stable influenced by 14102 face mining process,then the stresses of some slightly decreased while the supporting kept effective during the 14103 face mining process.Within the range of anchor bolts and cables supporting,the surrounding rocks at 3m from the wall of 14103 auxiliary transport roadway always kept rather strong bearing capacity,and the surrounding rocks at 5 m were nearly into the plastic zone,and the surrounding rocks at 8 m and 10 m always had rather strong bearing capacity.After the secondary mining influence,the distance between the roof and floor decreased 390 mm and the distance between two sides decreased 280 mm.