基于锚固应力叠加控制原理的多层支护数值模拟实验研究

Experimental study on numerical simulation of multi-layer support based on principle of anchor stress superposition control

随着开采深度增加,回采巷道锚杆支护的难度越来越大,该文基于薛湖煤矿29020机巷围岩赋存地质条件,实验室测试了巷道围岩物理力学参数,现场实测了巷道围岩松动圈,提出了锚固应力叠加控制原理。在此基础上进行了锚杆支护参数的理论计算,并采用数值模拟优化了锚网索支护参数,在薛湖煤矿29020机巷进行了现场应用,取得了较好的技术经济效益。研究结果表明:29020机巷顶板存在80~100 cm的松动圈;采用“锚杆+短锚索+长锚索”多层支护形式可更好地保证围岩稳定性,并计算得到锚杆合理长度为2.4 m,间排距为0.7 m×0.8 m,长锚索8.3 m,短锚索5.5 m,间排距为1.4 m×3.2 m;巷道顶板、两帮位移量10~20 mm,锚杆、短锚索、长锚索端锚力分别为50~100 kN、100~150 kN、100~200 kN,29020机巷围岩稳定性得到了较好控制。

With the increase of mining depth,it is more and more difficult to support the roadway with bolts.Based on the geological conditions of the surrounding rock of the 29020 machine roadway in Xuehu Coal Mine,the physical and mechanical parameters of the roadway surrounding rock are tested in the laboratory,the loose ring of the roadway surrounding rock is measured in the field,and the principle of anchor stress superposition control is proposed.On this basis,the theoretical calculation of the anchor support parameters is carried out,and the anchor mesh and cable support parameters are optimized using numerical simulation,it has been applied in the 29020 machine roadway of Xuehu Coal Mine and achieved good technical and economic benefits.The results show that there is 80~100 cm loose ring on the roof of 29020 machine roadway.The multi-layer support form of“bolt+short anchor cable+long anchor cable”can better ensure the stability of surrounding rock,and the reasonable length of the bolt is 2.4 m and the row spacing is 0.7 m×0.8 m,8.3 m long anchor cable,5.5 m short anchor cable,1.4 m spacing×3.2 m.The displacement of roadway roof and two sides is 10~20 mm,and the anchor force of bolt,short anchor cable and long anchor cable end is 50~100 kN,100~150 kN and 100~200 kN respectively.The stability of surrounding rock of 29020 machine roadway is well controlled.