大安山矿轴10下槽煤层回风巷道让压支护模拟与试验

Simulated and experimental research of high-stress yielding support at the return airway of the 10-th coal shaft groove in Daanshan Mine

大安山矿已经进入深部开采阶段,高应力、大变形巷道支护问题日益突显。为维护矿井深埋巷道稳定,引进高强让压锚杆支护技术控制深埋巷道大变形。根据轴10下槽煤层回风巷道实际情况,运用FLAC3D软件数值模拟高强锚杆和高强让压锚杆支护条件下围岩响应情况,并在现场展开让压支护技术试验。对比分析模拟与试验结果表明,数值仿真与现场实际较为一致,高强让压锚杆支护技术能够显著改善深埋巷道应力状态,有效控制深埋巷道大变形,保证矿井安全生产。

This paper is aimed at a simulated and experimental research of pressure-yielding support at the return airway of the10-th coal shaft groove in Daanshan Coal-Mine,which is known entering its deep mining stage. As the result,there appear more and more problems of high stress and frequent deformation of roadway support for a coal mine to enter such a stage. In hoping to maintain the stability of deep roadway coal transport and transfer in the mine,high-strength yielding bolt-supporting technology has to be introduced into the control process hereby. What is more,it is also necessary to fix a yielding link between highstrength bolt trays and the nuts to allow for the relief of their press of surrounding rocks to some extent. Therefore,we have to resort to a software known as FLAC3 Dto simulate the stress and the deformation response of the surrounding rocks under the said conditions. And,finally,the simulation results of this paper show that,as compared with the high-strength bolt support,the surrounding rock deformation of the roadways when the high-strength yielding bolt support is used has obviously decreased. According to the actual state of return airway of the shaft groove of 10-th coal,the roof subsidence,the floor heave and convergence of the both sides have been found decreased by 40%, 40. 4%,61. 2%,respectively. With the significant decrease of the highstrength yielding bolt stress,the reducing range covers an area of43. 2% of the total. Seeing the favorable results,we have also conducted an on-site stress-yielding support design experiment,and managed to keep regular monitoring activities over the experiment results,which indicate that,as compared with the highstress yielding bolt support with regular support,it has been made possible to reduce the relative decline of the roadway roof subsidence by 58. 6% and the relative deformation of two sides by51. 8%. A comparison made as to the simulation analysis with the experimental results shows that the numerical simulation results prove to be consistent with the actual situation. Thus,a conclusion can be made that the high-strength yielding bolt support technology is in a position to contribute to the improvement of the deep roadway transportation,whose effective control helps to ensure the deep-layer mining safety.