巷道动力失稳下围岩松动特征分析及支护参数选取

Analysis on surrounding rock loosening characteristics and selection of supporting parameters under dynamic instability of roadway

针对煤矿开挖导致的巷道动力失稳问题,为了提升煤矿巷道安全性,对巷道动力失稳下围岩松动特征分析及支护参数选取问题进行研究。给出乌东煤矿工程概况,在巷道设3个监测点,当动力失稳现象出现时,分析巷道围岩物理学性能,对煤矿巷道动力失稳下巷道表面位移进行监测,并进行实验分析,通过实验结果实现围岩支护参数选取。实验结果表明,动力失稳现象会导致围岩岩样的抗压强度变低;在距离工作面距离为90 m时,顶底移近与两帮收敛的变形速率最大;当监测点的监测日期逐渐上升,顶板的锚杆受力与锚索受力不断加大,其中锚索受力相对较高,而锚杆下帮受力要低于锚索上帮受力。按照实验结果设计支护参数,以防止围岩松动变形对巷道带来影响。

Aiming at the problem of roadway dynamic instability caused by coal mine excavation,in order to improve the safety of coal mine roadway,the analysis of surrounding rock loosening characteristics and the selection of supporting parameters under roadway dynamic instability are studied.The general situation of Wudong Coal Mine project is given.Three monitoring points are set in the roadway.When the dynamic instability occurs,the physical properties of roadway surrounding rock are analyzed,the roadway surface displacement under the dynamic instability of coal mine roadway is monitored,and the experimental analysis is carried out.Through the experimental results,the selection of surrounding rock supporting parameters is realized.The experimental results show that the dynamic instability phenomenon will lead to the lower compressive strength of surrounding rock samples.When the distance from the working face is 90 m,the deformation rate of top and bottom moving close and two sides converging is the largest.When the monitoring date of the monitoring point rises gradually,the stress of the anchor bolt and anchor cable of the roof increases continuously,in which the stress of the anchor cable is relatively high,and the stress of the lower side of the anchor bolt is lower than that of the upper side of the anchor cable.The supporting parameters are designed according to the experimental results to prevent the influence of surrounding rock loosening and deformation on the roadway.