摘要
Abstract
In response to the evolution characteristics of overlying rock fractures caused by repeated mining in the weak o-verlying coal seam of Jiangzhuang Coal Mine,a combination of laboratory testing,on-site measurement,and numerical simu-lation was used to analyze the lithology and mechanical properties of the overlying rock layer.The development of water con-ducting fractures was explored,and a numerical calculation model and similar experimental model for repeated mining were established to study the movement and deformation characteristics of overlying rock caused by repeated mining.The results show that the overlying rock of the roof is mostly sandstone and mudstone,with moderate rock quality,belonging to typical weak overlying rock;The development height of the overlying rock water conducting fracture zone is 68～82 meters,and the fracture mining ratio is 17.0-20.5.The height of the water conducting fracture zone is about 20.5 times the mining height;After repeated mining,the horizontal and vertical stress values of the overlying rock increase,especially for the overlying rock located in the upper part of the goaf.The horizontal stress increases significantly,and the original fractures and separa-tion layers develop again,leading to an increase in the height of the water conducting fracture zone.关键词
软弱覆岩/导水裂隙/重复采动/数值模拟/现场实测Key words
weak overlying rock/water-conducting fracture/repetitive mining disturbance/numerical simulation/field meas-urement分类
矿山工程
