巨厚覆岩下协调分层开采矿震活动规律研究

Study on seismic activity law of coordinated layered mining under huge thick overlying rock

为研究巨厚覆岩对厚煤层协调分层开采工作面的影响,以孟加拉国Barapukuria煤矿1310工作面为研究对象,对工作面一、二、三分层回采区域的矿震活动规律进行了研究。结果表明:1310工作面一分层回采区域巨厚覆岩在剖面上为“T”型结构,在平面上为“矩形”块段垮落,对工作面的影响特征为低静载、强动载。根据微震活动分析,从一分层至三分层回采区域内10^(3)J级矿震事件能量、频次占比依次降低,且二分层回采区域的矿震强度、活动性均弱于一分层回采区域,表明巨厚覆岩下,处于下位分层工作面的矿震能量与频次会向低能量事件转移,冲击危险性能够得到有效降低。

In order to study the influence of huge thick overlying rock on the working face of coordinated layered mining of thick coal seam,taking the 1310 working face of Barapukuria Coal Mine in Bangladesh as the research object,the law of mine seismic activity in the first,second and third layered mining areas of the working face was studied.The results showed that the thick overlying rock in the stratified mining area of the 1310 working face had a "T"-shaped structure on the section and a "rectangular" block collapse on the plane.The influence on the working face was characterized by low static load and strong dynamic load.According to the analysis of microseismic activity,the energy and frequency proportion of 10^(3)J mine earthquake events in the mining area from the first layer to the third layer decreased in turn,and the intensity and activity of the mine earthquake in the second layer mining area were both weaker than one point.The layer mining area showed that under the huge thick overlying rock,the mine shock energy and frequency in the lower layered working face would be transferred to low-energy events,and the impact risk could be effectively reduced.