基于光纤微震监测的底板破坏时空演化规律研究

Research on Spatiotemporal Evolution Law of Bottom Plate Failure Based on Fiber Optic Microseismic Monitoring

随着煤炭开采深度的增加,采煤工作面将面临严重的高承压水威胁,以淮南矿区受底板承压水威胁的潘二煤矿11023采煤工作面为工程背景,采用高灵敏光纤微震监测系统对工作面底板破坏时空演化规律进行监测分析。结果表明,工作面底板微震事件数量主要集中在煤层底板0~20 m内;微震事件数量与开采活动速度有明显的相关性,工作面退尺进度越大,微震事件数量越多;在断层和煤层变薄异常区附近,微震事件的数量增多和强度增大;工作面初采期间应力集中释放,底板受采动影响破坏较深。研究结果可为工作面底板水害防治和工作面推进速度的优化提供技术支撑。

With the increase of coal mining depth,the coal mining face wll face a serious threat of high pressure water.Taking the 11023 coal mining face of Pan'er coal mine in Huainan mining area,which is threatened by floor pressure water,as the engineering background,a highly sensitive fiber optic microseismic monitoring system was used to monitor and analyze the spatiotemporal evolution law of the floor failure of the working face.The results indicate that the number of microseismic events on the working face floor was mainly concentrated within the range of 0-20 m of the coal seam floor;there was a clear correlation between the number of microseismic events and the speed of mining activities.The greater the progress of mining face retreat,the more microseismic events there were;near the abnormal areas of faults and coal seam thinning,the number and intensity of microseismic events increased;during the initial mining period of the working face,the rock pressure stress was concentrated and released,and the bottom plate was deeply damaged by mining.The research results can provide technical support for the prevention and control of water damage on the bottom plate of the working face and the optimization of the advancing speed of the working face.