基于微震法的煤矿冲击危险性监测研究

Rock burst danger monitoring based on microseismic method

强矿震发生前的大量矿震信号是评价冲击矿压危险的重要信息源。本文以平十一矿安装的SOS高精度微震监测为基础,利用主成分分析技术构建了震源集中程度指标值,与震源能量和震动频次的现场统计研究结果表明:1)强矿震主要集中在煤层群多工作面停采线包围的煤柱叠加群内;2)强矿震发生前,震源能量首先经历1个震动活跃期,之后出现较明显的下降阶段,当震动频次维持在较高水平时,具有强矿震危险性;3)震动次数越多,震源集中程度指标值越小,发生强矿震的可能性就越大。基于3个参量的前兆规律,针对平十一矿建立了冲击危险性打分标准,并利用累加法进行冲击危险的整体评价,结果表明该评价体系能够及时指导现场防治降低冲击危险性。

Massive mining-induced seismic events may appear before the occurence of strong tremor, which is important information for the evaluation of rock burst danger. In this paper, based on the seismic monitoring by SOS Seismological Observation System installed in No.10 Coal Mine of Pingdingshan Mining Area, the concentration index of seismic source was constructed by the principal component analysis technique, to study the distribution characteristics of seismicities, and the variation rules of seismic energies and events numbers were also analyzed. The results show that： 1） Strong tremors mainly concentrated in the coal pillar regions formed by stop lines of multi coal faces in coal seam group; 2） Before strong tremor happened, the total energy of seismic events may be active firstly, then presents obvious decreasing trend, while the event numbers always keep in a relatively high level; 3）The larger the event number, and the smaller the concentration index of seismic source, the higher occurrence possibility of strong tremor. Based on the precursory rules of above parameters, the grading standard system of burst danger for No.10 Coal Mine of Pingdingshan Mining Area were built by accumulation method to evaluate the burst danger level. Application results show that the evaluation system can be successfully used to evaluate rock burst danger.