Case Study on Dynamic Identification of Overburden Fracture and Strong Mine Pressure Mechanism of Isolated Working Face Based on Microseismic Clustering

Strong mine pressure has a great impact upon the safety production of coal mines. Microseismic information provides more advanced technical means for overburden fracture dynamic identification and mechanism research, since it contains rich on rock sources. In this study, isolated LW8102 working face in Tongxin Mine was investigated order to propose spatio-temporal microseismic event data analysis method based k-means clustering algorithm. This algorithm can handle fractures constrained by spatiotemporally discrete distributions events. provided extension process distribution pattern overburden: eight extensions were formed overburden. each extension, vertical connected low high layers LW8103 goafs, through goafs their high, middle, levels. Some had that form closed loop structure. fracture, there tendency one or two stratum fail first, then extend both sides. The propagation followed certain temporal sequence, reflected primarily forms: firstly, as extended layer, initial rupture space spreading; secondly, first broke, until intersected with expansion fracture. By matching responded support resistance, we analyzed at face. Through level found be primary cause occurrence mining pressure. It precisely placed formation multiple adjacent 110 m from floor, triggering simultaneous instability motion lower multi-layer rock; main reason phenomenon strong Meanwhile, 80 floor large