Analysis on regional microseism law of coal pillar in mining block and prevention and control technology of mine pressure bum p

An analysis was conducted on the regional microseism activity law of the coal pillar in the mining block and could provide the basis to prevent and control the mine pressure bump.Based on the-1 025 m West First Downill Mining Block in Zhangxiaolou Mine as a case,the microseism frequency rate and energy concentration ratio were established and the microseism space actvity in the coal illar zone of the mining blok and the whole mining block was analyzed. The space distribution of the microseism events was applied to analyze the mining dynanic disturbance speed and scope of the coal mining face as well as the microseism distribution and the large energy microseism event evolution process ofthe coal pillar key region in the mining block. The results showed that the microseism events were concentrated distributed existed in the coal plar region of the mining block. The microseism frequency rate concentration ratio in the coal pilar region was 3.25 and the microseism energy concentration ratio was 3.37.The mining speed of the coal mining face would have a posiive relationship to the microseism frequency rate and energy of the coal pillar in the mining block. The advance influence distance of the coal mining face was 166 m in average and the max infuence distance was 228 m. The hysteresis infuence distance in the mining goaf was 90 m in average and the max hysteresis infuence distance was 125m.T'he microseism was firstly occurred in the strong shearing zone with a far distance to the calpillar core zone. With the mining operation of the coal mining face,when the stress of the core region reached the support limithe large energy microseism event would be occurred and the mine pressure bump danger would be increased. with the practices of the energy dissipation and bump buffer technology,the dynamic disaster was successfully eliminated and a safety mining was realized.