微地震监测技术在回采工作面矿压显现规律中的应用

Application of micro seismic monitoring technology in strata-pressure behavior law for coal mining face

工作面回采导致上覆岩层破坏,上覆岩层的破坏与煤矿顶底板突水、冲击地压、煤与瓦斯突出等事故发生密切相关,对回采工作面矿压显现规律的研究是保障煤炭安全开采的关键之一。回采工作面在覆岩破坏过程中,由于应变能的释放,产生相应强度较弱的地震波(微地震波)。微地震监测技术能够实现实时动态三维空间的整体监测。对鲁西煤矿3上107工作面回采过程中覆岩破坏产生的微地震事件进行了监测,通过对监测到的微地震事件定位计算,证实微地震发展演化与采场覆岩破坏密切相关。鲁西煤矿3上107工作面矿压显现规律的微地震监测分析表明,顶板来压时微地震事件数达到高峰,顶板的来压完成时微地震事件数下降,据此得出3上107工作面基本顶来压步距为23.3 m。与通过现场实测得出的基本顶来压步距24.3 m基本吻合,说明采用微地震监测技术研究回采工作面显现规律是可行的,从而为回采工作面矿压显现规律的研究提供了一种新的技术途径。

Coal mining causes the rapture of overburden strata of coal seam.The rapture of overburden strata of coal seam is closely related to the occurrence of water abruption,shock earth pressure,coal and gas burst and so on.So the research of strata-pressure behavior law is one of the key coal mining safety protection.In the forming process of the failure of overlying strata,because of the releasing of strain energy,the corresponding wake seismic waves(microseismic waves)will be induced in the same time.Three dimensional monolithic observation can be realized by microseism monitoring technology.In this paper,it monitored micro seismic which is caused by fracturing of the overburden strata in 3up 107 coal face extraction of Luxi Coal Mine.The close relationship between evolvement of micro seismic and fracturing of the overburden strata was proved by location of the monitored micro seismic events.Through the microseism monitoring analysis of strata-pressure behavior law in 3up 107 coal face of Luxi Coal Mine,it was obtained that,the microseismic events reach the peak when the roof weighing occurs,and the microseismic events decrease with the completion of roof weighing.According to this roof weighting step distance of 3up 107 coal face,main roof weighting step was determined as 23.3 m,which is almost the same as 24.3 m from ground pressure observation.Microseism monitoring technology was proved to be available in studying the strata-pressure behavior law of coal face.This provides one new technical method to study strata-pressure behavior law of coal face.