冲击矿压发生机制及矿震规律分析

Analysis on Rock Burst Occurrence Mechanism and Mine Tremors Distribution Law

针对具有向斜构造和坚硬顶板等典型地质特征的工作面,基于SOS微震监测技术,分析了鹤岗兴安煤矿两次冲击前矿震的时空分布规律及其冲击发生机制。研究表明:2012年6月26日冲击前,底板发生大能量矿震较少,而工作面见方阶段顶板岩层断裂破坏产生的矿震多、能量大,冲击动载起到了主导作用,属于动载主导冲击模式;2012年10月15日冲击前,矿震主要集中分布在向斜轴部区域,顶板岩层破断产生的动载对冲击矿压有触发作用,冲击动载起到了诱发作用,属于静载主导-动载诱发模式;同时,进风巷较回风巷弯曲半径小,曲率大,应力集中程度更高,使此次冲击发生在进风巷。

Aiming at te working face with syncline structure and hard roof,time and space distribution regularity of mine tremors before two rock burst and their occurrence model were studied based on SOS micro- seismic monitoring technology.Results showed that,less mine tremors occurred in the seam floor before‘26th Jun＇rock burst. While the crack of seam roof generated more mine tremors with larger energy,in which dynamic load played a leading role,the rock burst was dynamic load dominant mode. Mine tremors mainly distributed in the area of the syncline axis before ‘15th Oct＇rock burst. Dynamic load caused by the crack of seam roof has the triggered effect in this rock burst,which belonged to the static load dominant- dynamic load induced model. Compared to return airway,the intake airway had smaller bending radius,larger curvature and higher stress concentration,which caused the rock burst in intake airway.