采动诱发断层带岩体劣化微震响应特征

Micro-seismic response characteristics of rock mass deterioration induced by mining in fault zone

以淮南矿区潘二矿12123工作面开采A组煤所面临的复杂断层带为研究对象,建立了微震监测系统,获取了构造发育区的微震活动数据,分析了断层带岩体劣化过程的微震事件分布及震源参数的响应特征,揭示了诱发微震响应的力学机制。研究结果表明:随回采与断层间存在的时空关系,微震事件表现出显著的时空强特征;累计能量、b值、能量指数以及累计视体积等随回采呈现阶段性变化,能够有效反映断层围岩的破坏状态;受回采线与结构面所构成的岩体“三角孤岛区”影响,应力区域性的集中分布所诱发的岩体破坏释放能量呈现时空迁移特性。

Taking the complex fault zone of group A coal mining in 12123 working face of Pan’er Mine in Huainan Mining area as the research object, a micro-seismic monitoring system was established to obtain the micro-seismic activity data in the structural development area, and the distribution of micro-seismic events and the response characteristics of source parameters during the deterioration of rock mass in the fault zone were analyzed, revealing the mechanical mechanism of the induced microseismic response. The results show that micro-seismic events show significant spatial and temporal characteristics with the relationship between mining and faults. The cumulative energy, b value, energy index and cumulative apparent volume change gradually with mining, which can effectively reflect the failure state of fault surrounding rock. Under the influence of“triangular isolated island area”of rock mass formed by mining line and structural plane, the energy released by rock mass failure induced by regional concentrated distribution of stress shows a space-time migration characteristic.