基于中长期微震时空特征的采动地压灾害风险分析

地压灾害风险动态评估与分析是制约深井安全高效开采的关键技术之一。针对某矿山千米以深开采地压灾害现状,通过分析矿山开采技术条件,设计并建立了深部地压灾害风险微震监测系统,开展了爆破定位标定试验,优化了重点监测区域系统速度模型,探究了矿山微震事件中长期时空分布规律,提出了基于微震监测的地压灾害风险分布特征。研究结果表明：采用纵波波速5400m/s、横波波速3200m/s,重点监测区域综合定位误差小于7.4m,满足矿山深部地压灾害风险监测需求；微震事件主要分布在施工及回采区域、隔离矿柱区域,微震活动与采动呈现正相关性；分析微震事件时序分布特征,II-1#矿带地压活动风险较大,红尖山易发生突发性、强度较大的地压事件。研究成果为该矿山深部地压灾害风险防控提供了数据支撑。

Risk Analysis of Mining-induced Ground Pressure Disaster based on Temporal and Spatial Characteristics of Medium and Long Term Microearthquakes

Dynamic risk assessment and analysis of ground pressure disaster is one of the key technologies to restrict safe and efficient of deep mining. Towards a lead-zinc deposit in deep mining ground pressure disaster situation, the mining technological conditions were analysed. The deep ground pressure disaster risk microseismic monitoring system was designed and setted up. Blasting tests were carried out to calibrate coordinates, therefor, the speed model of key monitoring area system was optimized. The medium and long term spatial and temporal distribution of microseismic events in mine is analyzed, and the risk distribution characteristics of ground pressure disaster based on microseismic monitoring were indicated. The results show that, the comprehensive positioning error of the key monitoring area is less than 7.4m with the p-wave velocity of 5,400m /s and s-wave velocity of 3,200m /s, which can meet the requirements of the risk monitoring of deep mine ground pressure disaster. Microseismic events are mainly distributed in construction and mining area and isolated pillar area, and there is a positive correlation between microseismic activity and mining activity. Based on the analysis of time series distribution characteristics of microseismic events, it can be concluded that iI-1 # ore belt has a high risk of ground pressure activities, and Hongjianshan is prone to sudden and strong ground pressure events. The research results provide data support for the risk prevention and control of deep ground pressure disaster in the Lead-zinc Mine.