孤岛综放工作面强烈的动压显现使得其发生冲击地压的可能性大大增加,通过运用微地震和电磁辐射综合监测手段分析孤岛综放工作面两次强动压显现事件,获得了工作面煤体发生冲击地压前后能量积聚与释放规律及相应微震和电磁辐射监测数据变化规律,认为工作面煤体发生冲击地压前一般存在一个短暂的能量积聚期,在能量积聚期内微震系统监测到的微震事件的次数和总能量均较少,同时能量积聚期内煤体电磁辐射强度值和脉冲数均持续升高。将工作面微震事件的沉默期以及煤体电磁辐射强度值、脉冲数的持续升高期作为冲击地压的综合前兆信息,并将其转换为量化的预警参数和指标,建立了工作面冲击地压多参数预警方法。现场实践表明,危险识别与灾害预警效果良好。
The strong dynamic pressure manifestation on the island fully mechanized caving face largely increases the possibility of rockburst. Two strong dynamic pressure manifestation events of the island fully mechanized caving face are analyzed by making use of microseismic and electromagnetic radiation monitoring. The law of energy accumulation and release in coal, as well as the monitoring data variations of microseismic and electromagnetic radiation, which pre and post rockburst, are obtained. The coal of working face generally has a short energy storage time before the rockburst. The number of microseism events and the total energy of microseism events are few in this period, which is monitored by the microseism system. And at the same time the coal electromagnetic radiation intensity value and the pulse number continually increased during this period. The microseism event silence period of working face as well as coal electromagnetic radiation intensity value and pulse number continual ascension period can be seen as rockburst precursor information. By transforming these precursor information into quantitative early warning parameters and index, the method of working face rockburst multiparameter early warning is proposed. Finally, the engineering practice shows that this method is effective.