红阳三矿保护层开采卸压防冲保护效果分析

Analysis on Protection effect of Pressure Relief and impact Prevention in protective layer Mining of Hongyang No.3 Mine

为研究保护层开采对被保护层卸压效果的影响,针对红阳三矿1208工作面和1204-2工作面实际地质条件,进行有无保护层开采效果防冲效果分析,通过微震数据、微震事件平面与垂向分布特征以及微震事件频次与能量时间序列分析和覆岩动态破断规律对比分析,结果可知:无保护层开采的1208工作面顶板完整,而保护层开采破坏顶板完整性,大幅度降低了被保护层开采过程中顶板和煤层中微震事件,降低了工作面发生冲击的危险性,同时保护层开采对被保护层的应力有降低作用和卸压作用,且无保护层开采的工作面出现周期性跨段,有保护层开采的工作面不发生周期性跨断,工作面来压小,冲击危险性降低。研究成果为矿区煤层区域化防冲措施选择提供了工程数据基础。

In order to study the influence of protective layer mining on the pressure relief effect of the protected layer,the impact prevention effect of mining effect with or without protective layer is analyzed according to the actual geological conditions of the 1208 working face and 1204-2 working face of Hongyang No.3 Mine.Based on the microseismic data,the plane and vertical distribution characteristics of microseismic events,the time series analysis of the frequency and energy of microseismic events,and the comparative analysis of the dynamic breaking law of overburden rock,the results show that:The roof of 1208 working face without protective layer mining is complete,while the protective layer mining damages the roof integrity,greatly reduces the microseismic events in the roof and coal seam during the mining process of the protected layer,and reduces the risk of the impact of the working face.At the same time,the protective layer mining has the effect of reducing the stress of the protected layer and relieving pressure,and the working face without protective layer mining appears periodic span.There is no periodic break in the working face with protective layer,and the working face is less compressed and the impact risk is reduced.The research results provide engineering data basis for the selection of regional anti-scour measures of coal seam in mining area.