摘要
针对22116工作面弱冲击倾向性的特点,采用液压支架监测,揭示主关键层破断对工作面周期来压的影响,并结合微震与电磁辐射耦合监测,研究回采工作面微震与电磁辐射耦合事件的分布特征和分析主关键层断裂跨距差异性的成因。结果表明:主关键层在破断失稳过程中,弹性能突然释放,形成强烈的震动并释放大量的震动冲击波,震动波传播到采场周围的煤岩体区域引发扰动,从而导致了矿震活动的产生。在结构差异性与载荷和工作面推进速度共同作用下,周期来压步距表现出非均值性。当工作面发生来压时,其能量释放急剧增加,并逐渐趋于平缓,但是能量释放的周期性变化和周期来压又不是完全一致的,存在相对滞后,微震事件数和能量释放量成正比且同样具有滞后现象。主关键层的断裂跨距与上覆岩层性质和厚度有关,软弱层越厚,断裂跨距越小,故在非平原均值的山区,主关键层断裂跨距同样表现出非均值性。
In view of the weak impact tendency at working face 22116, hydraulic support monitoring was used to reveal the influence of main key layer fracture on periodic pressure at the working face, and combined with coupled monitoring of microseismic and electromagnetic radiation, the distribution characteristics of coupling events of microseismic and electromagnetic radiation at the working face were derived, and the cause of the difference in fracture span of main key stratum was analyzed. The results have shown that during failure and instability of the main key layer, elastic energy is suddenly released, forming an intense vibration and releasing a large number of shock waves. The waves are propagated to, coal and rock mass areas around the stope, causing disturbances and subsequent mine seismic activities. Under the combined action of structural difference, load, and advancing speed of working face, periodic pressure step becomes non-mean. When pressure occurs at the working face, its energy release increases sharply and gradually flattens. Still, changes in energy release and periodic pressure are not entirely consistent, and there is a relative lag. The number of microseismic events is proportional to the amount of energy released, and there is also a lag. The fracture span of main key layer is related to the nature and thickness of overlying strata: the thicker the weak layer, the smaller the fracture span. Therefore, the fracture span of main key layer is non-mean in mountainous areas with non-plain mean value.
作者
崔栋歌
朱川曲
李青锋
吴昊
CUI Dongge;ZHU Chuanqu;LI Qingfeng;WU Hao(Hunan Provincial Key Laboratory of Coal Mining Safety Techniques of Coal Mines,Xiangtan,Hunan 41120L China;School of Resources&Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China;Institute of Mineral Engineering,Hunan University of Science and Technology,Xiangtan,Hunan 41120L China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2021年第6期1152-1157,共6页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51474104)
煤矿安全开采技术湖南省重点实验室开放基金项目(E21835)。
关键词
微震
电磁辐射
来压步距
关键层
microseism
electromagnetic radiation
weighting interval
key stratum
