Investigations of water inrushes from aquifers under coal seams
Investigations of water inrushes from aquifers under coal seams
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DOI：
10.1016/j.ijrmms.2004.11.010
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发表时间：
2005-04
影响因子：
7.2
通讯作者：
Jincai Zhang
中科院分区：
文献类型：
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作者：
Jincai Zhang
在许多煤矿中，石灰岩承压含水层位于煤层之下。这些矿井在采煤过程中，突水事故时有发生，后果严重。介绍了煤矿水文地质条件及煤层下含水层可能发生的突水灾害。提出了突水机理。控制矿井突水的主要因素有矿压、开采规模、地质构造和下伏含水层的水压力。分析表明，采动引起的侧限减小是底板岩层导水破坏的主要原因。破坏带的深度与开采宽度密切相关。本文还介绍了底板岩层导水破坏的现场观测结果，并应用有限元法结合应力相关渗透率分析了煤层开采对导水系数的影响。最后，给出了突水预测的理论和经验方法，并提出了改进矿井设计和提高含水层上采煤安全性的技术措施。这些措施包括断层和裂隙灌浆以及采矿方法的改进，如将长壁开采改为短壁开采。
In many coal mines, limestone-confined aquifers underlie coal seams. During coal extraction from these mines, water inrushes occur frequently with disastrous consequences. This paper introduces the hydrogeological conditions of the coal mines and the potential water inrush disasters from aquifers under coal seams. It then presents the water inrush mechanism. The main factors which control water inrushes include strata pressure, mining size, geologic structures and the water pressure in the underlying aquifer. Analysis shows that reduction of confinement due to mining is the major cause of the water-conducting failure in the floor strata. The depth of the failure zone is strongly dependent on the mining width. This paper also presents field observation results of the water-conducting failure in the floor strata, and applies the finite element method coupled with stress-dependent permeability to analyze hydraulic conductivity enhancement due to coal extraction. Finally, theoretical and empirical methods to predict water inrushes are given, and technical measures for improving mine design and safety for coal extraction over aquifers are presented. These measures include fault and fracture grouting and mining method modification such as changing long-wall to short-wall mining.