Coal Industry Engineering Research Center for Comprehensive Prevention and Control of Mine Water Disaster, School of Earth and Environment, Anhui University of Science and Technology, Huainan, 232001, China.
State Key Laboratory of Water Resource Protection and Utilization in Coal Mining, CHN Energy Shendong Coal Group Co., Ltd, Beijing, China.
Ground Water. 2024 Nov-Dec;62(6):934-944. doi: 10.1111/gwat.13401. Epub 2024 Mar 11.
The safe operation of underground reservoirs and environmental protection heavily rely on the water flow through coal pillar dams in coal mines. Meanwhile, research on the flow characteristics in coal pillar dams has been limited due to their low hydraulic conductivity. To address this gap, this study assembled a novel seepage experimental device and conducted a series of carefully designed seepage experiments to examine the characteristics of low-permeability in coal pillar dams. The experiments aim to explore the relationship between water flux and hydraulic gradient, considering varying core lengths and immersion times. Flow parameters were determined by fitting observed flux-gradient curves with predictions from both Darcy and non-Darcian laws. Several significant results were obtained. First, a noticeable non-linear relationship between water flux and hydraulic gradient was observed, particularly evident at low flow velocities. Second, the non-Darcy laws effectively interpreted the experimental data, with threshold pressure gradients ranging 13.60 to 58.64 for different core lengths. Third, the study established that water immersion significantly affects the flow characteristics of coal pillar dams, resulting in an increased hydraulic conductivity and flow velocity. These findings carry significant implications for the design of coal pillar dams within underground coal mine reservoirs, providing insights for constructing more stable structures and ensuring environmental protection.
地下水库的安全运行和环境保护严重依赖煤矿中煤柱坝的水流。同时，由于其低水力传导率，对煤柱坝中水流特性的研究一直受到限制。为了解决这一差距，本研究组装了一种新型渗流实验装置，并进行了一系列精心设计的渗流实验，以研究煤柱坝中的低渗透性特征。这些实验旨在探讨水通量与水力梯度之间的关系，考虑不同的岩心长度和浸入时间。通过将观察到的通量-梯度曲线与达西和非达西定律的预测进行拟合，确定了流动参数。得到了几个重要的结果。首先，观察到水通量与水力梯度之间存在明显的非线性关系，尤其是在低流速下。其次，非达西定律有效地解释了实验数据，不同岩心长度的门槛压力梯度范围为 13.60 至 58.64。第三，研究表明水浸显著影响煤柱坝的流动特性，导致水力传导率和流速增加。这些发现对地下煤矿水库中煤柱坝的设计具有重要意义，为构建更稳定的结构和确保环境保护提供了见解。
