湖下采煤下渗模型试验与规律研究

Model tests on seepage and rules of coal mining under water

根据地质力学模型试验原理和南四湖的工程地质与水文地质条件,建立了12个地质模型。通过模拟湖下煤层的开采过程,分析了煤层上部的砂岩和灰岩的破坏特征及地面开采盆地的形成过程。通过测量上层滞水位和潜水位随开采的变化和水位的恢复过程分析了湖下采煤对南四湖湖水的影响和湖水下渗的规律。研究发现:如果湖下存在2~3 m左右的黏土层,地表湖水基本上不会渗透到地下,也不会造成地表水的大量损失。开采时潜水位会随着开采产生周期性下降,停采后周围潜水会侧向补给采空区,潜水位逐渐恢复,在南四湖的地质条件下,潜水位恢复到原来的95%,大约需要一年的时间。

Based on the test principles of geological mechanics model and engineering geological and hydrogeological conditions of Nansi Lake, 12 geological mechanics model are established. By simulating the coal mining under the lake, the failure process of sandstone and limestone above the coal and the formation process of ground mining basin are studied. By measuring the change of perched water level and groundwater level with coal mining under the lake, the water level of the lake is studied. The seepage process from the lake to the mining pit is also studied. If there is a clay layer with depth of 2 to 3 m, the amount of leakage will be very small. The water in the lake will not be affected. The perched water level will cyclically decline with coal mining. But when the coal mining stops, the perched water level will gradually recover. For the restoration of the perched water level to its original 95%, it needs about 1 year under the engineering geological and hydrogeological conditions of Nansi Lake.