煤层顶板水渗流视电阻率响应实验研究

Experimental Research on Coal Roof Water Seepage Flow Apparent Resistivity Response

通过设计渗流物理模型进行室内实验,用网络并行电法技术采集渗流地电场参数,解编和计算得到视电阻率的动态响应图像,分析认为:煤层开采造成顶板岩层遭到破坏后,上覆水体通过导水裂隙带的渗流可以用视电阻率进行跟踪表达。在相同的时空背景下,随着水量的注入,低阻区的发展呈梯度状蔓延,梯度与水流方向一致。并行电法监测技术获取的视电阻率数据对于渗流场的响应是显著的。3种渗流条件下,视电阻率的变化幅度都已经达到渗流场视电阻率背景值的同一数量等级。视电阻率剖面图中,同时可以反映水的流向和到达位置。利用并行电法技术采集和处理而得到的视电阻率图像可判断煤层开采过程中顶板水情的变化,预测煤矿顶板突水危险,为矿井顶板水害的预警工作提供依据。

Seepage flow models have been designed for laboratory experiment and the parameters of geoelectric field has been acquired using the network parallel electrical method. As a result, the dynamic response of apparent resistivity is obtained by demuhiplexing and calculating. It is found by analysis that, while the roof strata is damaged after coal mining, the seepage of burden water through the fractured zone can be expressed in real-time by apparent resistivity. Under the same space-time background, the spreading of the low resistivity zone is graded; the gradient direction and the water flow are in the same direction. The response of apparent resistivity, acquired by the network parallel electrical method is prominent; and its rangeability can reach the same order of magnitude of the seepage background value in three seepage conditions. Apparent resistivity section can display the direction and position of the stream. In all, apparent resistivity pattern acquired by the network parallel electrical method would be useful to determine the variation of roof water regime in coal mining, to predict the risk of coal mining water inrush, and therefore to provide the basis for mine flood damage early warning.