基于地电场响应的矿井顶板突水模拟实验

建立渗流一电测模型，利用粗砂、中砂、细砂三种含水层介质模拟矿井顶板突水，采用网络并行电法仪实时监测地电场参数的瞬态响应特征。通过分析自然电位、一次场电位、激励电流随时问变化图及视电阻率断面图，发现三种不同含水层介质实验的地电场参数都有明显响应，响应规律基本一致。在突水阶段，粗砂和中砂的自然电位明显低于突水前、后的两个阶段，细砂自然电位持续上升，在突水点有显著变化；一次场电位和激励电流变化一致，与突水前、后的两个阶段相比，一次场电位出现大幅降低，激励电流出现大幅升高；视电阻率断面图可以表征渗流、突水、突水后三个阶段的变化过程，可用于定性判定含水层水量大小。此次研究，对矿井水害的防治研究具有现实意义。

EXPERIMENTAL RESEARCH ON MINE ROOF WATER-INRUSH BASED ON RESPONSE OF GEOELECTRIC FIELD TO GROUNDWATER SEEPAGE

Through the establishment of the model for groundwater seepage-electric test,mine roof water-inrush was simulated and coarse-grained sand,medium-grained sand and fine-grained sand were partly used as aquifer media.The properties of transient response of parameters of the geoelectric field are real time monitored by network parallel electrical equipment.Through analyzing the variation curves of spontaneous potential,exciting voltage and exciting current with time and the pictures of apparent resistivity with time,the authors have found that the experiments on three different kinds of aquifer media show apparent response and basically have the same regularity.In the process of water-inrush,the spontaneous potential of coarse sand and medium sand are significantly lower than that of the two stages before and after water-inrush.The spontaneous potential of fine sand keeps growing and shows significant changes in the water-inrush point.And the exciting voltage and exciting current keep the same changes.Compared with the stages before and after water-inrush,the exciting voltage shows great reduction and the exciting current shows dramatic rise.The apparent resistivity section diagram can clearly show the change process at seepage,water-inrush and post-water-inrush stages,which can be applied to judge the water capacity of aquifer.The study is of practical significance for the study of mine flood forecast and prevention.