Abstract: In view of the mine water inrush warning requirements, based on three kinds of laboratory experiments and one field test in coal mine, the dynamic response characteristics of primary voltage U to groundwater seepage was studied. During the field test, the primary voltage U and the water yield Qo in water inrush process were detected. Physical simulation experiments of steady seepage in both homogeneous and heterogeneous media have indicated that before water-saturated of solid /water two-phase medium, the variation of primary voltage U contains two stages: there exists a second-order relations between the variables of U and Qi in the first stage, while U tends to be stable, and is no longer varying with the increase of Qi in the second one. Additionally, seepage experiments under mining conditions have indicated that the seepage evolution affected by mining can be regarded as the continuation of many small steady seepage processes, and the relation between U and Qi accords with steady seepage characteristics in each small steady seepage process. Moreover, field test shows that there exits a negative correlation between U and Qo in the detection area during roof water inrush process.

Key words: ground water seepage, mining, primary electric voltage, quantitative study, water disaster early-warning