Simulation studies for the detection of water-bearing structures based on the mine-induced polarization method

Accurately predicting the water-bearing structure ahead of the mining face is an urgent problem to be solved in the field of water prevention and control in coal mines. Based on the sensitivity of the polarizability and quadratic time difference parameters to the response of the water body, the induced polarization method is introduced into the advanced detection of the coal mining face. The finite element numerical simulation was used to create forward model of the apparent polarizability response of a typical water-bearing fault structure. It shows that the curve of apparent polarizability varies with the distance from the water-bearing fault to the tunnel face, which appears the law of increasing first and then decreasing, and the maximum point corresponds to the location of the water-bearing fault. The relationship between the half-decay time and the supply current was studied by physical simulation. It shows that half-decay time decreases first and then increases as the current increases under water-bearing conditions. The model has the highest positive slope at half-decay time from 50 to 150 mA, which provides the possibility for the application of coal mine explosion-proof instruments. The positive value of the quadratic time difference and the envelope area between the zero axes is coherent with the amount of water. The results show that it is feasible to predict the water-bearing structure and its relative water volume by advanced detection of mine-induced polarization method under full space conditions.