Study on the characteristics of self-electric field of adjacent multiple leakage paths embankment dams and dikes under variable water levels

The mastery of the distribution characteristics of the self-electric field of leaking embankment dams and dikes will impose positive effects on both detect and monitor leakage paths by self-potential method. We use numerical simulation and model experiment to investigate the self-electric field of embankment dams and dikes with adjacent multiple leakage paths under fluctuating water levels. The distribution characteristics of self-electric field in embankment dams and dikes with leakage paths at different spatial positions are researched by numerical simulation. The variation of self-potential data of horizontal and vertical survey lines on the surface are analysed. We establish a physical model and confirm that the numerical simulation results are reliable. The results show that as the water-level falls and rises, the self-potential of embankment dams and dikes correspondingly reduces and intensifies. During the water level's descent, a low self-potential region appears above the leakage path's exit, and the magnitude of the self-potential of this region is proportional to the leakage amount. The number and features of the spatial distribution of leakage paths within the dam are understood based on the peak self-potential of the vertical and horizontal survey lines. The findings will further promote the application of self-potential method.