Three-dimensional Response Characteristics of Self-potential Field for Dam Leakage Hidden Danger

In order to improve the application of self-potential field monitoring in detecting the potential reservoir dam leakage, we deduced the coupling equation of the self-potential field with water flow field and ions diffusion field, based on the formation mechanism of the self-potential field. We realized the three-dimensional numerical simulation of the self-potential field of reservoir dam by coupling finite and infinite elements by analyzing the response characteristics of the self-potential field with different water levels, different levels of danger, and different periods of typical dam leakage models. The results show that the magnitude of the self-potential field is proportional to the size of the leakage channel and the magnitude of water level difference. Thus, the distribution characteristics of the self-potential field could indicate the development period of a leakage to some extent, and the leakage location and early warning could be realized by monitoring self-potential fields.