1. School of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China 2. Changjiang Survey, Planning, Design and Research Co., Ltd., Wuhan 430010, China
The internal hidden danger of earth-rock dams is the main cause of dyke accidents, which seriously threatens the safety and stability of the dam. Since the hidden danger of the dam will change with the shape and size over time, it shows obvious electrical structural changes. Therefore, the real-time monitoring of the earth dam can be realized by the time-lapsing resistivity imaging method, so as to achieve the purpose of rapid warning of hidden dangers of the dam and avoid them in time. The damage is caused by hidden dangers. However, the current time-lapsing electric dam hidden danger monitoring technology is mainly based on one-dimensional or two-dimensional medium model, which cannot accurately describe the time-lapse electrical characteristics of three-dimensional dam structure. For this reason, based on high-density DC resistivity detection theory, the authors used the three-dimensional non-structural finite element numerical simulation forward modeling method to simulate the time-lapse variation characteristics of the DC electric field in a typical dam hidden danger model and analyzed the response change law. The results of time-shift monitoring have a good reflection of the trend of hidden dangers of dams. The changes in the size, location and shape of dams can cause regular changes in the amplitude and location of the monitoring. The research results of this paper can provide theoretical guidance for the anomaly identification and disaster warning of time-lapse monitoring of dams.
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