Abstract

The paper is to detect the leakage inlets, determine the leakage pathways through the dam, and ensure that the amount of the leakage in the upstream and downstream is consistent, and that there is no leakage around the concrete face rockfill dam. The injection of a pseudo-random current in the water between two aluminum sheets A and B generates a current field that can be measured in the water with sensitive current sensors. When the current is channeled along leakage pathways, the flow-field fitting method can be used to detect these inlets of the leakage pathways. We first review the background equations for the seepage field and the current field in the flow-field fitting method, and we also use an approach to calculate the discharge and ensure the consistency of the upstream and downstream leakage based on the Doppler effect in physics. Moreover, to illustrate how the flow-field fitting method works, we use numerical simulation method to verify the feasibility of the flow-field fitting method. Lastly, we proceed with a case study for which the flow-field fitting method and the acoustic Doppler flow velocity measurement are used to identify and map potential leakage pathways bypassing upstream into the flow measurement weir of the downstream. The approaches proposed in this paper successfully detect three leakage areas and obtain the discharge. The results of detected in a case study provide engineering geology information for optimizing the layout of grouting holes.