Abstract: The seepage field change and slope instability induced by the fluctuation of the reservoir pool levels are presented in this paper. The engineering geologic conditions of Tangjiawan Eastern Slope are discussed based on the geotechnical engineering investigation data. The seepage fields under the pool level fluctuations are numerically simulated by using GeoSlope software. The slope stability of the Eastern Slope under the pool level fluctuation is analyzed by considering the matric suction in the soil mass and its effect on the residual thrust force in the analysis. The mitigation measures are proposed accordingly. The construction monitoring data indicate that this proposed mitigation method is effectively controlled the deformation of the reservoir slope.

Key words: Reservoir Slopes, Pool Level Fluctuations, Seepage Simulation, Stability Analysis, Mitigation and Monitoring