Research on deformation and stability of reservoir bank slopes is one of the focus in the world. Taking a deposit slope in the hydropower reservoir area for example

the deformation and failure characteristics of the slope are predicted by FLAC3D while the reservoir level is rising and rapid drawdown. It is indicated that deformation mainly occurred in the deposit body while the reservoir level fluctuating; the deposit body is divided into three regions according to the deformation characteristics: the front traction deformation area with the largest deformation

the middle transition area with the smallest deformation and the posterior passive traction deformation area. Displacement monitoring points are set at different places of the slope body; so the displacement-time graphs during reservoir filling and rapid drawdown of reservoir level are obtained. The monitoring results show that the local instability occurred at the front of the slope during the rapid drawdown of the reservoir level. Owing to the influence of water two potential sliding failure surfaces in slope can be judged based on the shear strain increment.