Abstract: During the construction of pumped storage power stations, numerous large soil and rock slopes have been formed, and their stability seriously affect the reliable operation of the projects. We use a three-dimensional discrete element simulation method to study the instability process and impact range of the slopes, reflecting more accurately the characteristics of soil and stone materials and the large deformation characteristics of slope instability and the anti-sliding effect of baffles. Based on the accumulation forms and velocity variation patterns of sliding bodies, the instability of soil and rock slopes is divided into four stages: rapid sliding, secondary sliding, stable sliding, and creep sliding. By monitoring the velocity and energy evolution of particles at different positions, the impact of slope instability without protective measures on the downstream rivers and buildings is analyzed. By developing discrete element simulation schemes for rectangular, circular, and triangular cross-sections of the array baffles, an evaluation system for their anti-sliding effect is constructed, including multiple evaluation indicators such as impact force, stacking velocity, stacking displacement, and their interception capacity. After comprehensive analysis, we recommend that triangular cross-section array baffles be adopted for the soil and rock slope engineering of the Zhen'an pumped storage power station. This study is thought to be useful for instability simulation and protection design of similar slope engineering.

Key words: pumped storage power station, soil-rock mixture, discrete element method, impact, array baffle