Abstract: The slope of abandoned waste dump has a weak surface due to the difference in accumula‐ tion layers，and thus there is a risk of landslide damage. Natural factors and human activities around the slope also affect the stability of the slope. To explore the sliding failure mechanism of the dump slope and propose effective control techniques，starting from the engineering geological characteristics of the slope and the mechanical properties of the rock mass，and based on the actual situation of the dump body，the dump slope is divided into four different medium layers from bottom to top. Corresponding mechanical parameters are assigned to different media，and the S1 and S2 calculation sections are constructed in combination with the finite element method. By using the FDEM method，the slope toe excavation calculations of the S1 and S2 sections were carried out respectively in the natural state and the saturated state. Meanwhile，the calcula‐ tion results of slope toe excavation + horizontal vibration of slope toe were compared. By comparing the fail‐ ure modes and displacement monitoring in the simulation results，it is concluded that in the natural state， the excavation at the foot of the slope leads to changes in the contact stress between the media，causing the sliding of the upper soft soil. The vibration caused by the rotation of the concrete mixer promotes the sliding of the soil layer at the foot of the slope. However，as the distance from the vibration source increases，its in‐ fluence relatively weakens. An increase in the saturation of soil mass will enhance the damage degree of landslides. The research proposed treatment measures such as slope reduction and load reduction on the steep vertical surface behind the landslide，filling cracks，and establishing drainage and interception facili‐ ties for the landslide body and the surrounding surface，providing an important reference basis for the stabili‐ ty assessment and risk control of similar waste dump slopes.

Key words: numerical simulation, dump slope, failure mechanism, control technology