Research on the Dynamic Characteristics and Disaster Mechanism of Anti-Slide Short Pile-Supported Slopes

The terrain in Southwest China is predominantly mountainous, with many slopes requiring reinforcement. In addition, this region experiences frequent rainfall and earthquakes that can easily trigger landslides. Therefore, studies on slope reinforcement are crucial. This paper presents a case study of a slope stabilisation project along the Yunyang–Fengjie Expressway in Chongqing, focusing on the seismic performance of anti-slide short pile-supported slopes. The failure evolution process of an anti-slide short pile-supported slope is obtained by inputting a Wenchuan earthquake wave and continuously increasing the amplitude of the seismic wave. The experimental results indicate that the failure mode of the slope consists of tensile and shear components with tensile cracks at the crest and shear cracks in the remaining fractured sections. The anti-slide short piles effectively alter the downward extension direction of the shear cracks. As the shear crack approaches the station of the anti-slide piles, its development path along the weak structural plane changes, extending towards the top of the anti-slide piles and ultimately leading to cap failure. The bending moment of the anti-slide piles under seismic action primarily follow a parabolic shape, with the maximum value located near the weak structural plane.