Study on the Mechanism of Landslide Steering Deformation under Complex Moving Path

The landslide is affected by the topography and sliding surface morphology. In the process of movement, it often shows complex behaviors such as steering, bifurcation and aggregation. It is of great significance to study the mechanism of landslide steering deformation under complex moving paths for prevention and mitigation of landslide disaster. Based on the three-dimensional geological modeling technology, the three-dimensional particle flow model of Pangjiawan landslide is constructed. Through PFC simulation of landslide movement process, following conclusions are conducted: Steering and aggregation occurred in the Pangjiawan landslide, and the sliding direction of the soil in the middle and back of the landslide deflected and the soil aggregates with that from the northeast region at slope toe; The particles with turning movement in the middle of the landslide begin to slide first with fast speed, and the speed decreases radially from the middle of the landslide to the surrounding area. The leading edge of the landslide keeps a high speed during the whole movement, while the trailing edge of the landslide moves slowly. In addition, the surface velocity of the landslide is larger than that of the interior and bottom of the landslide, and the different velocity of each part of the landslide is an important reason for the steering deformation of the landslide. It reveals the movement law and steering deformation mechanism of complex moving landslides, and provides a theoretical basis for evaluating landslide risks and adopting more reasonable prevention schemes.