Numerical study on landslide dynamic process and its impact damage prediction to brick-concrete buildings, a case from Fenghuang street landslide in Shaanxi, China

Abstract

The study of landslide dynamic process and impact damage has important theoretical and practical significance for landslide risk quantitative assessment. Taking Fenghuang Street landslide in Ningqiang County, Shaanxi Province, China as an example, the dynamic process of landslide and its damage to brick-concrete structure buildings are predicted by using discrete element method. Firstly, a three-dimensional numerical landslide model is established by means of the particle flow code system (PFC3D), which is based on landslide investigation, surveying, engineering exploration and geotechnical testing. Secondly, the whole process of landslide deformation, failure, movement and impact damage was simulated, and the velocity, displacement and impact force of the landslide in the motion process were quantitatively studied. Thirdly, the building model (brick-concrete structure) located at the foot of the landslide was constructed by PFC3D and finite element software (Midas/gen), respectively. The characteristics of deformation and displacement of the buildings after the landslide impact are analyzed, and the impact damage of the landslide is predicted. The results show that the rear edge of Fenghuang Street landslide first deforms and fails, and the leading edge is gradually pushed out. After the locking section of the front edge is broken, the landslide begins to slide as a whole, which is a typical push landslide. The main sliding time of the landslide is about 30 s, the maximum average velocity is 3.2 m/s, and the maximum displacement is about 40 m. After the landslide hits the building, the building is displaced in the moving direction of the landslide, and the wall of the building impacted by the landslide is destroyed, resulting in an collapse evident. The relevant research methodologies and findings in this paper can provide a reference for the risk assessment of the same type of landslides, especially the quantitative assessment of the vulnerability for the brick-concrete buildings at risk.