Risk analysis of building damage induced by landslide impact disaster

Assessing building damage in a geological landslide is a dynamic process in which the event can be regarded as the combined effect of the landslide impact and the building's response. In conventional models, a landslide mass is typically assumed to be rigid, and standard energy principles are used to calculate equivalent impact loads. Because the disintegration phenomenon of a landslide mass is being ignored, the conventional method often leads to a larger impact force than observed in reality. Based on a case study of a critical landslide, this paper applies a granular discrete element method to investigate landslide processes. First, macroscopic and meso-structural parameters are calibrated through biaxial simulation tests. Second, energy conversion laws between the impact force, geotechnical strength parameters and the outrun distance of the landslide are studied, providing a more realistic load curve of the landslide impact. Finally, a distressed building model is established through a loading curve analysis to study the structural damage state with different parameters. Numerical results show that building damage can be characterised through an equivalent impact force and that the precise calculation of dissipated energy in a landslide is greatly improved by taking into account both the energy dissipation at the slipping surface and the internal friction in the rock mass. The proposed evaluation factor of the damage degree of buildings shows great promise in analysing landslide motion and assessing the safety of building structures.