Landslide onset and dynamics investigated numerically through Particle Finite Element Modelling

Thanks to the development of modern advanced numerical techniques, the modelling of the whole landslide process via a single simulation has become possible today. Even though the capability of these comprehensive numerical techniques in large deformation analysis has been proven with many applications, yet few efforts have been devoted to developing landslide simulation tools addressing both the pre-failure and post-failure analyses. The present thesis focuses on the use of Particle Finite Element Modelling (PFEM) in landslide applications. PFEM was originally proposed for problems of fluid mechanics and has been gradually applied to solid mechanics. The PFEM developed here is based on the optimization solver. To assess its capability, also an additional model has been developed in this thesis work: it is the widely adopted model based on depth-averaged equations (DAEs) solved by a finite difference technique. The DAEs has been validated against analytical and laboratory data as well as against the observations of the 1783 Scilla, Italy, landslide event. The PFEM model has been validated through applications to the slope stability analysis problem and to the run-out analysis of the 2008 Tangjiashan, China, landslide. Further, the PFEM model has been used to capture the slip surface and the deposit profile of the 2013 Cà Mengoni landslide, occurred in northern Apennines, Italy. It is found that the weakening process plays a crucial role in the evolution of landslides. Finally, the onset mechanism and landslide dynamics of soil slopes subjected to seismic loading has been studied via the present approach.