MPM-modelling of Reinforced-Concrete walls as protection structures against flow-like landslides

The use of massive protection structures against flow-like landslides, such as Reinforced Concrete (RC) walls, has been tested especially for rockfalls and to reduce the kinetic energy of boulders. In some contexts of debris flows, similar mitigation strategies have been pursued through cluster of blocks or baffles, especially in Asia. But it is still challenging: 1) the assessment of hydro-mechanical behavior of the landslide body, which is a mixture of solid skeleton saturated with water, during the impact; 2) to consider that protection works are always somehow deformable. Thus, both a multiphase approach and a large deformation formulation are fundamental to properly simulate the kinematics of the flowing material during the impact. This paper provides a contribution using the Material Point Method (MPM) numerical approach to the case of landslide of flow type impacting different types of protection structures, made of steel-reinforced concrete elements. The landslide is assumed with a non-zero initial velocity, and saturated. The landslide motion, the interaction with the structure and the base soil, and the final landslide deposition are simulated for a range of scenarios.