Impact Forces and Energy of Flow-like Landslides Against Protection Barriers: a New MPM-validated Empirical Formulation

Abstract Full understanding the interaction mechanisms between flow-like landslides and the impacted protection structures is an open issue. In fact, while researchers have used several approaches, from experimental to numerical, it is true that the adequate assessment of the hydromechanical behaviour of the landslide body requires both a multiphase and large deformation approach.This paper firstly proposes a conceptual framework for a specific type of protection structure, namely a rigid barrier fixed to the base ground. Two different approaches are proposed: i) an advanced hydro-mechanical numerical model based on Material Point Method is tested in simulating the whole complex landslide-structure-interaction mechanism(s), ii) a more simplified empirical model is casted to estimate the impact force and the time evolution of kinetic energy. The calibration and validation of the empirical formulation are pursued, respectively, based on the MPM numerical results, and referring to a large dataset of field evidence for the peak impact pressure. Finally, the performance of the newly proposed empirical method is compared to the methods available in the literature and its advantages are outlined.