A numerical model for the simulation of debris flow triggering, propagation and arrest

Abstract

In this paper, it is described the development and the assessment of a 1D numerical procedure for the simulation of debris flow phenomena. The procedure focuses on: (1) the rainfall triggering, and the effects induced on slope stability by both rainfall infiltration and groundwater dynamics; (2) the possible inception of debris flows during the propagation phenomenon itself, due to the actions exerted on the slope by the already triggered flowing masses; (3) the propagation phenomenon over complex topographies; (4) the non-Newtonian internal dissipative processes that develop within the sediment–water mixture; (5) the effects induced by the evolution of the boundaries where the propagation phenomenon occurs; (6) the run-out and arrest phenomena. In order to show the performance and capabilities of the model, the results of its application to an analytic test and to laboratory experimental tests are first analyzed, and finally, the application to a plausible debris flow scenario, taken from a real case study, is discussed.