One-dimensional simulation of debris-flow inception and propagation

The paper describes the development and the assessment of a numerical model for the simulation of debris flow phenomena. Aiming at this, after having considered the causes of triggering, this work focuses on the simulation of propagation characteristics of the masses mobilized, taking into account both the actual internal dissipative processes characterizing the sediment-water mixture and the effects induced by the modification of the boundaries where the flow takes place. The propagation model implemented is based on the one-dimensional hyperconcentrated shallow flows equations, suitable to take into account also the solid and fluid mass exchanges with the bottom. This system of non-linear partial differential equations is integrated by means of a one-dimensional finite volume scheme, second-order accurate in space and time. In order to show the performance and capabilities of the model, the results of its application to a laboratory dam-break experiment are analysed, and finally the application to a real-world test-case is discussed