Riccardo Bonomelli

In steep mountain areas, rapid mass movements such as avalanches and debris flows are surface processes which are characterized by large masses of granular material flowing at high speed. These processes may pose a serious threat whenever their path crosses populated areas, or damage key infrastructures like streets or railways. Accordingly, they deserve the highest attention. While multiple mitigation strategies are possible, their choice must be based on suitable physically based models and can’t be done only using historical data, which inevitably are often missing or incomplete. Numerical methods describing the motion of granular material coupled with remote sensing are a viable alternative to properly assess run-off distance, flow velocity, and depositional height.

Modelling impulsive events such as debris flow triggered by excessive rainfall events adopting the Shallow Water Equations with a particular rheological model. Coupling a slope stability and an hydrological model at catchement scale to correctly predict which areas will lose equilibrium and possibly become a debris flow along the drainage network.

Numerical simulations, Finite Volume Methods

The implementation of a Shallow Water Equations 2D solver based on an unstructured grid capable of simulating extreme events in steep mountain areas. The solver encorporates multiple rheological laws to capture the different behaviour and aspect of the debris flow phenomena. A novel slope stability model inside an hydrological model is used to predict the areas which may become unstable during an extreme rainfall event at catchment scale.