Studio teorico sperimentale per l'ottimizzazione di barriere flessibili per il contenimento di colate di detrito

The aim of this note is the application of the Rock Engineering System (RES) to design flexible barriers for mitigation against debris flow risk. The study of the interaction between debris flow and flexible barrier is an important challenge because many aspects, related to the basin conditions and the characteristics of the structure, are involved. From the point of view of the phenomenon simulation, this complexity is passed using simplified numerical model. A priori analysis of the different parameters could be useful to correctly define the problem. The application of the RES allows to investigate the triggering criteria, the flow conditions, the depositional process and the interaction with the protection structures, using an interaction matrix that summarizes key parameters. The aim is to quantify the off-diagonal terms in order to assess the residual risk after the barrier construction, considering both back-analysis of real events and data from literature. The intensity evaluation, using the interaction matrix, of the possible pathways allows to identify and evaluate the main parameters that influence the barrier design. This methodology has been applied to analize a real debris flow case occurred in the Italian Western Alps. In particular, to design protection barriers, a numerical analysis has been carried out using a model developed by the Authors (Brighenti et al. 2013). To evaluate the flow characteristics, in terms of velocity and flow height, the numerical code RASH3D (Pirulli, 2010) has been used.