Monitoring of Dry Granular Flows in Unsteady State Down an Inclined Chute

Debris flows are common hazardous events in mountainous areas generally triggered by heavy rainfalls, snow melting or earthquakes. The energy carried by the granular materials that descend steep slopes can put in jeopardy both people and constructions, thus entailing the need to monitor such hazards and to mitigate the risk of these events. Given the natural long runout of these unsteady flow phenomena, it could be interesting to monitor and study their behaviour along transversal cross-sections. To reduce the complexity related to the morphology of the basal surface, the grain size and shape of the flowing material and its water content, this research phase has been carried out with an inclined chute of constant width and with granular materials characterised by high uniformity. A numerical approach based on the Discrete Element Method (DEM) has been considered to have an insight into the experimental observations of the flow characteristics. Clusters of spheres have been used to account for the grains’ shape in the numerical model and the contact parameters have been calibrated against experimental data. Velocity and granular temperature profiles have been considered in order to better understand the behaviour of the flow both along time and space in the monitoring section.