Rheology of hail-debris flow and implications in flow mobility

During 29-31 January 2021 (austral summer), an extreme storm event triggered catastrophic debris flows in central Chile (33-36°S). At small and precarious rural settlements the commune of Malloa Chile, where by a hailstorm. Hail-debris flows, with hail volume concentration near 10%-20%, caused 200 injured individuals 73 damaged houses. In this study, hail-debris modelled using FLO2D. software, calibrated against flow velocities flooded areas obtained from audio-visual records taken local inhabitants (using cell phones) high-accuracy post-event topography drone. Results suggest that content significantly reduces resistance compared to typical thus increasing velocity, run out. On other hand, damage infrastructure was more related materiality houses (precarious settlements) than severity.