Date of Award
Ph.D. in Engineering Science
Large scale events such as landslides, debris-flows, and industrial accidents like tailings dams failures are hard to predict, highly dangerous, and destructive. This research work aims to study similar granular flows with controlled laboratory experiments and numerical simulations. Monodisperse and well-graded granular materials were instantaneously released in a rectangular channel with varying degrees of initial saturation. Non-intrusive laboratory measurement techniques were developed to collect data from experiments at a high spatial and temporal resolution, including flow interfaces and velocity fields. The measured data were used to estimate constitutive model parameters. Experimental results show that the selection of the constitutive relationship depends on the initial flow conditions. Using the Material Point Method (MPM), it was shown that a simple Mohr-Coulomb model could reasonably represent the dry granular dam-break flows, but that a custom Mohr-Coulomb model taking strain softening into account was necessary to capture more complex flow features such as progressive and block failures that occurred during the experiments when the granular matrix was initially saturated. The calibration of such models is challenging as multiple factors come into play at the same time. The use of such models to simulate real life large scale events is still in its infancy and must be done carefully and be data driven. These challenges are laid out in this research study.
Rébillout, Luc Remi, "Experimental investigation of granular dam-break flows and their rheological properties" (2021). Electronic Theses and Dissertations. 2170.