Item: Avalanche pressures at the Vallée de la test site: Interaction of avalanches and narrow structures studied with DEM
-
-
Title: Avalanche pressures at the Vallée de la test site: Interaction of avalanches and narrow structures studied with DEM
Proceedings: International Snow Science Workshop Proceedings 2018, Innsbruck, Austria
Authors:
- Michael Kyburz [ WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland ] [ Environmental Hydraulics Laboratory, Swiss Federal Institute of Technology, Lausanne, Switzerland ]
- Betty Sovilla [ WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland ]
- Johan Gaume [ School of Architecture, Civil and Environmental Engineering, Swiss Federal Institute of Technology, Lausanne, Switzerland ]
- Christophe Ancey [ Environmental Hydraulics Laboratory, Swiss Federal Institute of Technology, Lausanne, Switzerland ]
Date: 2018-10-07
Abstract: Recent advances in full-scale avalanche measurements have led to a better understanding of the avalanche flow dynamics. However, the processes involved in pressure build-up on obstacles in the various flow regimes are still elusive. From full-scale experiments it is well established, that in the inertial flow regime, which is mostly typical of fast and cold avalanches, the pressure is proportional to square velocity. The gravitational regime is often observed for warm/wet snow avalanches and features a linear pressure variation with flow depth. It is still unclear how to estimate the coefficients of proportionality, which are needed for the pressure calculation, namely the drag coefficient and the amplification factor in the inertial regime and in the gravitational regime, respectively. In order to investigate the origin of the amplification factor and the drag coefficient, we developed a model based on the Discrete Element Method (DEM), which allows us to simulate the interaction between a cohesive granular flow, such as an avalanche, and a structure. The DEM model is tested by comparing the simulation results to full-scale measurements from our "Vallée de la Sionne" test site. The results of the simulated pressure show that the newly developed model is able to capture both, the flow-depth and velocity-proportional pressure regime. Thus this model will be further improved to take into account more complex physical processes such as the snow compaction and granulation.
Language of Article: English
Presenters:
Keywords: Avalanche, Pressure, Obstacle, Avalanche dynamics, Discrete Element Method.
Page Number(s): 40-42
-
Digital Abstract Not Available
-