A discrete element framework for modeling the mechanical behaviour of snow-Part I: Mechanical behaviour and numerical model

A framework for investigating the mechanics of snow is proposed based on an advanced micro-scale approach. Varying strain rates, densities and temperatures are taken into account. Natural hazards i.e. snow avalanches are triggered by snow deforming at low rates, while a large group of industrial applications concerning driving safety or winter sport activities require an understanding of snow behaviour under high deformation rates. On the micro-scale, snow is considered to consist of ice grains joined by ice bonds to build a porous structure. Deformation and failure of bonds and the inter-granular collisions of ice grains determine the macroscopic response under mechanical load. Therefore, this study proposes an inter-granular bond and collision model for snow based on the discrete element method to describe interaction on a grain-scale. It aims at predicting the mechanical behaviour of ice particles under different strain rates using a unified approach. Thus, the proposed algorithm predicts the displacement of each individual grains due to inter-granular forces and torques that derive from bond deformation and grain collision. For this purpose, the inter-granular characteristics are approximated by an elastic viscous-plastic material law which is based on the temperature-dependent properties of poly-crystalline ice Ih.

Automated summary

This study proposes a framework for investigating the mechanics of snow based on advanced micro-scale approach, taking into account varying strain rates, densities, and temperatures. By establishing an inter-granular bond and collision model for snow, the research aims to predict the mechanical behavior of ice particles under different strain rates. This approach involves predicting the displacement of individual grains due to inter-granular forces and torques derived from bond deformation and grain collision, approximated by an elastic viscous-plastic material law based on the temperature-dependent properties of polycrystalline ice Ih.