Mechanical analysis of the seasonal snow cover

A snow model has been developed to calculate the forces and displacements of a seasonal snow cover in order to obtain information on damage caused by snow to forestry plants and technological constructions. Two components of motion may be observed in a settled snowpack: creeping (internal deformation), depending on the internal body weight, and gliding (slip of the entire snowpack over the ground), this is caused by external factors such as free water in the boundary layer or a lack of macroscopic roughness. This model is based on the simplification that the snow cover is an isotropic and homogenous material. For this application the slope is divided into quadrangular finite elements and the creeping behaviour is assigned to them. Depending on the period of model usage it was chosen between two material models: a linear viscoelastic model of snow for a shorter period of consideration and a linear viscous model of material for a longer period of consideration. Gliding is described by verifying the parameter of friction and by geometrical means of description whereby the macroscopic ground roughness is assumed to be modelled by a simple sine wave. (C) 2000 Elsevier Science Ltd. All rights reserved.