Snow Pressure on Rigid Obstacles

Abstract

In this paper a continuum mechanical formulation of snow pressure is given. The snow pressure against retaining structures on slopes is considered in two separate parts: (1) the static component due to the regression of transverse expansion as discussed by Haefeli, and (2) the dynamic component due to the interruption of the creep (internal deformation) and glide (slip of the entire snow cover over the ground). Snow-pressure calculations made using the non-linear viscous constitutive equations given by McClung (in press) are given for the plane strain-rate problem of a rigid barrier on a snow-covered slope. These calculations are compared with the previous formulation of snow pressure given by Haefeli for the expected range of boundary conditions for the structure and for the snow-earth interface. The results show that the original formulation by Haefeli gives a dynamic component of similar magnitude to the present calculations. Substantial differences are apparent when the up-slope distances for interruption of the creep and glide processes are compared.