Snowshed Location And Design

The location and design of snowsheds for avalanche defense must be based on careful studies of terrain, the frequency of avalanche occurrence, and the size of the avalanche. Preliminary observation at sites of planned avalanche defense work is outlined. Factors that must be taken into consideration in the structural design of snowsheds are: Loads by moving avalanches and by deposited snow, length of the shed, lighting, drainage, and maintenance. The length of sheds can be reduced by dams and walls built parallel to the direction of the avalanches. These factors are described with reference to the design and performance of the snowsheds for the Trans-Canada Highway at Rogers Pass, British Columbia. Long, continuous snowsheds covering more than one avalanche track were found to be more advantageous than a number of short sheds with short, open spaces between.