This paper was presented at the "Geometric design and safety" session. These proceedings are available on CD-ROM. The Ministere des Transports du Quebec has implemented an experimental research project to examine the effect of snow build-up on the efficiency of a parapet. Although it is well known that a build-up of snow or ice against a barrier can make it easier for an errant vehicle to career over it, there is limited understanding of this behaviour. The project's primary goal, based on the Ministere's safety objectives, is to assess the risk of a vehicle overturning or jumping the barrier in snow conditions, in order to optimize operations and reassess certain design criteria of parapets for winter conditions. Based on the results obtained, a scale of degree of risk was established which factored in the charateristics of the snow build-up and the parapet. Using this scale, we formulated recommendations regarding the criteria of parapet design and the possibility of modifying existing structures. However, the results did not allow definition of a threshold level for snow removal that was completely free of risk. However, using the scale of degree of risk will optimize the planning of snow removal operations to ensure highway safety. (A)
Abstract