Abstract
In this study, to clarify the formation mechanism of snow cornice on the eaves of flat roofs, the relationship between the behavior of snow particles near the eaves and the formation of snow cornice was examined based on wind tunnel tests for flat roofs with parapets. The tests were conducted on using wind tunnel facility owned by Hokkaido University of Science, and a wooden prototype of roof with parapet. The behavior of snow particles was photographed with a high-speed camera, and PTV analysis was performed using these images. In addition, the reproduction test of snow cornice was conducted by continuously suppling natural snow in the wind tunnel. According to the results of PTV analysis, it was clarified that the formation and growth of the snow cornice was due to the movement of snow particles in the wind direction. In the reproduction test of snow cornice, the snowdrift occurred on the eaves of the specimen at wind speed of 3 m/s. Furthermore, the cornice overhanging approximately 0.15m from the eaves was formed. According to the results of analyzing the relationship between the PTV analysis and the cornice reproduction test, the spatial concentration of snow particles increased as the wind speed decreased. The main factor for the formation and growth of the cornice due to snowdrifts on the eaves was that the spatial concentration of snow particles reached saturation.
