An experimental investigation of ice and snow shedding from bridge cables with and without surface modifications

Ice and snow shedding events on cable-supported bridges around the world have become more frequent in recent years. Although they pose a risk to bridge users and lead to lengthy bridge closures, the research so far has focused mainly on the development of various countermeasures and the aerodynamic behaviour of cables with ice or snow accretions. In this paper, a wind tunnel investigation aimed at simulating atmospheric conditions to reproduce natural accretion and shedding of ice and snow from different bridge cable surfaces is presented. The experimental investigation was carried out at two different climatic wind tunnel facilities and involved the use of two different solar simulators to simulate the effect of solar radiation on the melting and shedding process. It was found that both the colour of the cable surface and the surface modifications had a significant influence on the melting and shedding of ice and snow. Whilst the cable colour affected the heating rate of the cable surface and governed the shedding rate of smooth cable sections, the use of surface modifications such as steel wire mesh was more effective in retaining the accretions for longer and breaking them into smaller pieces. The analysis further revealed how the non-uniform heat transfer distribution around the cables affects the surface temperatures at specific locations and how much solar irradiance is approximately transmitted through the accretions onto the cable surface. These findings improve the fundamental understanding of ice shedding from bridge cables and demonstrate the performance benefits of cable surface modifications in terms of risk mitigation for bridge users.