A review of critical scouring velocity of compact roof aggregate

This paper provides a review of previous studies on how various building parameters affect the critical scouring velocity of roof aggregate, and how these data can be used from a risk mitigation point of view. The review suggests that the data are available only up to a building height of 45 m, with and without parapets, and with no roof-mounted equipment. However, loosely-laid roof aggregate is currently used up to an approximate building height of 150 m in some cities, and these buildings usually have substantial roof-mounted equipment and parapets that are typically less than 1.8 m high. The available data may not necessarily provide reliable recommendations when extrapolated to these high-rise buildings as the aerodynamics of low-rise to high-rise buildings are different and can be influenced by the presence of roof-mounted equipment. The paper concludes by suggesting confidence limits when extrapolating existing data and identifying areas that need further research to address the critical scouring velocity of loosely-laid roof aggregate for low-rise and high-rise buildings.