Estimating the 3-Second Gust on Rooftops of Residential and Low-rise Buildings during a Hurricane
After the passage of a hurricane numerous infrastructures suffer water and wind damages. From engineering meteorology viewpoint, many cases are related to the impact of the wind on a roof. In order to estimate the wind speed on a roof, the three second gust is employed according to ASCE-7 for the wind load analysis. However, since there is no 3-s gust measurement on a roof, constant disputes occur as to who is liable to pay for the damages. After a brief review of recent literature, this technical note provides a methodology to resolve these disputes objectively. The formula is verified by full-scale field measurements during Hurricanes Frances an Ivan. Furthermore, in order to help engineers and contractor estimate the 3-s gust on the rooftop, methods are provided so that the needed 3-s gust can be computed from wind speed measurement available routinely from airports.
