Estimation of directional design wind speeds via multiple population genetic algorithm

Abstract

The implementation of the probability analysis method on extreme wind loads considering the directionality and uncertainties of the wind load effect coefficients and wind speeds can yield accurate design wind loads. However, it is difficult to popularize this method among structural designers because its theory and calculation process are complicated. The directional design wind speeds for a given city, which are more suitable in the commonly used simplified method for estimating the wind loads (i.e., the sector-by-sector method), are obtained in this study via multi-parameter optimization. A multiple population genetic algorithm program is established for optimization based on the time histories of the wind pressure coefficients obtained from numerous wind pressure taps of different rigid models. For different structural aerodynamic characteristics, the proposed directional design wind speeds can be combined with the sector-by-sector method to obtain results that are closest to the overall reference values of the design wind pressures of all pressure taps under a certain safety guarantee. The applicability, economy, and safety of the sector-by-sector method with the proposed directional design wind speeds are discussed in comparison to other simplified estimation methods using examples of Des Moines, IA, USA, and Shanghai, China, for non-typhoon and typhoon-prone climates, respectively.