Experimental study on fluctuating wind pressure on a long-span dome roof subjected to stationary downburst-like winds

Abstract

Long-span roofs are vulnerable to wind damage, especially from downbursts. Previous studies on downburst-induced wind pressure on these structures have primarily focused on the mean component while neglecting the fluctuating wind pressure. This study aims to analyze the fluctuating wind pressure on a long-span dome roof subjected to stationary downburst-like winds through synchronous wind pressure measurement tests. The experiment considers the impact of the radial distance, which refers to the horizontal distance between the downburst center and the dome roof. A detailed analysis is performed on the distribution condition, correlation coefficient, and coherence of fluctuating wind pressure. The results reveal that the worst fluctuating wind pressure occurs at a radial distance of approximately 1.4 to 1.7 times the downburst jet diameter (D_jet). The strongest correlation of fluctuating wind pressure is observed for measurement points at the windward roof edge, owing to airflow separation. The magnitude of the correlation coefficient generally increases with increasing radial distance from 0.8D_jet to 1.2D_jet, but then decreases with a further increased radial distance. These findings can improve our understanding of downburst-induced fluctuating wind pressure on long-span roofs and provide valuable insights for the downburst-resistant design of relevant engineering structures.