Numerical and experimental study on wind environment at near tower region of a bridge deck

Abstract

The Large Eddy Simulation (LES) turbulence model was used to investigate the wind environment over the deck near bridge tower and was verified using the wind tunnel tests. Compared with the wind tunnel tests, the computational fluid dynamics (CFD) approach was more convenient for the investigations of the local wind field. It was found that the influence of bridge tower on the wind flow can increase rapidly the wind speed on vehicles while bearing off a narrow zone near the tower. The dangerous situation can be effectively compromised by installing a proper local windshield barrier (WSB) with varying heights and porosity ratios along the bridge span. The length of the influence region of tower on the wind environment over the bridge deck was about 7 times of the tower width, implying a proper length of local windshield barriers on each side of the tower. Parametric studies demonstrated that the length of local WSB with different porosity ratios could affect the slope of equivalent wind speeds, indicating that the shorter the length of local WSB was, the rapider the wind speed of the tower influence region varied.