Numerical simulation of wind field characteristics at bridge sites in flat and gorge terrains under the moving thunderstorm downburst

To compare the effects of the moving thunderstorm downburst on the wind field characteristics at bridge sites in flat terrain and gorge terrain, numerical simulations were conducted on the wind field characteristics both in the flat and gorge terrains under the moving thunderstorm downburst by using the SST k-ω turbulence model combined with the impinging jet simulation method. Then, the distributions of wind speed and wind attack angle along the bridge girder in these two terrains were compared and analyzed. The results showed that during the motion of the thunderstorm downburst, the wind speeds at the mid-span point of the bridge girder are relatively minimum in flat and gorge terrains, and the farther away from the mid-span point, the greater the wind speed. In the flat terrain, the values of wind attack angle at the monitoring points are mainly negative, while in the gorge terrain, most of the wind attack angles are positive.