VIV mechanism analysis of steel box girder of double continuous girder bridge

Here, vortex induced vibration (VIV) of a double-steel box girder continuous girder bridge was studied by using wind tunnel tests and numerical simulation. Based on the secondary developed user defined function (UDF) program embedded in FLUENT for 2D fluid-structure interaction analysis, VIV of double-box girder bridge section was simulated. By comparing results of bridge segmental model wind tunnel tests and the model numerical simulation results, the reliability of the numerical simulation method was verified, and the VIV mechanism of double-steel box girder section was intuitively analyzed from the perspective of flow field. The results showed that periodic changes of the main vortex on the lower surface of the upstream main beam section and its barotropic zone on the leeward side induce vertical VIV of the upstream main beam section; vortices on upper and lower surfaces of the downstream main beam section alternately act on the main beam section and fall off to form a periodic action, and cause vertical VIV of the downstream main beam section; vortices on upper and lower surfaces of the downstream main beam section are strengthened at windward side railing, upstream box girder tail and front end of downstream box girder, respectively to cause VIV amplitude of the downstream main beam section larger than that of the upstream main beam section; the results provide reference and experience for studying VIV of double-box girder bridges or double-blunt body sections. © 2022, Editorial Office of Journal of Vibration and Shock. All right reserved.