Aerodynamic force correlation of a foundational streamlined box girder under vortex-induced vibration in turbulent flow fields

Study on the vortex-induced vibration (VIV) performance of structures under vibration states in turbulent flow fields is closer to the essence of bridge VIV in real service environments, which has been lacking in existing research. The key parameter used in the VIV performance evaluation, vortex-induced force (VIF) correlation, was focused on in this paper. A foundational streamlined box girder was selected, and free vibration sectional model tests were conducted in turbulent flow fields using synchronous pressure-vibration measurement. The results indicate that turbulence have an impact on the VIV performance of streamlined box girder. The presence of turbulence is likely to decrease the VIV amplitude, but sometimes it may also increase it. The phase difference between the leading and trailing edges of the structural upper surface is approximately 100°, and the vortices on the upper surface do not drift continuously. The streamwise correlation of VIFs decreases to varying degrees with the increase in turbulence intensity. The aerodynamic force spanwise correlation when the structure is stationary is significantly weaker than when it is in a vibrational state. When the structure experiences sustained VIV, the spanwise correlation of VIFs decreases with increasing turbulence intensity, increases with increasing amplitude, and decreases with increasing spanwise distance and tends to be constant at a certain distance. Finally, an extended model based on Ricciardelli's correlation function was proposed, which can better describe the VIF spanwise correlation of streamlined box girders under different amplitudes.