Wind and Structures

Volume 41, Number 6, 2025, pages 481-494

DOI: 10.12989/was.2025.41.6.481

Vortex-induced vibrations of a bridge in non-stationary and non-uniform wind fields

XiaoLong Deng , Hao Hong , Pengfei Lin , Gang Hu , Wenli Chen , Bernd R. Noack

Abstract

This study experimentally investigates the vortex-induced vibration (VIV) of a 1:50 scale box girder bridge model in a multi-fan wind tunnel. We generated complex wind fields to reflect realistic conditions, including non-stationary (linearly increasing/decreasing, sinusoidal, and random) and spanwise non-uniform (linear and parabolic) velocity profiles. The effect of turbulence was also examined using active control blades at the tunnel inlet. Results show that all non-stationary and non uniform conditions reduce VIV displacement compared to stationary and uniform flow. Notably, a parabolic wind profile reduced the VIV RMS displacement by 34.4%, proving more effective in suppressing the VIV amplitude than a linear profile (7.8% reduction) due to its greater disruption of spanwise vortex correlation. In the non-stationary flow, the VIV response is governed by the time available for energy accumulation. Furthermore, a significant asymmetry was observed, with gradually increasing wind velocities inducing substantially larger VIV amplitudes than decreasing velocities, suggesting a hysteresis effect. For the random wind fields, VIV was significant when the velocity range (Max-Min=1 m/s) was close to the stationary VIV range (Max-Min=0.8 m/s), but became negligible when the range was larger (Max-Min=2 m/s). Activating the blades intensified turbulence (e.g., from 4.0% to 14.7%), which consistently suppressed VIV by disrupting periodic vortex shedding. These findings underscore the importance of considering spatio-temporal wind variations in bridge aerodynamics, as traditional uniform flow tests may be overly conservative.

Key Words

long-span bridge; multi-fan wind tunnel; non-stationary wind field; non-uniform wind field; vortex-induced vibration

Address

PDF Viewer

Preview is limited to the first 3 pages. Sign in to access the full PDF.

Loading…