Effects of turbulence on vortex-excited coupled vehicle-bridge systems: Wind tunnel investigation

An accurate assessment of driving comfort and safety of road vehicles on a long-span bridge subjected to vortex-induced vibration (VIV) is crucial for bridge managers to decide whether the bridge should be closed to traffic or not. However, the previous studies often overlook the effects of turbulence on coupled vehicle and bridge systems subjected to VIV although turbulence does exist on site. In this study, vortex-excited coupled truck-bridge deck models were tested in a big wind tunnel under smooth and turbulence flows. Vortex-induced response (VIR) and vortex-induced force (VIF) of the bridge deck and the aerodynamic forces on the truck were measured simultaneously. The effects of the turbulence on VIR and VIF of the bridge deck with the truck(s) placed on different lanes were explored. The effects of turbulence on the mean and peak aerodynamic forces as well as acceleration response of the truck on the vortex-excited bridge deck were also investigated. The results show that VIR and VIF of the bridge deck are significantly influenced by turbulence intensities and truck locations. The mean and peak aerodynamic forces as well as acceleration response of the truck also vary significantly with turbulence intensities and truck locations.