Study on the Aerodynamic Characteristics of a Single-pylon Cable-stayed Bridge Girder by Numerical Simulation and Wind Tunnel Test

The wind induced vibration is one of the key technical problems for long-span bridge design. Therefore, a study on the aerodynamic characteristics of a single-pylon cable-stayed bridge girder is carried out in this paper. The aerostatic coefficient of the bridge girder, including both construction state and service state, is investigated by wind tunnel test with varying wind attack angle. Then based on the computational fluid dynamics (CFD) method, the flow field around the bridge girder is visualized numerically. The risk of vortex-induced vibration (VIV) is qualitatively evaluated by analyzing the flow features and by considering the Scruton number (Sc). Later a dynamic section model is tested in wind tunnel and the VIV phenomenon is observed subsequently. Results show that the aerodynamic stability is assured by the positive slope of the lift coefficient. The VIV response is influenced by the structural damping and the bridge accessory. The amplitude of VIV response can be lower by increasing the structural damping. The maintenance track rail of the bridge girder also does some good for suppressing the VIV as long as the track rail is located at the appropriate place