Aeroelastic analysis of cable-stayed bridges

The aeroelastic response of cable-stayed bridges to wind is a complex interaction of aerodynamic loading and coupled structural motion. The present paper presents an empirically based analysis method for such structures, based on a flutter-derivative formulation. The principal perceived advantage of the approach adopted herein is that the full three-dimensional complexities of the system may be incorporated, while retaining insight into the physical mechanisms involved. Two examples, covering the erection and completed stages of a twin-deck structure,are presented and discussed. Correlation of the method with three-dimensional wind-tunnel tests is presented. Finally, attention is given to the effects of turbulence in the incoming wind; the flutter-derivative approach is successfully used to explain phenomena observed in full-scale tests and in practice.