Abstract
The static and dynamic wind-induced instability analyses of super long-span cable-stayed bridges with main span length of 1200～1800m are presented in this paper. Firstly, the static aeroelastic behaviors of bridges against displacement-dependent wind load are investigated by three-dimension geometrical nonlinear analysis. Secondly, the free vibration and flutter analyses are carried out. The comparisons of structural dynamic properties between cable-stayed and suspension bridges are discussed and the impact of the cable vibration effect on the dynamic characteristics and the flutter behavior is studied. The analytical results show that static instability controls the dimension of the girder and the safety against both static and dynamic instabilities can be ensured even with main span length of 1800m.
