Advanced aerostatic stability analysis of cable-stayed bridges using finite-element method

Based on the concept of limit point instability, an advanced nonlinear finite-element method that can be used to analyze the aerostatic stability of cable-stayed bridges is proposed. Both geometric nonlinearity and three components of wind loads are considered in this method. The example bridge is the second Santou Bay cable-stayed bridge with a main span length of 518 m built in China. Aerostatic stability of the example bridge is investigated using linear and proposed methods. The effect of pitch moment coefficient on the aerostatic stability of the bridge has been studied. The results show that the aerostatic instability analyses of cable-stayed bridges based on the linear method considerably overestimate the wind-resisting capacity of cable-stayed bridges. The proposed method is highly accurate and efficient. Pitch moment coefficient has a major effect on the aerostatic stability of cable-stayed bridges. Finally, the aerostatic failure mechanism of cable-stayed bridges is explained by tracing aerostatic instability path.