Surrogate model-based flutter reliability analysis of long-span cable-stayed bridges

A reliability analysis method is proposed in this paper through a combination of advantages of the deterministic flutter analysis method considering the effect of additional wind attack angle, Adaptive PC-Kriging model (APCK) and Subset Simulation (SS) method. The proposed method is especially applicable for the flutter reliability evaluation of the long span cable-stayed bridge. After the accuracy and efficiency of the method are demonstrated through four numerical examples, the method is used to estimate the flutter reliability of a cable-stayed bridge. The uncertainties such as material properties, aerodynamic properties and environmental properties are considered. The example cable-stayed bridge is the Sutong Bridge with a main span length of 1088 m built in China. The results show that neglecting the additional wind attack angle will affect results in an overestimation of flutter reliability. The spatial variability and correlation of structural parameters have a significant impact on flutter reliability. Finally, the most influential random variables on flutter reliability of cable-stayed bridges are identified by using a sensitivity analysis.