多主梁体系钢板组合梁桥抗力非线性相关性对结构可靠度的影响OA

To provide an insight into the influence of the nonlinear correlation of girder resistances in multi-girder composite I-girder bridges on structural reliability,Copula functions are adopted to model the spatial correlation of several key random variables related to structural resistance.Time-variant correlation among the resistances of different girders is obtained based on these Copula functions,and the effect of these nonlinear relationships on bridge reliability is investigated.The level of spatial correlation among the basic random variables of a specific category related to structural resistances is represented by Kendall's τ correlation coefficient.For the first time,a time-variant analysis of the nonlinear correlation of the structural resistance of composite I-girder bridges with composite sections under corrosion hazards,considering the basic random variables of girder resistances,is conducted.The influence of the nonlinear relationship of girder resistances on the time-variant reliability of multi-girder composite I-girder bridges is also investigated.The results show that the type of Copula function adopted for the correlated basic random variables related to structural resistances has a significant influence on both the correlation of girder resistances and the structural reliability of bridges.This influence is affected by both Kendall's τ correlation coefficient and the system model of the bridge superstructure.