Fatigue Evaluation of Flat Steel Box Girders with closed stiffeners of Large-span Suspension Bridges under Different Heavy Trucks

摘要

Due to its outstanding aerodynamic shape and light weight, the trapezoidal cross-section flat steel box girder with orthotropic decks and thin-walled longitudinal stiffeners of trapezoidal section are widely used in long-span suspension bridges in the world. However, because of the geometrical characteristics and the relative flexibility of their components, these structures may be quite susceptible to traffic loadings that fatigue cracks tend to appear in these structures. In this paper, Jiangyin Bridge is used as a case study to investigate the fatigue performance of the steel girders of suspension bridge Jiangyin Bridge is the second longest bridge in China, which has the main span of 1385m. The stress analysis of steel box girders is firstly carried out based on the analysis of fatigue life. Fatigue assessment method is proposed on the basis of in-situ measurement data combined with finite element analysis. A complete fatigue assessment is made in this paper.