Fatigue Behavior Evaluation of Full-Field Hangers in a Rigid Tied Arch High-Speed Railway Bridge: Case Study

Abstract

The steel truss arch is an important structural type for high-speed railway bridges with long spans. The fatigue assessment of rigid hangers under long-term train loads is an important concern. In this study, the Nanjing Dashengguan Bridge, a six-line railway steel arch bridge with three planes of truss arches and the largest span in the world, was taken as a case study. First, a fatigue assessment of one short hanger was carried out based on dynamic strain monitoring data in 215. The influence of bending behavior, train lane, number of carriages, and train speed on the fatigue performance of the short hanger were investigated. Second, the fatigue damage distribution of full-field hangers induced by a single train was analyzed based on a calibrated finite-element model. The influence of driving direction on the fatigue performance of rigid hangers was discussed. Finally, an engineering approach for fatigue performance assessment of full-field hangers was proposed based on annual train volume. Consequently, it was shown that the bending behavior has considerable influence on the fatigue effects of short hangers. In addition, train lane and driving direction also have a significant influence on the fatigue performance of hangers. The fatigue damage of short hangers in the middle truss arch was the most remarkable, followed by the side truss arch on the downstream side (the Beijing–Shanghai High Speed Railway) and then by the side truss arch on the upstream side (the Shanghai–Wuhan–Chengdu Railway), which should be paid greater attention to in daily maintenance.