Study on Suspender’s Fatigue Performance of Half-through CFST Arch Bridge due to Vehicular Loads

Due to the repeated action of vehicular loads, fatigue failure of suspenders of half-through arch bridge is main failure type. Usually the stress history of suspender is relevant with the vehicle load, dynamic property of structure and so on. In this paper, the traffic load spectrum investigation of Ha-Tong road is constructed through a 24-hour traffic flow investigation; And the space FEM established to get the stress response；Assume the fatigue performance of suspender as stochastic variable, the stress history of suspender is a stochastic process which changes with time, fatigue reliability analysis model is suggested based on accumulated damage model；Taking YIlan bridge as an example, the study on the effect of suspenders’ length and deck type are carried out. The research method and results can be referenced while designing or evaluating the same bridge type.