Research About Fatigue Life Of Connection Between Truss Joint And Crossbeam In Steel Bridge

In the last few years, with the development of long span steel truss bridge, angel steel and high-strength bolt are usually adopted to connect the joint of truss joint and cross beam, which have complicate structure and can bear high pressure. The joint fatigue property of truss joint and cross beam plays an important part in bridges safety. Based on Chongqing Chaotianmen Yangtze Bridge, this thesis mainly studied the fatigue properties and life in cross node of truss joint and cross beam. with the method of combination of theory and experiment.First, some basic concepts about steel bridge fatigue, the basic theory for fatigue analysis and main factors influencing the frame fatigue life are illustrated. With the cross node practice of truss joint and cross beam in Chongqing Chaotianmen Yangtze Bridge, the type of joint fatigue belonging to high cycle fatigue is confirmed and the fatigue life is calculated by nominal stress method.Second, the static analysis is carried out by the software of ABAQUS. The structural properties of experiment model is mastered by the static experiment of the model of truss joint and cross beam. The analysis for fatigue life is carried out by the software of MSC.Fatigue based on the ABAQUS finite stress analysis, loading amplitude and the material fatigue property of the experimental model.At last, by comparison between the text result and theory result and according to some related fatigue calculations, the fatigue properties of cross node between truss joint and cross beam of Chongqing Chaotianmen Yangtze Bridge is evaluated.