Dynamic Characteristics And Responses Of Concrete-filled Steel Tube Arch Bridges

Concrete-filled steel tube arch bridges have developed rapidly in China in the last twenty years, and China has been at the cutting-edge of the application of this type of bridge. However, the study on concrete-filled steel arch bridges gets relatively behind the engineering practice, and is far from a mature design theory, especially on the research on dynamic characteristics.On the basis of sufficient literature review, the author made a detailed introduction and summary of the related former works achieved abroad and home. The efficiency of seven different objective functions based on dynamic behavior, such as frequency, mode shape, mode shape curvature, modal flexibility, static displacement shape, static displacement shape curvature and static displacement residual, were compared by the use of a numerical model of a simple support beam.Based on a real concrete-filled steel tube arch bridge, this research consisted of establishing the finite element model with software ANSYS and analytical work of dynamic characteristics. The relationship between the effects on the dynamic characteristics and structural parameter changes was developed, and finite element model updating was conducted. The dynamic characteristics of the updated model by frequency function combined with static displacements agreed well with those from dynamic test.The vehicle-bridge interaction was investigated using the updated finite element model, by which the effects on dynamic responses of the bridge of vehicle damping, velocity and weight were briefly analyzed.