Analysis On Dynamic Characteristics Of Semi-Supported ArchBridges

The main aspects of concrete-filled steel tube (CFST) arch bridge dynamic specifications study are natural vibration parameters and dynamic response analysis. CFST arch bridges have long span, light weight and low stiffness. At the same time the dynamic specifications of CFST are very complication, the natural vibration frequencies in plane are higher. The CFST arch bridges are flexible structure;it is necessary to deal with the long-span CFST arch bridges.By the finite element model (FEM) and testing mode analysis we can obtain the natural vibration parameters. The natural frequency and mode shape are very important to design and operation. The thesis will analyze the CFST semi-supported arch bridge and pose the range and formulation of the base frequency of the CFST semi-supported arch bridges.The compulsive vibrations of bridge include: vehicles load impaction, wind dynamic impaction and the earthquake impaction. While the most damage and destroy is attribute to the vehicles load recapitulate impaction. So, the compulsive vibration response analysis of bridge by the vehicles load is very important. By the dynamic test, we can imitate the various situations to obtain the exact dynamic response parameters of bridge, sum up the damping ratio and frequency curve of semi-supported CFST arch bridge and the formulation of the impact coefficient.