Analysis On Dynamic Characteristics Of Semi-Supported CFST Arch Bridge

As a newly-developing bridge style, concrete filled steel tubular (CFST) archbridge has been widely applied and rapidly developed in our country, for its own merits and can make agreement with the factual situation of bridge engineering in China. Because a large number of CFST arch bridge have been or under constructed in our country, the span of arch become larger and the bridge tends to have lighter and thinner structures. So engineers pay more attention to the dynamic behavior of anti-seismic and anti-wind, they also concern the impulse force of vehicle for the CFST arch bridge.By the finite element model (FEM) and testing mode analysis we can obtain the naturalvibration parameters. The natural frequency and mode shape are very important to design andoperation. The thesis will take the example of Phoenix CFST arch bridge, the 3-D finite element model wasbuilt and the natural vibration characteristics was analyzed with the universal FEM software ANSYS. And explained from the type choose, border terms deal with Load respect of dealing with etc. Through the summary of a large number of bridges have been built under different frequency span of the formula for calculating the frequency of fast play an important role in approximation.Use VibSys intelligent analysis of the dynamic signal acquisition system,to the pulse of the main bridge on the experiment, the measuring point arranged in the L / 2, L / 4 and 3L / 4, such as location, measuring a variety of factors outside of the bridge caused by the vibration of small and irregular, microtremor data to spectral analysis, results showed that the bridge structure of natural frequency (fundamental frequency) values measured and calculated values are basically the same, within reasonable limits and that the overall stiffness of the right structure.