Wind-induced Response Analysis Of Long-span Concrete-filled Steel Tube Arch Bridge

With the development of science and technology, the span of bridge tends to be increasing and that wind-resistant problems have become a key problem in the design of long span bridge. Though the concrete-filled steel tube arch bridge has been widely applied in recent years, the researches of its static and dynamic analysis in structure wind resistance aspect are not yet perfect. Based on the background of the Wu Gorge Bridge of Yangtze River which is a semi-supported concrete-filled steel tube arch bridge with a main span of 460m, this dissertation is concentrated on the static gust responses, especially on the wind-induced buffeting responses. The main tasks are as follows:1. According to the feature of the wind speed spectrum for the long-span steel tube arch bridge varied with the height, the stochastic wind field on the site was simulated using the harmony superposition method.2. The finite element model of Wu Gorge of Yangtze River Bridge was established by means of the finite element analysis software ANSYS and its dynamic characteristics were analyzed at the same time.3. Based on the static gust theory, the static gust responses of the concrete-filled steel tube arch bridge were analyzed.The effects of structural geometric nonlinearity to the static gust responses were mainly studied.4. Based on the time domain wind loads obtained by wind field simulation, the linear and nonlinear time domain buffeting response were analyzed for the bridge by means of ANSYS software. In order to get the stable results, the nonlinear motion equation was solved by the combination of Newmark ?βmethod and the Newton? Raphson iterative method.Some useful conclusions were given through the research, the wind-resistance research of the long-span concrete-filled steel tube arch bridges were further improved and valuable reference was provided for the wind-resistant design of similar bridges.