Influences Of Vertical Seismic And Nonlinearity On Seismic Response Analysis Of Long-span Cfst Arch Bridge

Increasing continuously along with long-span concrete filled steel tubular arch bridges, it's seismic analysis becomes more important as being a lifeline project. But there is not the regulation about anti-seismic of concrete filled steel tubular arch bridge in code and a little of reference deal with it.In this dissertation, the theories of seismic analysis methods are summarized.In succession, aiming at the Wu Gorge Bridge over Yangtse River, utilizing ANSYS program, established a 3-D finite element calculating models and analyzed the influence of vertical seismic load and nonlinearity for bridges with time-history method. Major research content as follows:1.The natural frequencies are calculated with the subspace iteration method and the properties of free-vibration are analyzed in the part.2.The influene of vertical seismic load on the structure is analyzed with the input of the EL-Centro earthquake wave and Lanzhou earthquake wave.3.The influence of material nonlinearity and geometric nonlinearity on the structure are alse analyzed with the input of the EL-Centro earthquake wave and Lanzhou earthquake wave.The conculations and viewpoints that this article have got can be the reference of seismic designs for long-span concrete filled steel tubular arch bridges, and have some meaning of guidance. But this conculations and regular pattern of this article is drawing out from specific structures and seismic loads, and still needing futher study to prove weather these conculations completely apply to other situations.