| Long-span cable-stayed bridge are characterized by their attractive appearance, lower construction cost, and well performance and so on. In recent decades,it has been widely applied because of these advantages, whether domestic or foreign. But with span increases, the problem of the earthquake-resistant capacity is becoming increasingly important. Therefore, it is necessary to research the dynamic property and the earthquake-resistant capacity.Based on a long span cable-stayed birder with twin pylons and four cable planes, using structural analysis program Midas/Civil, a3D finite element model of this bridge is set up, dynamic property calculated, and, the issue of earthquake-resistant capacity is discussed.Firstly, the thesis summarizes the seismic analysis method of long-span bridges. Then, Compared the chinese bridge seismic code with Japanese code,American code and European code respectively, their advantages and disadvantages were pointed out. provides a reference for the perfection of the specification. Next, The bridge analysis model was established with the MIDAS software,based on the method for subspace iteration, the self-vibration period and mode were calculated, the dynamic characteristics analysis was carried out. At last, with the actual response spectrum and the wave, response spectrum analysis and nonlinear time-history analysis were carried out for this cable-stayed bridge, finally, the seismic performance were evaluated according to these analysis results.In this thesis, through analyzing the seismic performance of the cable-stayed bridge, obtained the performance of the cable-stayed bridge under the earthquake, summarized the characteristics of the earthquake response for such bridges, these conclusions render a reference for seismic design of such bridges. |
