Analysis Of Seismic Response Of Long-Span PC Cable-stayed Bridge

Cable-stayed bridge is a kind of bridge whose main girder is directly pulled on the bridge tower with many cables.Cable-stayed bridge,as a kind of cable system,has more crossing capacity than girder bridge,and is the main type of long-span bridge.The first modern cable-stayed bridge was the 182.6m Stromsund bridge,built in Sweden by Germany's DEMAG in 1955.The largest span cable-stayed bridge in the world is the Russky Island Bridge in Russia.The main span is 1104 meters,which was completed in July 2012.As is known to all,China is an earthquake-prone country,only after the Sichuan Wenchuan earthquake,China has happened Qinghai Yushu earthquake,Sichuan Ya'an earthquake and so on,everytime the earthquake has brought immeasurable losses of people's lives and property.Indeed,the cable-stayed bridge is widely used as the traffic control node,if once being destroyed,it would not only directly cause huge losses but also increase the difficulty of disaster relief and increase the rate of secondary disasters.To some extent,it's of great significance to fully understand the seismic performance of the long-span PC cable-stayed bridge to preclude the serious impact of earthquake and disaster prevention and mitigation of the earthquake.In this thesis,based on the basic theory of seismic response analysis,taking a long-span PC cable-stayed bridge(Wushan Guihua Bridge)as an engineering example,the dynamic characteristics,seismic response spectrum analysis and time history analysis are carried out.The main contents in this thesis are as follows:1.According to the finite element analysis theory and Bridge Engineering knowledge,the three-dimensional finite element model of Wushan Guihua bridge for dynamic analysis is established,the key point is to accurately simulate the main girder section form and boundary conditions of the bridge,so as to accurately reflect the stress of the bridge structure and ensure the reliability and accuracy of the analysis results.2.Combining dynamic theory and using software MIDAS civil to analyze the dynamic of the bridge,which laid a foundation for seismic analysis research.3.The seismic response of Wushan Guihua bridge has been analyzed under two levels(E1,E2)and two conditions(vertical + vertical,horizontal + vertical)by using the response spectrum method,and the results of the maximum seismic response analysis were obtained.4.The seismic response of Wushan Guihua bridge has been analyzed to obtain seismic response values of the main control cross sections and nodes by dynamic time history method,and the results of the maximum seismic response analysis are obtained,simultaneously,compared with the results of the response spectrum method.