Seismic Response Of Cable-Stayed Bridge With Single Tower And Cable Plane In Wenchuan Earthquake

With the scale of cable-stayed bridge enlarging,more and more attention is paid for the seismic behavior of cable-stayed bridge. Fujiangâ…£Bridge in Mianyang Bridge is a cable-stayed bridge with single tower and single cable plane, and the earthquake intensity of the situation of this bridge is VI, which is a very important part of the urban traffic system.Although experienced a 8.0 earthquake, it wasn't destroyed by the earthquake and showed good seismic performance. So analyzing and studying the earthquake response of this bridge is very significant. Based on the research results home and abroad, the dynamic behavior and seismic response of Fujiang IV Bridge are studied systematically in this thesis.Firstly, structure simulation of the components of cable-stayed bridge are elaborated in detail in this thesis,and then based on Fujiang IV Bridge, using the structural analysis program Midas/Civil 2006,the finite element dynamic model of this Bridge is established. The vibration characteristics of Fujiangâ…£Bridge is also analyzed, and the 10 frequencies and corresponding vibration models are gained.Taking the acceleration response spectrum curve in design as the spectrum input ones accordding to Guidelines for Seismic Design of Highway Bridges, the response of the bridge was calculated. And then, the general rules of seismic response of structure under waves in longitudinal, transverse, vertical direction and their combination are obtained. In order to ensure the accuracy,the CQC(Complete Quadratic Combination) method is applied.Artificial seismic wave are gained accordding to the design acceleration response spectrum and compatible with the design of synthetic acceleration time history, using which dynamic time history response analysis of Fujiangâ…£Bridge are researched.On the comparison of results of dynamic time history analysis and response spectrum method, the influence on the structure is presented as conclusion, and applicability of response spectrum mehod for this bridge is evaluated scientifieally.Finally, using Wenchuan earthquake wave, the seismic response of Fujiangâ…£Bridge is analyzed.These research can be used as the seismic design basis of the Fujiangâ…£Bridge,and also can be used for directing seismic response analysis in other bridges of similar kinds.