Seismic Response Analysis Of Long-Span Composite Girder Cable-Stayed Bridge

It is well kown that the long-span bridge is one of the most important traffic life line projects. Therefore the correct and effective design of earthquake resistance is of great importance to the safety of cable-stayed bridges.In this thesis, a long-span composite girder cable-stayed bridge—Jiangjin Guanyinyan Yangtze River Bridge is investigated, based on the basic theory of the seismic response analysis, making spectrum response analysis, time-history analysis and ductility design analysis. The main contents in this thesis as follows:1. Based on the theory of finite element, a spatial finite element model of the long-span composite girder cable-stayed bridge is established, using the finite element analysis program ANSYS. The dynamic characteristics of two models are analyzed, including the cable-stayed bridge with piles and the non-pile cable-stayed bridge.2. The theory of the seismic response spectrum analysis is introduced briefly.The composite girder cable-stayed bridge model are analized under two different boundary conditions:with or without piers, employing response spectrum method, to discuss the influnce of the interaction of pile-soil simulated by soil spring. Through the above analysis, providing reference for seismic design and analysis of the long-span cable-stayed bridge.3. For simulation the vibration process of the bridge, the cable-stayed bridge model with or not pile are analized employing time history analysis method,and the displacement and internal force process curves of key positions will be shown. Through the analysis, providing reference for the long-span cable-stayed bridge.4. The ductility theoretical basis ,which is the second phase of the bridge seismic design,and the influence factors of ductility is introduced briefly. And calculating the plastic hinge which is an important factor influenced the bridge ductility. The dynamic characteristics of the ductility model is analyed.