Seismic Performance Analysis For Long-span CFST Stiff-Skeleton Arch Bridge

Because of the interaction between concrete and steel tube, which enhances the compression performance of concrete and improves the stability of steel tube, CFST Stiff-Skeleton shows good mechanical properties. On the other hand, the CFST Stiff-Skeleton providing a convenient construction platform for the construction of arch bridge, which made the construction of long-span arch bridge possible. So CFST Stiff-Skeleton Arch Bridge has been rapidly developed at home and abroad. Those good performance giving the CFST Stiff-Skeleton Arch Bridge a good mechanical performance and practicability, so the CFST Stiff-Skeleton Arch Bridge is widely used in practice. Therefore, research on seismic performance of the CFST Stiff-Skeleton Arch Bridge has important practical significance and practical values.This thesis, firstly, briefly introduced the development and achievements of CFST Stiff-Skeleton Arch Bridge, following of explanation of basic theory of dynamic characteristics and the finite element method for seismic analysis. The Jailing River Bridge in Zhaohua of Guangyuan city which is under construction currently was selected as the case study, the analysis model was established by using of Structural Analysis Program Midas/Civil 2010, the seismic performance analysis of long-span CFST Stiff-Skeleton Arch Bridge was studied as follows:(1). Through the analysis of the dynamic characteristics of this bridge, the general dynamic characteristics of long-span CFST Stiff-Skeleton Arch Bridge were expounded, and its vibration modes were given. By comparing of the dynamic properties of bare arch and full-bridge, the foundation for seismic analysis and research of long-span CFST Stiff-Skeleton Arch Bridge was established.(2). The development of methods and theories of Response Spectrum Method was described. Through the elastic response analysis of level E1 and E2 which is prescribed by Guidelines for Seismic Design of Highway Bridges (JTG/T B02-01-2008), the seismic performance of this bridge was researched.(3). By using of Time History Analysis Method, the seismic performances of this bridge under El-Centro wave and Wenchuan earthquake wave were analyzed respectively. The internal forces and displacements of this bridge were determined and analysis results were compared with the response spectrum method.The study of this thesis has some reference values for the design and construction of this bridge and seismic performances of this kind of bridge.