Study On Dynamic Characteristics And Seismic Responses Of Beam-Arch Combined Bridge

Beam-arch Combined Bridge as a new form of bridge structure, combines the traditional arch and beam structure system together to resist force, can make full use of their respective advantages and avoid disadvantages. In recent years, with the development of economy, the theory of bridge design and construction technology, Beam-arch Combined Bridge with its beautiful shape, the unique mechanical characteristics, are more widely used in large-span bridges, especially high-speed railway construction. So the study of dynamic characteristics and seismic response of this type of bridge has important theoretical and practical significance.In this paper, based on the actual project, use the large numerical analysis software to created a 3D numerical simulation model. Study on the dynamic characteristics and seismic response of Beam-arch Combined Bridge. Finally using the response spectrum method and time history analysis method to studied on space dynamic response characteristics under earthquake. The mainly work in this paper include the following aspects:(1) Reviewed the generation and development status of Beam-arch Bridge. Analyze the mechanical force characteristics and advantages of such bridges.(2) Summarized the literature data about the status of seismic research and seismic response analysis methods on this bridge at home and abroad. Elaborated the importance and necessity of the seismic design of the bridge. Analyzed the characteristics of the current bridge seismic analysis method, such as static method, response spectrum method, time-history analysis method, and then select the appropriate theory and methods of this study need.(3) Based on actual project by means of the bridge software Midas Civil establish a three-dimensional numerical simulation model simulation space; to study the vibration characteristics of the combination system; systematic analysis the dynamic parameters sensitivity of this bridge, such as main arch rib rigidity, structural quality, boom type, the main beam support conditions and other parameters of the dynamic parameters sensitivity.(4) Based on actual project, with the response spectrum method to analysis Beam-arch Combined Bridge systems seismic response, focusing on effects of seismic displacements and internal forces of the key parts of the structure by seismic excitation direction. In addition, to further explore response characteristics under continuing earthquake action, the paper also uses time-history method targeted analysis seismic response analysis of Beam-arch Combined Bridge, and compared the calculation of the two methods above.