The Aseismatic Analysis Of Different Structural System Of Single Pylon Cable-stayed Bridge

As a kind of old but young bridge, cable-stayed bridge has injected new vitality for bridge, the single pylon cable-stayed bridge has only one cable tower. In recent years because of its beautiful, economy and the characteristics of large span, it is getting more attention and developing rapidly in China. Although the number of single pylon cablestayed bridge and span is growing rapidly, but due to its short history, limited stand of the earthquake, the relevant seismic damage information is less, the research of its dynamic characteristics and seismic response analysis results is not enough. Cablestayed bridge as an important transportation hub project, because of its large investment and the importance of the economy, once it is destroyed, will cause huge economic losses. In the design of cable-stayed bridge, seismic analysis must be done and chose the most reasonable structure system, in order to reduce and avoid the effects of the earthquake.This paper discussed the commonly structure of the single pylon cable-stayed bridge and their respective characteristics. We use the Midas Civil software and the Hunchun bridge as the engineering background, to do the dynamic characteristics and seismic analysis. And mainly did the following aspects:(1)Summarized the research status of the single pylon cable-stayed bridge and the seismic research present situation at home and abroad, discussed the different structure of cable-stayed bridge method and their respective characteristics.(2)Combined with the actual project of Hunchun bridge, the paper discussed how to select the appropriate structure to establish finite element model of the bridge. Change the way the connection between the column, beam, pier to get four systems: floating system, half floating system, beam consolidation system and rigid frame system.( 3) Do the dynamic characteristics get the bridge dynamic characteristic. According to the specification to select suitable seismic wave, using the dynamic time history method to do seismic response analysis, recording different structure system response time history, comparative analysis and summarize the response regularity, choose the most suitable for Hunchun bridge seismic structure system.(4)In the case of half floating system, adding damping device and do the earthquake response analysis. Comparing with the undamped half floating system and rigid frame system, we found that its displacement change is very small and reduced the internal force response. This suggests that the damping device improved the integrity of the structure and vibration resistance, has played a very good effect on the structural integrity.In this paper, the research results can be used as a reference for this kind of bridge seismic design, and has certain guiding significance.