Analysis On Seismic Response Of Double Cable Plane Cable-stayed Bridge Of (46+88+280+88+46)m

Cable-stayed bridge has much more outstanding performance in spanning capacity than other beam bridge with its clear force transmission path, beautiful structure shape, large spanning capacity, beautiful shape, strong seismic performance characteristics, and has become one of the main style of long-span bridges in our country. China belongs to earthquake-prone countries. Once a long-span cable-stayed bridge destructs in an earthquake, it will cause immeasurable loss. Thus seismic analysis for long-span cable-stayed bridge is extremely important.Taking Xi Nan Bridge as the engineering background this paper conducts a research on the following aspects of the seismic response of the cable-stayed bridge :(1)The bridge seismic analysis methods: the principle and calculation method of static method, response spectrum method and time history analysis method are expounded.(2)Based on the background of Xi Nan Bridge, establish finite element model with MIDAS/CIVIL and analyze the influence of pile soil interaction on natural vibration characteristic of cable stayed bridge. This paper takes the cable-stayed bridge self vibration characteristics under consideration of pile soil interaction as the basis of analysis of dynamic response and seismic.(3)This paper carries on the analysis of response spectrum under uniform excitation of long-span cable-stayed bridge and discusses the seismic response in the three kind of seismic load combination condition, summarizing the impact of seismic input on the long-span cable-stayed bridge computational results.(4)Select three earthquake wave as seismic input and conclude the seismic response of this bridge is maximum under the Chi-Chi wave. Then carry on dynamic time history analysis on excitation of the structure calculation, and compare with the response spectrum method.(5) Analyze the traveling wave effect on seismic response of the structure,comparing the seismic response under uniform excitation and non-uniform excitationat 400 m/s. It is concluded the effect on the seismic response of the bridge on traveling wave at velocity of 400 m/s.