Research On The Seismic Response And Shock Absorption Of Five Span Continuous Arch Bridge

Arch bridge has a long history in China. Because of its big stiffness, wide spanning capacity, beautiful model and diverse structure characteristics, it has been one of the firs-chosen bridge constructions. The seismic problems of the arch bridge are related to people’s life safety and the earthquake seismic rescue work, therefore, the analysis of its seismic response has very important significance. At present, there is no specific and clear regulation about the seismic problem of big span-steel arch bridge in our country, and the relevant literature is seldom seen. PuWan new district sea-crossing Bridge in Dalian is a steel arch bridge across the5-span girder wings, with its bridge span640m and width of bridge deck46m. This paper takes PuWan new district sea-crossing Bridge as the background, and studies the vibration characteristics, seismic response analysis and damping control of the large span steel arch bridge in the following aspects:(1) This paper analyzes on the basis of reviewing the literature, understanding the bridge structure earthquake, the present situation of earthquake response of the bridge structure vibration damping measure and control method analysis of the bridge structure.(2) This paper constructs finite element model of the whole bridge through the structure analysis finite element the general program MIDAS/Civil software and conducts dynamic analysis. Through the extraction of the12order on vibrating modal analysis, it studies the vibration characteristics of bridge structure, and takes this as the foundation structure of dynamic analysis.(3) According to the seismic intensity, basic earthquake peak acceleration and characteristics of PuWan new district sea-crossing Bridge, this paper selects the three cycle waves, and conducts nonlinear dynamic time history analysis. Meanwhile, it comparably analyzes the time history analysis results and summarizes the statistical law of the results, considering the response of the structure under the combinations of horizontal and vertical seismic waves.(4) It introduces the viscous dampers damping technology progress and the principle of energy consumption and introduces four main restoring force model of viscous dampers in detail, namely linear model, Kelvin, Maxwell and Wiechert, and meanwhile introduces the range of restoring force model. On the background of PuWan new district sea-crossing Bridge, this paper introduces influence of the damper parameters selection to the earthquake response of the structure, and selects a damper parameters according to the principle of selection. It also analyzes the shock absorption effect of structure after setting parameters set viscous dampers. The results show that the main girder is effectively controlled by the set viscous dampers.