Dynamic And Seismic Behavior Researches On Cured Girder Bridges

With the construction of city expressway and the rapid development of urban construction, highway interchange will increase in the city road network. In the construction of highway and railway, many curved bridges have been built in order to meet the demand of alignment or function. Curved bridges is an important component of the lifeline engineering. The failure of curved bridges during a severe earthquake can not only cause the heavy economic losses and casualties but also delay the rescue operations because the communication is broken. Therefore, it is necessary to study the influences of strong earthquakes on this kind of bridge. It can not only provide the theory basis for the bridge examination and the reinforcement, but also can enrich the earthquake data and experiences. As a result, there's important practical significance on this study.In this paper, analysis is made to a curved bridge with two methods:spectrum response analysis, elastic time-history analysis of earthquake. The main work includes:1. The spatial FE model is established by using the general-purpose FE software ANSYS;2.By adjusting the cures radius, bearing stiffness and support type of a curved bridge, the influence of those effect to the dynamic characteristics of the curved bridge are discussed;3. Two methods including spectrum response analysis and time-history analysis of earthquake are applied to the curved bridge, the internal force and displacement of this structure are obtained, By analyzing the response spectrum analysis and time history analysis on this curved bridges, the critical angle of input of earthquake ground motions are discussed.Through this study showed that for curved girder bridge, because of their space force characteristics, we need to pay attention to the condition of support,the strength of braking pier, stiffness of rubber bearings and the radius of plane curve. At the same time in the selection of a small curve radius, by considering the longitudinal and transverse of the curved girder bridges, the influence of different direction to the particular location must be considered.