Study On Seismic Performance Of Three-span Continuous Through Type Concrete Skew Arch Bridge

With the rapid growth of rural economy, the demand for medium and small span bridges is increasing day by day. The concrete skew arch bridge is widely used in its reasonable structure and beautiful appearance. Without certain specifications in the current codes, the concrete skew arch bridge was destroyed by the earthquake more seriously than the right bridge according to the earthquake disaster data.Therefore, the research to the seismic performance of skew arch bridge is necessary and important.With the help of finite element software Midas/Civil and Midas/Fea, this paper built the model of 3*22m three-span continuous concrete skew arch bridge. Taking the skew angles as the variables,the paper conducts a study to the seismic performance of skew arch bridge, and the main research contents are shown as follows:1.To analyze the self-vibration characteristics,the mode of vibration and the coupled modes of three-span continuous through type concrete skew arch bridge.To research the influence of skew angels on natural vibration frequency, primary mode,coupled modes and mode mass participation percentage of skew bridge.Moreover,to analyze its changed tendency with skew angels.2.With conducting E1 response spectrum analysis, three-span continuous through concrete arch bridges were analyzed in different skew angles of dead load,transverse and longitudinal earthquake load combined action,and the internal force variation of mid-span plate elements,bridge axis plate elements, arch rib elements and piers elements were studied.3.To take Elcentro wave which has been adjusted by PGA as earthquake load of time history to analyze the internal force variation of three-span continuous through concrete arch bridges with different skew angles when they are affected by three direction seismic waves together,and analyzed the influence of single direction seismic wave.Besides,to conduct dead weight analysis and time-histories analysis with the condition of the example Tian Sha River vehicular bridge has studied the internal force influence of different direction earthquake loads on cross section.According to the seismic analysis result of three-span continuous through concrete skew arch bridge, the research result has reference significance for the seismic design of congeneric skew arch bridge and it is helpful to afford actual bridge engineering reference and experience.