Nonlinear Dynamic Characteirstics Ifnite Element Method Analysis Of Large Span Concrete Cable-stayed Bridge

Since nearly half century, cable-stayed bridge design, construction, monitoringtheory and technology has made rapid development, by contrast, cable-stayed bridgedynamic analysis work backward. With cable-stayed bridge span increasing, thestructure becomes more light of today .the study of dynamic characteristics onCable-stayed bridge ’s fighting the wind and seismic is very urgent. Cable-stayedbridge have significant differences in the general structure of the system andmechanical properties of materials with the other beam bridge, which has its owncharacteristics about the wind, seismic performance, as well as vehicle vibrationperformance, and so on.Taking the KangBo super major bridge in SiChuan as an instance, this paper hasa further research around the analysis of dynamic characteristic and Seismic Responseof cable-stayed bridge on the foundation of existing research.KangBo bridge is taken as an example to establish two space dynamic calculaingmodels with ANSYS (single girder and three main girder). And detailed description ofthe dynamic characteristics. and the influence of primary structural parameters, suchas main girder structure form, diaphragms ,Auxiliary Pier and cable layout density, tothe self-vibration characteristics is analyzed through the application of the finiteelement analysis software. The results show that, compared to the single ribcross-section , the double main rib section has the enhancement to the bridge resisttorsion’s performance. The impact of diaphragms on the bridge dynamiccharacteristics calculation results is very small. Auxiliary Pier have a certaininfluence on cable-stayed bridge dynamic characteristics, mainly reflected in thein-plane vibration, cable-stayed density mainly affected the in-plane frequency, i.e.,vertical vibration.The study of cable-stayed bridge dynamic property provides fundamental theoryfor aseismatic design, wind resistance and analysis of vehicle vibration. Through theanalysis of dynamic, it can reveal more truly the structure stresses and deflectionunder the effect of vehicles. Then it can figure the responses of bridge structure whenearthquake and wind loads affected.The time-history analysis and the response spectrum method applied to thecable-stayed bridge, establish single girder model, compare and analyze the situationof the time analysis of them under along the bridge to vertical seismic waves.