Research On Static And Dynamic Behavior Of Hybrid Grider Cable-Stayed Bridge In Twin Pylons

On account of the engineering background of Nanxi Yangtze River bridge in the Yibin city, the static analysis and dynamic analysis of hybrid grider cable-stayed bridge in twin pylons with the span of 280m+572m+198m was done in this thesis by using finite element software. The main research results and conclusions are as follows:(1)The thesis introduced the structural characters, development and existing problems of hybrid girder cable-stayed bridges together with the correlation anslysis theories and finite element analysis theories of cable-stayed bridges. At the same time, the engineering background, design schemes and the simulation analysis process of finite element model of the whole bridge was introduced in detail.(2)The stress condition of composite beam, static calculation & analysis of concrete girder, stability of finished bridge state and distribution of internal force and deformation condition of main beam was analyzed through the three-dimensional finite element model of the whole bridge. Meanwhile, the partial model of diaphragm plate was established by using DrBridge to study its carrying capacity and crack resistance. What’s more, the tower’s carrying capacity and stress condition, stayed cable’s stress status and fatigue properties were considered by the author.(3)Through the characteristic value analysis of the whole bridge finite element model, the main dynamic characteristics of the bridge span structure were obtained. According to the seismic properties of the site, the effect of E1 and E2 was carried out for the seismic response analysis in the thesis.Through the above analysis, the static, dynamic and stability of Nanxi Yangtze River bridge in the Yibin city meet the requirements of the specification and the design of bridge span structure is very reasonable.