Research On Seismic Response Of Hybrid Girder Cable-Stayed Bridge Of700M Main Span And Its Parameter Optimization For Fluid Viscous Dampers

In this thesis, according to the design of Jiangshun Bridge, a hybrid girder cable-stayed bridge of700m main span with double pylons and double cable planes, three dimensional finite element models are established using finite element analysis software MIDAS/CIVIL2011. Meanwhile, free viberation characteristics, seismic response and parameter optimization for fluid viscous dampers of the bridge are investigated. The main contents in this thesis are following:(1) Three dimensional finite element model of hybrid girder cable-stayed bridge with and without piles and soil are established. Free viberation characteristics of these two models are analyzed and compared.(2) Both the response spectrum method and time-history method are applied to study the seismic response of hybrid girder cable-stayed bridge with and without piles and soil, therefore, the results from these two methods are compared and discussed thoroughly, the influence of the pile-soil-structure interaction to seismic response of the bridge is studied.(3) The seismic response of hybrid girder cable-stayed bridge under travelling wave effects is analyzed. The response of longitudinal deformation of tower top and main girder, the response of axial force, shear force and bending moment of tower bottom under four different wave velocity are compared and studied.(4) The non-linear time-history method is applied to study the aseismic performance of hybrid girder cable-stayed bridge with fluid viscous dampers. Furthermore, the parameter of damping coefficient C and damping exponent ξ is optimized. Finally, a set of optimal parameter of fluid viscous dampers for Jiangshun Bridge is proposed.