Analysis Of Static And Dynamic Characteristics On Long Span Curved Cable-stayed Bridges With Roads And Tracks In Same Floor And Its Steel Box Girder Web Layout Study

Curved cable-stayed bridge is a cable-stayed bridge that its main girder arranged curvedly to fit the curved lane.Because of the curved main girder,its "bending-torsion coupling effect" is obvious.Curved cable-stayed bridges with roads and tracks in same floor has the characteristics of both curved beam and rail-cum-road,this makes the stress on main girder very complicated.At the same time,due to the complexity of spatial arrangement of cables and pylons,the stress state of curved cable-stayed bridge become more complicated.Therefore,it is necessary to conduct an in-depth analysis of the static and dynamic characteristics of the long span curved cable-stayed bridge with roads and tracks in same floor.In this paper,a long-span curved cable-stayed bridge with roads and tracks in same floor under design in China is taken as the background to establish a finite element model and analyze its static and dynamic characteristics and the influence of steel box girder web layout on the structural stress.This article mainly carried on the following several aspects work:Firstly,this paper expounds the current status of construction and research of curved cable-stayed bridges and rail-cum-road cable-stayed bridges at home and abroad.And analyzes the significance of the thesis topic.Secondly,based on the finite element software Midas Civil,the space girder finite element model of the bridge in this paper is established.The important links in the modeling process of long span curved cable-stayed bridges with roads and tracks in same floor are described.Thirdly,the basic principle of grillage method is elaborated.Based on the finite element software Midas Civil and Midas Fea,the spatial grillage and shell element models of the main girder segments of the background engineering bridge are established,and the calculation accuracy of the spatial grillage method is analyzed.Fourth,through the calculation of the space girder model of the bridge,the deformation and stress characteristics of the curved cable-stayed bridge with roads and tracks in same floor in the operation stage are analyzed and studied.Fifth,the response spectrum analysis and time history analysis of background engineering bridges are carried out.The structural response characteristics of long-span curved cable-stayed bridges with roads and tracks in same floor under earthquake are analyzed,and the calculation results of these two methods are compared and analyzed.Sixth,according to the characteristics of the bridge,this paper studies the web layout on the force and deformation of steel box girder under train load,and offers optimization advice for background bridges.