Analysis For Structural System Of Partially Ground-anchored Single-tower Cable-stayed Bridge

As a kind of cable-stayed bridge,partially ground-anchored single-tower cable-stayed bridge has been applied in practical engineering because of its beautiful structure and large rigidity.However,its structural form is different from ground-anchored cable-stayed bridge and single tower cable-stayed bridge,the mechanical behavior of the structure is different from the conventional single tower cable-stayed bridge.Therefore,this paper focuses on the analysis of structural system of partially ground-anchored single-tower cable-stayed bridge.In this paper,based on a building partially ground-anchored single-tower cable-stayed bridge,the finite element method is used to analyze the structural system.Making floating system,rigid frame system and supporting system under the condition of consolidation or hinge of main beam and ground anchor as the change form.Comparative analysis of the bridge displacement of tower top,girder deflection,axial force of girder,maximum span moment,the moment of tower bottom under the action of permanent load,live load,temperature load.Under the girder and anchor consolidation conditions,the structure of supporting system is reasonable,in the girder and anchor hinge case,the rigid system is more reasonable,floating system is not suitable for use in this type of bridge structure.Then the comparative analysis of grand-anchor system and partially grand-anchor system of the key points displacement and performance under four kinds of load,get the grand-anchor system performance is better partially grand-anchor system.In view of the structural arrangement and the force complexity of the partially grand-anchored single-tower cable-stayed bridge,this paper selects some design parameters for the mechanical analysis.Analysis of the tower cable spacing,ratio of side to main span,stiffness ratio of beam and tower,the ratio of tower height to span of four design parameters by using the finite element method.Through a certain range of parameter changes,comparative analysis of the key points of the displacement and internal force under the permanent load,live load,temperature load,obtain structural mechanical properties rule under different design parameters.According to the original design parameters of the project,the paper gives the reasonable optimization suggestions.Finally analysis the sensitivity of the design parameters,obtain the sensitivity ranking results of four design parameters in the key mechanical indexes.