Analysis of Mechanical Behavior of Main Bridge of Jiubao Bridge

The main bridge of the Jiubao Bridge is a 3-span continuous composite tied arch bridge.Structurally novel,the main girder of the bridge makes use of the steel and concrete composite girder while the arches employ the outward inclined steel box arch ribs as main arches,the spatially curved steel box arch ribs as subsidiary arches and the structure of the bridge therefore manifests the complex spatial mechanical behavior.To have a detailed understanding of the mechanical behavior of the bridge,the finite element method is used to calculate the mechanical behavior of the bridge under different load cases and to reveal the mechanical behavior of different components of the composite arch bridge.From the analysis of the calculation,it is concluded that the global mechanical behavior of the bridge will be good,provided that the rational construction sequences should be followed,however,the stress distribution in the joints among the arches and girder is complex,to which sufficient attention should be paid.