Research On Mechanical Performance Of Partial Concrete Steel Pipe Truss Arch Bridge

In recent years,concrete-filled steel tubular arch bridge in China's rapid development,its design and calculation theory is also constantly improving.At present,the national norms,industry norms and local standards have been promulgated ab the concrete-filled steel tubular arch bridge,one of the most important milestone event is in December 2015,the State Ministry of Transportation officially promulgated concrete-filled steel arch bridge design specifications,namely "Design specifications JTG/T D65-06-2015,so that the design of concrete-filled steel tubular arch bridge has a set of specialized specifications.The focus research of this paper is the analysis of the influence of the length of the pouring range of the CFST arch bridge on the mechanical properties of the arch ribs.The length of the concrete in the arch of the main arch is not only influence the material consumption and the project cost of the whole bridge,but also influence the mechanical performance of the main arch under the limit of normal use and load capacity.In order to study the influence rule of the length of concrete infiltration range on the mechanical performance of long-span concrete-filled steel tubular arch bridge,provide reference for the designer to choose reasonable infiltration range of the arch rib steel pipe new design ideas about concrete-filled steel tubular arch bridge.The finite element analysis model of Midas space is established based on?Design Code for Concrete Filled Steel Tubular Arch Bridge of Daxiaojin bridge,The change law of force performance about the concrete of the arch ribs and the concrete in the concrete in different arch ribs by comparing the length of the concrete are studied.The main research contents are as follows:(1)Based on the actual engineering,the finite element analysis model is used to analyze the mechanical performance of long-span CFST arch bridge,which lays the foundation for the study of the performance of some concrete truss arch bridge.(2)The mechanism of the effect of the length of concrete infusion on the length of the force was studied.In order to study the influence law of the length of concrete infiltration on the force of concrete in arch rib steel pipe and concrete in large span concrete-filled steel tubular arch bridge,the construction process of concrete-filled steel tubular arch bridge was simulated.The four-stage stress superposition method was used to analyze the effect of concrete infiltration range Mechanism,and the corresponding stage formula is deduced at the same time.(3)The influence of the length of concrete infiltration range on the mechanical properties is analyzed.This paper analyzes the influence law of the length of concrete infiltration range on mechanical performance of the concrete in the arch rib steel pipe and the concrete for the long span concrete-filled steel tubular arch bridge,and discusses the feasibility about how to reduce the proportion of structural weight to improve mechanical performance by reducing the length of the concrete infiltration rang.