Research And Optimization Of Arch Ring Construction Technology For Large Span Stiff Skeleton Arch Bridge

With the development of large-span arch bridges in China,its construction technology and calculation theory have been continuously improved and updated.Since the stiffness framework of the Yongning Bridge in Yongning,Guangxi has been constructed by cable hoisting and cable-staying method,this method has gradually become one of the main construction methods for the construction of large-span arch bridges.Many researchers have carried out a lot of research in the cable force and linear control of the cable stay.Although many of the theoretical research results can accurately guide the construction,they also have their own limitations.In the research of determining the pouring concrete pouring scheme,usually different pouring schemes are drawn up first according to the actual construction situation,and then the construction simulation analysis is carried out to determine the best scheme.Therefore,further research is needed in the construction technology of the stiff skeleton arch bridge.Based on the stiff skeleton concrete arch bridge under construction-Nuozhadu Lancang River Extra Large Bridge,this paper mainly develops the following the study:(1)First,it summarizes the development process of arch bridges and rigid skeleton arch bridges,then summarizes the current calculation method of cable force of cable stays,the influence factors of arch rib line shape,and the current research status of outsourcing concrete pouring technology.Engineering background.(2)The composition of the cable hoisting system is briefly described.The stiff skeleton arch rib section uses the cable hoisting method of cable hoisting buckle to hoist the basic process of construction and several pouring methods and technologies of the outsourcing concrete.Summarizes the current commonly used theory of cable force calculation for cable stays,and analyzes the advantages and disadvantages of each calculation theory.(3)The structural optimization calculation theory is used in the calculation of buckle cable force,and an optimized mathematical model for solving the buckle cable force is established.The buckle cable force optimization calculation program is written using the ANSYS parameterized design language.First-order optimization algorithm to solve the optimal cable force value.(4)Contrast and analyze the difference in the influence of section joints using consolidation and articulated hoisting on the arch rib line shape.The research deduces the calculation formula of the influence of the tower deflection and temperature change on the elevation of the section control point.By considering these influencing factors Correct the installation pre-lift value of the arch rib segment.(5)Based on the influence line loading method to determine the segmented loading sequence of the outsourcing concrete pouring,the ANSYS finite element software and the Origin mathematical tool are used to fit the expression of the line function of the stiffness skeleton arch deflection,which is obtained by the Mathematica mathematical tool integration Deflection deformation value of the dome section caused by each pouring section.Based on the basic principle of influencing line loading,the segmented loading order of pouring concrete is determined according to the deflection deformation value.