Study On The Design Of Arch Structure Of Six-tube CFST Arch Bridge

The concrete-filled steel tubular arch bridge is divided into single-limb and multilimb type.The most common is single limbs and four-body limbs,Only the Guangzhou Yajisha Bridge built in 2000 and the Xiaohe bridge built in 2009 was six-body CFST bridge,Therefore,it is necessary to study the structural design of the six-body concretefilled steel tubular arch bridge.In this paper,the following research work is carried out on “the structural design of the concrete arch bridge of the six-body concrete-filled steel tubular arch bridge”,which is aimed at the research and development of the main arch structure,concrete pouring and maintenance countermeasure of the incense and rock bridge project of Guizhou Provincial Transportation Department.Firstly,according to the principle of force mechanics of structural mechanics,make a reasonable reduction to arch hinge tilted belly poles,and derived the relationships between the angle and structural internal force as well as stability,it also put forwardand the reasonable range of the angle.Use the finite element software Midas to establish the full bridge model and verify the theoretical formula.According to the research results,put the arch hinge tilted belly poles structure optimize,and compared the strength and stability of the whole bridge before and after optimization.Secondly,based on the elastic stability theory,derived the formula of the lateral load bearing capacity of the single-limb double-rib arch,and studied the influence of the transverse structure on its elastic stability.By analogy,studied the influence of the position,pattern,stiffness and arrangement of the six-leg concrete-filled steel tubular arch bridge on the elastic stability.According to the research results,optimized the transverse brace and contrast the stability of the completed bridge before and after optimization.Thirdly,based on the existing ultimate bearing capacity formulas that consider separately the confinement index,initial stress and concrete creep.Using mathematical analysis to complete further deduction on the basis of these formulas.Put forward a method of steel ratio range of values.According to the research results,optimized the wall thickness of Xianghuoyan bridge and contrast the strength,rigidity and stability of the main arch structure under different construction stages before and after optimization.