Static And Dynamic Analysis Of The Long Span Half-through Steel Box Arch Bridge

The space effects of half-through steel box X-type arch bridge are obviously，and theloadings of that are complex. Bridge designers are issue that how to analyze this type ofbridge, as he characteristics and rationality of its force structure, etc.This paper is taking Chongqing Beibei Chaoyang rebuilding bridge for theengineering background. Base on finite element analysis theory. Take the use of Midas,the large finite element software, build space finite element model for analyzing thestatic and dynamic characteristics of half-through steel box X-type arch bridge.First, this paper summarizes the development history and stress characteristics of thesteel box X-type arch bridge. This paper also summarizes the static and dynamiccharacteristics，research status of construction technology and existing problems both athome and abroad.Second, this paper introduces the theoretical foundation of the finite element analysis.Use Midas, large finite element software, establish space finite element model ofChaoyang rebuilding bridge,and then analyze the static performance under action of theconstant loaded, car loaded and temperature effected in bridge state. Find thattemperature effect on the deflection influence of arch rib is larger than the auto loads.Nonlinear calculation results show that geometry nonlinear of big span steel box X-typearch bridge have bigger effect.Then, author analyses the dynamic characteristics of structure. The results show that:the vibration of steel box X-type arch bridge mainly has three vibration types.Separately is Flexural vibration in the longitudinal symmetry plane of bridge, Torsionvibration and lateral bending, this is perpendicular to the same plane. The presence ofthe arch rib of the stiffness is relatively small, first appeared in vibration arch rib of thesurface vibration.Finally, analysis the reason of the steel box arch defects appeared in prefabricated andconstruction in the factory. And analysis the influence of the arch rib joint dislocationarch rib axial force, rib axial moment value, rib axial deformation and rib axial sectionstress. At last, put forward measures to treatment the defects.The study results in this paper provide basic data for health inspection andmaintenance of the bridge in the operation process. And also provide the valuablereference to design and construction for the same kind of bridge.