Static And Dynamic Mechanical Performance Analysis Of CFST Stiffened Skeleton Arch Bridge

In the early 1990s.with the continuous development of the rigid skeleton construction method,the C.FST stiffened skeleton arch bridge gradually became popular in China.It has the advantages of strong spanning ability,large structural rigidity,small deformation,good dynamic performance and good economy.It is one of the most competitive bridge types in China's long-span bridges.Although the construction technology of the stiff skeleton arch bridge is relatively mature,the research in related fields is far behind the development of construction technology.In addition,the seismic response of long-span arch bridges is very complicated,and it is necessary to consider the influence of traveling wave effect.However,there is no seismic design specification for such bridge types.Therefore,it is of great value to study the seismic response of long-span CFST stiffened skeleton arch bridges.In this paper,a CFST stiffened skeleton arch bridge is used as the engineering background.The static and dynamic characteristics of the bridge type are studied.The influence of some parameters on the static and dynamic characteristics of the structure and the seismic effect analysis are carried out.The research contents of this paper are as follows:Calculating the static characteristics of CFST stiffened skeleton arch bridge under dead load,live load and combination load,and summarizing the regulations of displacement,internal force and stress distribution of the main arch.And they provide a reference for the design of CFST stiffened skeleton arch bridge.Researching the dynamic characteristics of CFST stiffened skeleton arch bridge.The influence of rise-span ratio,the width of the arch ring section,the diameter of the steel tube,spacing between arch and beams and the height of the arch ring section on the dynamic characteristics of the structure are discussed.Using response spectrum method and time history analysis method respectively to analyze the displacement and internal force response of CFST stiffened skeleton arch bridge and summarizing the seismic response regulations of this type of the bridges under different directions of seismic action and different wave velocities.Summarizing the influence of traveling wave effect on the seismic response of the structure by comparing the seismic response of the structure under uniform excitation and traveling wave effect.And these conclusions can provide a reference for seismic design.In summary,the static and dynamic characteristics and seismic response regulations of the structure obtained in this thesis have profound values for the design and application of this type of bridges by researching the main parameters and seismic response of long-span CFST stiffened skeleton arch bridges.