Research Of The Effect On Shrinkage And Creep For Concrete-filled Steel Tubular Tied Arch Bridge

With the rapid development of concrete-filled steel tubular arch bridge in engineering construction,the concrete shrinkage and creep problem is widely concerned.Especially for concrete-filled steel tubular tied arch bridge,the effect of shrinkage and creep of the concrete both inside and outside of the steel tube should get more attention.Therefore,it is necessary to study the effect of the concrete shrinkage and creep,and emphatically analyze the influence which causes on the internal force,the stress and deformation of main components.The main research of this paper follows:(1)Based on the domestic and overseas research results of the shrinkage and creep to the concrete,the concrete-filled steel tubular members and the concrete-filled steel tubular arch bridge,the concept, generational mechanism and influence factors of shrinkage and creep are mainly studied.And the problems when analyzing the effect of shrinkage and creep of concrete-filled steel tubular tied arch bridge are cleared.The target,content and method that are required to study are determined.(2)Aiming at the widely used classical mode of shrinkage and creep both from home and abroad,the differences in structure form,influence factor and prediction accuracy are compared to analyze,as a result, each mode’s adaptability and characteristic is pointed out. According to the different features between the common concrete and the core concrete inside steel tube of concrete-filled steel tubular tied arch bridge,combined with the existing research results,adaptive shrinkage and creep mode to core concrete and common concrete(concrete of tie bar, floor system etc.)are recommended.(3)Based on a real bridge engineering sample,using a chosen shrinkage and creep mode,a finite element model is built to analyze the effect of shrinkage and creep,together and individually,on concrete-filled steel tubular tied arch bridge and the importance of shrinkage and creep cleared.The research finnaly deternined the relationship between “individual” and “interaction” on the basis of the caculation results analysis.(4)According to the influence factors of concrete shrinkage and creep,the influence factors of a real engineering from shrinkage and creep mode,construction method and structure forms and other aspects are analyzed.And the influence degree those factors could cause to bridge shrinkage and creep and some valuable laws are obtained so as to provide important references in bridge designing stage.