Cable Force For Hoisting Steel Pipe Concrete Arch Bridge Analysis And Control

Concrete-filled steel tube arch bridges have developed rapidly in my country due to their long spans and beautiful shapes.They are one of the more commonly used bridge structures.However,there are relatively few researches on the application of the stress-free state method in the construction control of concrete-filled steel tube arch bridges.The stress-free state method is one of the calculation methods of construction control.It uses the stress-free state quantity to connect the construction process and the completed state of the bridge.It has the characteristics of clear concept,convenient calculation,and large construction freedom.To this end,this article has carried out the following research on the construction control of the concrete-filled steel tube arch bridge using the stress-free state method:(1)Expounds the historical origin of the concrete-filled steel tube arch bridge and the evolution of construction method,and introduces the construction control and free of stress state of the development process of the method in the application.(2)From the basic theory of this paper,the derivation method of stress state of the two stress free state: curvature and unstressed length without stress.Compared with other methods,and summarizes method of stress state when dealing with the calculation of construction process is unique.The stress free state method in the construction of the arch bridge concrete implementation process,has made the detailed overall planning.To stress free linear hoisting construction model is set up,through the analysis of the dress,for the installation of the arch rib alignment.(3)The finite element model for the construction of the Lancang River Bridge was established using finite element software,and the pre-camber of the key positions of the arch rib was obtained by the combination of upside-down disassembly and forward installation,and the stress-free linear shape of the arch rib was obtained by linear fitting.(4)Introduces the application in the cable-stayed bridge bridge in line of minimum bending energy method,and the method for arch bridge construction into calculation of completed bridge.Through the comparison and analysis with finite element zero displacement method,show that the method is applied to the feasibility of the calculation of arch bridge construction.And then using the ideas of stress free cable long dress iteration,stress free cable length as main parameters in the input model.Solution to satisfy a set of the construction process of tensioning construction suits and put the important control parameters of cable force for actual construction.(5)Analyzes in detail the effects of temperature change to the arch rib hoisting construction,respectively analyzes the environmental temperature on the tension control during the construction of cable force,the influence of upstream and downstream.In the research on these three aspects are discussed in this paper,and on how to eliminate the influence of temperature on these correction scheme is proposed.(6)In lancang river extra-large bridge as the engineering background,by the method of no stress state,the bridge construction monitoring.The field measurement data comparing with the theoretical calculation results,and has achieved the results of the monitoring requirements.