Analysis On Girder-arch Association System And Construction Control

Girder and arch associate bridge is a practical type of structural form,which is not only beautiful in shape,but also with the advantages of reasonable economy,convenient construction and great spanning ability.It is popular with the engineering designers of the bridge.The girder and arch associate bridge has a wide range of practical applications.It can be used for crossing river and valley areas and for urban landscape bridges.In the development process of the girder and arch associate bridge,the research results are not deep enough,aiming at single research object,especially on studying how to determine the reasonable loading state,some of the important influence factors including bearing ratio of cable and girder to distribute load?static performance ?stability and how to determine reasonable derrick force,in the early stage of the design designer needs to determine bearing ratio of cable and girder,the static characteristics ? stability and reasonable derrick force can ensure safety and reasonable operating linetype.In order to solve these problems,researchers have invested a lot of resources in the study of girder and arch associate bridge,and have obtained many research results.However,most of the related research results are obtained by means of numerical calculation,and the research object is only for the one bridge of girder and arch associate bridge,which makes the scientific research results fail to form a series and the scope of application has some limitations.The main research work in this paper is as follows: (1)The domestic and foreign development of girder and arch associate bridge in China and abroad is expounded by consulting the documents,and the research achievements in the development of the girder and arch associate bridge are combed,and the existing problems of the existing research results are pointed out,which is the main research content of this paper.(2)According to the girder and arch associate bridge,it is divided into the simple supported or the continuous girder and arch associate bridge arch cooperative system bridge,and the calculation formula of the live load ratio of the above two structural systems is derived by the analogy girder method and the deformation coordination equation.(3)The lifting force is regarded as the uniform membrane tension,and the approximate analytical solution of the structural system is solved by the method of structural analysis.The analytic solution of the static stability and the fundamental frequency of the bridge is derived by the energy method,and the analytical solution is checked with the numerical solution to verify the analytical solution effectiveness.(4)According to the stress balance principle of the upper and bottom edge of the arch ribs,the feasible region of the stress of the arch ribs under the constant load is deduced,and the feasible domain is the constraint condition,and the force of the hanger is adjusted to make the force of the bridge of the beam arch cooperative system be in a reasonable state.(5)Taking one bridge as a typical case,the vertical rotating body is finely analyzed with the help of numerical analysis,and the influence of the cable force on the alignment of the arch ribs is studied.Through the above research ideas,the following work is completed in this paper:(1)The validity for the calculation formula of the live load ratio of cable and beam is verified.The parameters of live load ratio of Girder and arch associate bridge are analyzed(2)The approximate calculation formula of deflection calculation is derived under the action of constant load and live load.The approximate calculation formula of lateral instability of the arch ribs is derived.The estimation formula of lateral vibration fundamental frequency of girder and arch collaborative system is derived by volume method. (3)According to the stress on the upper and bottom edge of the arch rib,using the stress balance method,determine the reasonable derrick force.It is furtherprove that in order to accelerate the convergence speed,the minimum bending strain energy principle can be used to determine the initial tension force of the suspender.From the mechanical point of view,the reason that the bending moment value of the arch and arch foot section is larger than that of other sections under the constant load is explained.At the same time,the reason that the suspension force of the bridge side of the bridge is larger than that of the other hangers is explained at the same time.