Fall-Girder Construction Control Of Through Steel Tube Arch Bridge

Through steel tube arch bridge is a common kind bridge, it’s system conversion construction usually adopts the suspender tension method, suspender tensioning method has more mature theory and practical experiences, but there are disadvantages of complex cable adjustment processand long construction period. Fall-girder method conversion construction can avoid these disadvantages:jacking up the steel box girder rely on the temporary pier of girder, then stress free install all suspender, then fall the girder to complete system transformation. Falling-girder method dispense with repeatedly adjusting suspender force, can greatly shorten the construction period. Fall-girder method construction control is studied in this paper, mainly including the following aspects:1. Before the fall-girder construction, the analysis of finite element modeling and optimization control method is used, during the fall-girder construction, open loop control method, the maximum tolerance method is used. In order to obtain a set of control scheme used in fall-girder construction control.2. This paper lists three kinds of objective function model of fall-girder mehtod optimum control:The least square method, minimum energy method and girder-arch-suspender three control method. Three methods were used for optimization analyse of the same fall-girder construction examples, Comparison of three methods, the results show that girder-arch-suspender three control method is the best for fall-girder construction control.3. Taking the Dragon Bridge of Vietnam as example, guiding the construction by optimize and control the construction process, the results show that the construction control of Dragon Bridge achieved the objective, proves the rationality and feasibility of the control method.