A Study on Behavior of Continuous Steel Box Girder Bridges Constructed by Applying Up-Down Construction Method

The purpose of this paper is to investigate the behaviour of steel box girder bridge during up-down construction method. The steel box girder with open-trapezoidal cross section, partial prefabricated concrete slab and double composite section by cast-in-place bottom concrete slab is considered in this study. The three-dimensional finite element (FE) models, considering construction sequence in modelling, have been used to carry out the analysis. A parametric analytic study is used to investigate the effects of some structural characteristic on the behaviour of steel box girder. These parameters include the variation of lifting upward and lowering downward height, the length and depth of bottom concrete slab and the length of partial pre-fabricated concrete slab. An overview of the effect of lifting upward and lowering downward method to the stability design such as web buckling and top lateral bracing are also given. Results of the study with potential design recommendations are outlined.