Study on force of steel bracket for construction of large span and wide steel box girder

Abstract

Dongping waterway bridge is a steel concrete composite single-tower cable stayed bridge with spans of 35+260+50+64+66 m. The bridge M21-M31 beam section is constructed by steel pipe bracket. The Steel pipe column is designed for transverse bridge to 2 groups of 4 rows, each 2 rows connected into a group, and the steel pipe column is connected through the profile steel connection system. The top of steel pipe column is equipped with profiled steel beam, the profiled steel distribution beam is equipped with bailey beam and I-beam, and the longitudinal moving push-up slideway of the steel box beam is installed on the I-beam. In order to check the safety of steel pipe bracket in construction stage, the finite element model of steel pipe bracket and the field measured steel pipe stress are established by MIDAS software. The results show that the force and alignment change of the steel bracket construction used in this bridge is reasonable. In addition, through the finite element optimization of the existing bracket, it is proved that the optimized steel bracket structure can save 20% steel consumption under the premise of ensuring safety, which provides a reference for similar projects.