Abstract:Considering the bridge landscape and heavy traffic, the three-span variable-height continuous composite steel box girder bridge with the main span of 245 m is adopted in the project of the bridge approach of Jinan Fenghuang Yellow River Bridge across the levee, which is the largest span composite steel box girder bridge in the world. The main design features of this bridge include the highway, rail transit, pedestrian and non-motor vehicles are arranged on the same floor, and the maximum width of the bridge reaches 61.7 m, which realizes the concept of intensive utilization of bridge location resource and land. The girder is the innovative structural form combining the variable height center box chamber and the extra-large cantilever arm. The new UHPC-steel composite bridge deck structure is adopted in the carriageway area, which avoids the fatigue problems easily occurring in the steel bridge deck and reduces the structural weight. The design concept of allowing cracking without prestressing the bridge panel, but controlling the crack width is adopted for the concrete bridge deck at the top of the middle pier. The result of calculating and analyzing the steel girder, UHPC bridge deck and bottom slab concrete shows that the safety of the bridge structure meets the requirements of the code.
