Research On Local Structure Of Flat Steel Box Girder

In the past 20 years, with the development of long span bridge, the flat steel box girder was widely used. Though the flat steel box girder has been applied for 40 years, some problems of this type girder is still worth to research. In this thesis, the north channel bridge of Zhujiang Huangpu Bridge is taken as a numerical example. And four parts are studied in the local structure system of flat steel box girder,by FEM:(1)The development and present situation of flat steel box girder is recounted.(2)The force of diaphragm in hunging point and diaphragm in unhunging point is analyzed. And the rule of stress is presented. The influence of stiffeners of top and bottom plate and cable force is also analyzed. The reasonable position of hole in diaphragm is also presented.(3)The stability of diaphragm in unhunging point under the force of vehicle is analyzed. The stability of diaphragm with different stiffeners distribution is compared, and a reasonable and economical stiffeners distribution is presented.(4) During the construction stage, lifting segment, the transverse deflection of segment to be lifting is opposite of segment supporting crane, thus the problem is produced during segment connection. Calculating about this is done in the thesis. The influence of uniform temperature, non-uniform temperature, longitudinal plate location and longitudinal plate stiffness is investigated and some optimization measures are presented.(5) The force of longitudinal plate of segment supporting crane under the huge force of crane, when the segment is lifted, is calculated in this thesis, and it is discovered that the force of longitudinal plate has been beyond the limition, when it is designed in usual way. Some optimization measures are also presented.We hope the researchment in this thesis can provide reference for flat steel box girder design and construction.