Abstract:Research purposes: As the roof plate,bottom plate and web of steel box girder are rather thin,the distortion stress easily happens due to their deformations in the sections under the effect of the eccentric load,resulting in the local buckling and web crinkling. In engineering application,a certain amount of diaphragm plates are installed in the .box girder to restrain the distortion deformation and reduce the distortion effect on the box girder. There is a small number of papers to study the effect of the diaphragm plate on the distortion deformation of the steel box girder, but these papers do not research the distortion effects on steel box girder under the conditions of various amounts of the diaphragm plates, different depth-span ratios and aspect ratios,so thees results have certain limitations. Based on these results,this paper analyzes the distortion effect on the simply-supported thin-walled steel box girder with the finite element model and discusses the influences of the diaphragm number and geometric parameters on distortion effect of the steel box girder.
Research conclusions:(1)The maximum normal stress of mid-span、distortion warping of the steel box girder fincreases with increase of diaphragm amount,when the box girder is narrow one with the aspect ratio of being approximately equal to 1 .5. In this case,the diaphragm plates of 3-5 ways should be installed in the span. ( 2 ) When the box girder is wide one with the aspect ratio of being approximately equal to 4. 5,the maximum normal stress of mid- span distortion warping of steel box girder decreases with increase of the diaphragmamount. In this case,the diaphragm plates of 9 ways should be installed in the span.(3)The results can provide the reference to the design of the same type bridge.
Wang Lifu, Shan Xin. Analysis of Diaphragm Setting on the Distortion of Simply Supported Steel Box Girder [J].Industrial Building , 2006 ( S) : 470-473.