Research On The Practical Calculation Method For Multi Room Of Broad Box Girder

The economic development drives to traffic modernization, the transverse width ofthe bridge is continuously increasing. In this case, some construction of prestressedconcrete beam bridges are built at home and abroad, widespread use of the sections islarge cantilever and single box multi cell of broad box girder, especially the8lanehighway bridge in the city. This kind of bridge has many characteristics, such as theweb of large distance, transverse flange wide and box with thin wall. In structuraldesign of this bridge, the performance and features of stress in thin-walled structure aremore prominent. The section of structure not only produces the shearing force, but alsogenerates torsion warping, distortion and other effects. The existing girder theory cannotbe applied in the multi cell wide box beam, because of its specificity. So it is necessaryto explore and research further the girder theory.The article is based on the grillage method. The flexible shear grillage model andsolid element model are analyzed by the finite element software. The grillage methodhas some limitations in solving stress problem of broad box girder. The article tries toexplore a practical calculation method by using the orthotropic plate method to modifygrillage model stiffness and calculating an improved spatial grillage model.The article focuses primary results on calculating method of single box multi cellof broad box girder problem. The improved spatial grillage method has a better practicalapplication value and provides a basis for further research.