The Grillage Modeling And Force Analysis Of Wide Curved Box Girder Bridge

In recent years, many high-grade highways and urban overpass were constructed. In order to satisfy the vehicle security and comfortable as far as possible, and make the drivers’visual sense and psychological reaction ability to keep the linear continuity in the plane designs of the high-grade highways, an increasing number of curved bridges were widely used. With the increase of the volume of traffic, more wide curved box girder bridges were constructed, and an increasing number of wide curved box girder bridges were researched. Relatively speaking, the wide curved box girder bridge is a complex bridge. The traditional method and model will no longer be suitable for them, and be badly in need of the new method and model to resolve the calculative problem of the wide curved box girder bridge. Base on traditional grillage method, the finite element method, and the quasi-orthotropic curved plate method, a new modeling method is presented, which is called modified grillage method of finite element model.The classified principle and method of longitudinal and transverse member is introduced about the traditional grillage method and improved grillage method, and the calculation of section characteristic value about the two different grillage method as well. Generalizing the quasi-orthotropic curved plate method from T shaped supported beam bridge to box girder bridge.Applying the FEM software of MIDAS/CIVIL, the traditional grillage method FEM model, improved grillage method FEM model and plate element FEM model for the wide curved box girder bridge the of acrylic. Through contrastive analysis of the value of end reaction, deflection and internal force for the three FEM model. Analyze the advantages and disadvantages of the improved grillage method.According to the first page wide curved box girder bridge of the A ramp of Junshan interchange bridge of the Dayue expressway from Linxiang Dajie to Yueyang of the Hangrui national expressway, which is under construction. Establishing four FEM model, including the FEM model of set horizontal and longitudinal slope, set longitudinal slope and not set horizontal slope, set horizontal slope and not set longitudinal slope, not set horizontal and longitudinal slope according to the improved grillage method. Through contrasting the four FEM model, analyzing the influence the horizontal and longitudinal slope to the wide curved box girder bridge.Through contrastive analysis of the end reaction about layout three radial bearings and four radial bearings on the first page wide curved box girder bridge of the A ramp, advising change the three radial bearings to four radial bearings, to make the use of the bearing more effective.