| The prestressed concrete composite box girder with corrugated steel webs, a new type of bridge structure, are webs of concrete instead of corrugated steel webs, and adopt the Box External prestressed force technology, which lighten the main beam. With Chongqing a PC composite box girder with corrugated steel webs as example, adopting finite element program ANSYS to construct space finite element model, this paper conducts the linear and nonlinear finite element analysis to corrugated steel webs'geometrical parameter which affect mechanical properties of corrugated steel webs PC's composite box girder, and finally the reference index of corrugated steel web size is generated. The main work includes the following aspects:1.Construct the composite box girder of corrugated steel webs, and verify the two important assumptions on it:(1)Moment is only resisted by the cross formed by concrete roof and floor, if corrugated steel webs'function of antibanding longitudinally is neglected.(2) Shearing force is completely born by corrugated steel webs and distribute averagely on it.2.Analyze the corrugation configuration (length of horizontal panel, the configuration angle) and the influence of the change of plate steel thickness to section stress under the force of symmetrical and eccentric load during elastic stage. The results showed that:(1)There is little influence of Corrugated steel webs'geometrical parameter to the girder's deflection.(2) It is favorable to reduce the horizontal panel length of corrugated steel webs no matter symmetrical load or eccentric loads, as it can improve its mechanical properties.(3) Mechanical properties of the structure can be increased significantly by improved the configuration angle.(4)The ratio between maximum thickness of the floor and roof of corrugated steel webs'thickness should take about 20.3.The thesis also studies elastic theoretical formula of local, overall and composite buckling of corrugated steel webs at home and in aboard, and the stress experimental formula of local and overall buckling within plastic effect's inelastic range are taken into consideration.4.This thesis takes Construction's initial geometry defects into consideration, which are computed into the effect to material nonlinearity and geometric nonlinearity.The author compares and analyzes its corrugation configuration (horizontal panel length,the configuration angle) and the influence of the change of steel's thickness to corrugated steel webs'shearing buckling stress and buckling model. The results showed that:(1)It is an effective measure of increasing the thickness of the corrugated webs to improve the shear strength.(2)There is little influence of the change of horizontal panel length to limit buckling stress of corrugated steel webs, but in order to prevent the occurrence of local buckling failure, the length of horizontal panel should be not more than 450mm.(3)The buckling strength can be increased the significantly by increase configuration angle.
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