Research on Distortion Effect of Thin-walled Box Girders Based on Deformation Kinematical Analysis
A theoretical analytical method was proposed to analyze the distortion effect of box girder by the corner point displacement.Drawing on the deformation kinematical analysis,the box girder deformation behavior was described and analyzed by the decomposed corner point displacements.The distribution modes of distortional warping displacement and stress ware derived using the strain assumption and the warping displacement continuity condition satisfied by the closed section.Based on the stationary principle of potential energy,the distortion governing differential equation was estab-lished with the corner point displacement as the unknown quantity.The correctness of the analytical theory and calcula-tion method was proved by numerical examples.The results show that the warping displacement analyzed by the distortion warping mode is linearly distributed along the plate width on the cross section.The distribution of warping normal stress is consistent with that obtained under the assumption of plate bending.Compared with ignoring Poisson's ratio,the in-crease of transverse bending moment after considering the influence of Poisson's ratio does not exceed 0.6％.The dis-placement of corner point in the direction of vertical top(bottom)plate is greater than that in the direction of vertical web plate.The warping normal stress and transverse bending moment at the intersection of web and top plate are less than the corresponding values at the intersection of web and bottom plate.The change of the web inclination angle has a significant impact on the warping normal stress and transverse bending moment.Reasonably reducing the inclination angle of the web can reduce the warping normal stress and transverse bending moment to a certain degree.
thin-walled box girdersdistortion effectdeformation kinematical analysiscorner displacementprinciple of stationary potential energy
万方数据
维普
