Research On The Overall Stability Of Tapered Beam

As the light-weight steel structures developing rapidly,tapered beams are widely used in these structures. At present, the research of overall stability of tapered beams is very few. because of the tapered beams'cross-section changes along the direction of length, the factors that affect the overall stability of the beam more than the other,so it is of great theoretical value and practical significance to study on tapered beams. This thesis is study on the overall stability of simply supported tapered beams with monosymmetrical cross-sections un-der moment gradient.The main aspects of thesis are as follows:Firstly, summarized calculation methods of flexural-torsional buckling of the tap-ered beams,refine the calculation formulas of the cross section which considering the e-ffects of taper ratio,then analyze the errors of the cross section calculation formulas.Secondly, using the finite element program ANSYS, establish ANSYS calculation model of the tapered beams,then using the theory verify the correct and practical of the model.Thirdly,research focuses on the effect factors of tapered beam's overall stability, such as span,depth-thickness ratio of web,width- thickness ratio of flange,taper,moment gradient ratio and so on.Try to find some conclusions.Fourthly, analysis the overall stability of tapered beam with lateral bracing.Resea-rch focuses on the parameters,such as the number of lateral bracing,the spacing of lat-eral bracing and the location of lateral bracing, then obtain the variational law of over-all stability critical load,and provide some conclusions and basises can be applied to engineering design.Finally, on the basis of the above research, sum up the main conclusions and pro-pose the further improved work in this thesis according to the domestic and overseas research direction.