Performance Research For Distortional Buckling Of Cold-formed Thin-walled C-section Steel In Bending

The Cold-Formed Thin-Walled C Steel is being more and more applied to building field, because it has a large number of advantage, such as high bearing capacity,light deadweight,good economics,low labor strength of construction and so on. The factor of distortional buckling must be considered when we determine the bearing capacity of The Cold-Formed Thin-Walled C.Distortional buckling is a new kind buckling mode, which is different from local and overall buckling. The buckling mode of Cold-Formed Thin-Walled C Steel is including overall buckling,local buckling and distortional buckling.Firstly,The differential equations about distortional buckling are established according to the distortional buckling mode of cold-formed thin-walled C steel on the lateral and vertical loads. The formula of critical moment is obtained according to the differential equations of bending.Secondly, the performance of distortional buckling of Cold-Formed Thin-Walled C is research by means of test. The pure bending critical moment is analysised according to The criterion of distortional buckling. The discount coefficient is given through comparison of experiment and theory results.Thirdly, The seismic performance of Cold-Formed Thin-Walled C that critical load is distortional buckling is research by means of test. Then the experiment data was arranged and the hysteresis curve was drawn, and seismic performance is analysised.In the end, In order to improving the distortional buckling load, The measures of seting baffiles on intersecting lines are given according to the distortional buckling mode of cold-formed thin-walled C steel. Different layout ways and forms of baffiles have different effects on buckling load, which are analysised by finite element method.