Research On The Overall Buckling Behavior Of Cold-formed Thin-walled Steel Columns Of Specially-shaped Section Under Axial Compression

This article researchs on the cold-formed thin-walled steel columns of specially-shaped section under axial compression, After the molding process of cold bending and welding,it has many outstanding characteristics,such as the reasonable material distribution,the high utilization of steel,the better mechanical properties,etc.,It has a high strength to weight.However,there are no specific national codes for this cold-formed thin-walled steel columns of specially-shaped section under axial compression.Therefore,It is necessary to do more research on the overall buckling behavior, in order to determined the design method, and the result provides a reliable basis for the engineering projects.By the way of experimental analysis and numerical analysis,researching the overall buckling behavior of cold-formed thin-walled steel columns of specially-shaped section under axial compression. Giving the important characteristic parameters of strength and deformation by material stretching test of slice. Considering the effect of cold work and welding,test the important characteristic parameters of strength and deformation by material stretching test of corner piece; Giving the ultimate-bearing capacity and the yield strength of total cross section by short column test under axial compression; Giving the ultimate-bearing capacity by axial-compressed long columns test;ANSYS can analyse member’s performance under axial compression and fit the test results,Providing more experimental data for further research,and contrast the result of the finite element analysis with the column curves. Based on the result of analysis,this can be summarized as follows:(1) Considering the effect of cold bending and welding,the yield strength of total cross section greatly improved,the compression column’s ultimate load can be Calculated according the design method in the "Technical Code of Cold-formed Thin-wall Steel Structures".(2) The ultimate-bearing capacity can be Calculated according the design method in the "Code for Design of Steel Structures".(3) The test result show that local buckling and torsional buckling didn’t takes place under Axial Compression,and the ultimate failure mode is overall bending failure.(4) Regardless of whether you bored on the column or not, there is no impacted on the the overall buckling behavior of cold-formed thin-walled steel columns of specially-shaped section under axial compression.