Research On The Load Capacity Of Cold-formed Steel Coupled Built-up Box Beam Under Pure Bending On The Web

This paper mainly describes the detailed study resulted on flexural capacity ofcold-formed steel built-up box girder by numerical analysis, and the corresponding proposeddesign method is proposed.At first, cold-formed steel built-up box girders were modelled using the finite elementanalysis software ANSYS (version10) involving geometric largedeformation, materialsnonlinear and contact problemto simulate the tests conducted by Beshara.The finite elementmodel involving geometric large deformation, materials nonlinear and contact problem.Fromthe comparison of computer analysis with experimental results, the finite element model isproved to be accurate. providing an actual gist for the research of flexural capacity ofcold-formed steel built-up box girder.Secondly, the parametric study analysis was carried out to mainly determine the effect ofthe spacing of screw, height to width ratio, width to thickness ratio and material yield stress.The results of the study indicate that the flexural capacity of cold-formed steel built-up boxgirder increases when the material yield stress, height to width ratio and width to thicknessratio increased.The spacing of screw suggestions for150mm, can ensure the wholecollaborative work performance of the cold-formed steel built-up box girder.Subsequently, the flexural capacity of cold-formed steel built-up box girder are caculatedby the GB500182002, AISI2004("Effective Width Method").Then the results calculated byspecification are compared with the ANSYS results.The comparisons show that the results byspecification is conservative.The ANSYS results to the results calculated by specificationratio decreases when the material yield stress, height to width ratio and width to thicknessratio increased.so specification calculation shall not apply to the cold-formed steel built-upbox girder which plate’s width to thickness ratio are too big, and steel yield strength is high,the greater the size of the limit.Finally, based on the nonlinear finite element analysis, the simple corresponding designmethod are proposed.