Study On Local-distortional Interactive Buckling Mechanical Properties Of High Strength Cold-formed Thin-walled Steel Columns With Holes

With the rapid and high-quality development of the construction industry,cold-formed thin-walled steel has been widely used in practical engineering.With the increasingly rich and complex application scenarios,the requirements for the stability of cold-formed thin-walled steel members are becoming more and more strict.In practical engineering applications,it is often necessary to open holes in cold-formed thin-walled steel members to facilitate the passage of lines and pipes.The opening of holes and the change of hole diameter will affect the bearing capacity and buckling failure mode of members.At present,there are relatively few studies on the axial compressive stability of high-strength v-stiffened cold-formed thin-walled steel columns with perforated webs.The development of relevant research is of great significance to establish a perfect theoretical system and guide engineering practice.Therefore,this paper selects web v-stiffened high-strength cold-formed thin-walled steel members with local distortion related buckling as the research object to study and analyze the effects of section size parameters and holes on the bearing capacity and buckling failure mode of members.In this paper,the buckling failure modes and related mechanical properties of members with different sections are studied by using finite element numerical simulation software.It is found that the ultimate bearing capacity of members is negatively correlated with the length of members.Most of the buckling failure modes of short columns are asymmetric I-I local distortion coupled buckling,while longer columns will have wavy local distortion related buckling.In the component parameters,the increase of web width and flange width has a small strengthening effect on the bearing capacity of the component;The increase of thickNess will greatly strengthen the bearing capacity and deformation resistance of members.The effects of the existence of holes and the change of pore size on the stability of members are further studied.Generally speaking,the increase of aperture will weaken the bearing capacity of members,but when the change of aperture has an impact on the buckling failure mode of members,the phenomenon of increasing aperture and increasing bearing capacity may occur.At the same time,the deformation capacity of the member decreases with the increase of the aperture.Based on the numerical simulation results and combined with the existing calculation methods of axial compression capacity of cold-formed thin-walled steel members by scholars at home and abroad,a formula for calculating the bearing capacity of cold-formed thin-walled steel columns with perforated web v-stiffeners under local distortion dependent buckling is proposed.The results of the proposed calculation method are compared with the finite element simulation results,and the difference is small,so as to verify the reliability of the proposed calculation method.Figure[34]table[19]reference[43]...