腹板开孔冷弯薄壁槽钢偏压构件畸变屈曲试验与设计方法OA

To investigate the distortional buckling performance and design methods for the bearing capacity of cold-formed thin-walled channel steel members with web openings under eccentric compression,this study analyzes the failure mechanisms and bearing capacities of members with different opening shapes,slenderness ratios,and eccen-tricity ratios through combined testing and finite element simulation.Eccentric compression tests revealed that web openings significantly reduce the member's ultimate bearing capacity,with rectangular holes causing a more pronounced reduction than circular holes.Short columns primarily failed through distortional buckling,while long columns exhibited a coupled failure mode of distortion and global buckling.A numerical model developed using the finite element software ABAQUS showed good agreement with the experimental results,verifying the reliability of the finite element method.Further finite element analysis demonstrated that the ultimate bearing capacity decreases with increasing eccentricity.Furthermore,larger width-thickness ratios and hole-height ratios resulted in lower ultimate bearing capacities.Finally,a comparison of the ultimate bearing capacities from tests,finite element anal-ysis,and the direct strength method calculation showed that the direct strength method provides a safe estimate for the buckling capacity of such members.Therefore,it can be reliably used to calculate the distortional buckling bearing capacity of cold-formed thin-walled channel steel members with web openings.