Buckling Analysis of Double-Limb Lipped Channel Section Member under Axial Load

Abstract

Double-limb lipped channel section steel member is formed by connecting two single limb members with bolts in order to improve the buckling performance. In order to research the buckling form and ultimate bearing capacity of members with different slenderness ratios under axial load, nonlinear analysis of buckling performance is done to this kind of section using the finite element analysis software ANSYS. The influence on bearing capacity caused by height-breadth ratio of section, height-thickness ratio of web and breadth-thickness ratio of flange is analyzed. The results show that: (1) for larger slenderness ratio, complete buckling occurs to the column mainly and the slenderness ratio has larger influence on buckling bearing capacity, while for smaller slenderness ratio, local distortional buckling occurs more; (2) in a certain range, the increase of height-breadth ratio could raise the ultimate bearing capacity of member, but excessive height-breadth ratio would make the ultimate bearing capacity decrease, (3) the increase of both height-thickness ratio and breadth-thickness ratio would decrease the ultimate bearing capacity.