Local buckling of thin-walled polygonal columns subjected to axial compression or bending

摘要

Thin-walled polygonal section columns are a popular form of construction due mainly to aesthetic considerations.Limited literature exists,however,on the stability of the component plate elements of these columns.A finite strip model is used in this paper to investigate the local buckling behaviour and strength of these columns subject to either axial compression or unform bending.Cross-sections of square,pentagonal,hexagonal,heptagonal and octagonal profiles are considered.Elastic local buckling coefficients are presented for a veriety of plate width-to-thickness ratios.It is shown that the dimensionless buckling stress coefficident is influenced by two parameters: the nature of the applied loading and the number of sides of the section.The buckling stress coefficient is higher for bent sections than axially compressed ones,and htis difference can be quite significant.Sections with an odd number of sides have an enhanced buckling capacity over those with an even number of sides,with pentagonal sections being the strongest under axial compression or bending.