Local buckling of aluminium channels under uniform compression: Theoretical analysis and experimental tests

The aim of the work is the evaluation of the ultimate behaviour of aluminium channel sections subjected to local buckling under uniform compression. In particular, two different approaches are presented to predict the inelastic response of aluminium members: the Deformation Theory of Plasticity (DTP) and the Effective Thickness Method (ETM). The first one represents a theoretical procedure applied according to elastic-plastic stability theory of a single plate and considering restraining effects of adjacent plate elements. The Effective Thickness Method (ETM) is a simplified approach currently adopted by Eurocode 9 to estimate the ultimate resistance of aluminium sections taking into account the local buckling effects. In this paper, an extension of this approach is provided by introducing the mechanical non-linearity of material and the influence of section plates constraints.Finally, the accuracy of these procedures is demonstrated by comparing the ultimate compressive resistance derived by theoretical approaches with the values of the ultimate loads provided by the stub column tests performed at the University of Salerno.