Impacts of geometric imperfections on global buckling behaviors of cold-rolled aluminium alloy channel beams

Abstract

Aluminium alloy structures have been seen as relatively new structures and have illustrated their advantages based on their properties of excellent corrosion resistance and lightweight. Aluminium alloy members can be manufactured by two methods including extrusion and cold-forming. While extrusion is seen as the traditional method worldwide, cold-rolling is recently applied to successfully produce cold-rolled aluminium sections with advantages in cost-effectiveness compared to extruded sections. significant geometric imperfections are found to be contained in these aluminium sections, which affects the strengths and behaviors of these section members. The consideration of geometric imperfections in the buckling analyses allows for determining the detrimental cases of buckling behaviors under load actions; that can be used for the proposal in design for further studies. The paper, therefore, studies the impacts of geometric imperfections on the global strengths and behaviors of such aluminium alloy beams; this will be the base for the development of parametric studies to obtain numerical data for design proposals. The imperfection values for the investigations are taken as random samples generated based on the collected imperfection data in previous studies. Also, a coefficient is proposed in reliability analysis to consider the influences of global imperfections on the global buckling moments of cold-rolled aluminium channel beams using the probability-based load and resistance factor design (LRFD) method as regulated in the American Aluminum Specification.