Cross-sectional stability of aluminium extrusions with arbitrary cross-sectional shapes - experimental and numerical research

Aluminium extrusions applied in daily practice are often thin-walled with complex cross-sectional shapes. These shapes are based on a variety of demands that are in general non-structural. As a result, several types of instability may occur, including overall and cross-sectional instability modes as well as mode interactions. Research on overall buckling is usually based on simple and symmetrical cross-sections, whereas cross-sectional instability is simplified to buckling of individual plates. It is therefore highly unlikely that these design rules provide an accurate description of the actual buckling behaviour of arbitrary cross-sections. As predicted failure modes not necessarily agree with actual ones, the outcome of the results may be overly conservative but could be unsafe as well. This article provides a summary of results and insight obtained from an extensive experimental and numerical program executed, Mennink (2002). These results shed a new light on the actual buckling behaviour of members with non-standard crosssection