Numerical Slenderness Approach for design of complex aluminum extrusions subjected to flexural loading

Aluminum structural members can be extruded to various cross-sectional shapes, including additional elements projecting out of flat flanges or webs. The additional elements contribute to flexural strength increase due to local buckling strength increase. In this study, a general design approach is developed for complex extrusions, accounting for the local buckling strength increase. This approach uses numerical buckling analyses, while the overall framework of the existing specification provisions is maintained. The approach is evaluated through parametric studies of seven different kinds of cross-sections, using finite element analysis. The FEA models and the parametric study results are validated through physical tests.