Advanced Analysis of Beam-columns Resisting Minor Axis Bending

Beam-columns are structural members in buildings that resist both compression and flexure. Current methods for designing beam-columns include the effective length method (ELM) and the direct analysis method (DM), which both require the use of the length of the member in design equations. However, there exist structural systems, such as an arch-type structure, where member lengths are difficult to define. In 2016, the American Institute of Steel Construction (AISC) proposed an alternative design method, Design by Advanced Elastic Analysis method (DMMI), to further simplify the current design process. This research provides data for further assessment of AISC’s new provisions, with a focus on beam-columns subjected to minor-axis bending. This study required the computational modeling and analysis of beam-columns with various cross-sections and slenderness ratios. Through the employment of finite element analysis software and development of MATLAB-based programs, it was possible to investigate beam-columns using the conventional and the relatively new method. By changing the demand-to-capacity ratio of axial force and bending, design curves for beam-columns of different methods were plotted and the percent errors were calculated for a wide range of member slenderness ratios and cross-section profiles. In observing results for W-section and HSS-section members, this new design method provides similar results to the more established methods. The results of this research project provide suggestions for future editions of AISC’s Specification for Structural Steel Buildings