Numerical analysis of stainless steel I‐section columns with sinusoidal web openings

Abstract

The structural response of welded stainless steel I‐sections with large web openings under compression remains largely unexplored, despite its importance for understanding the behaviour of perforated members in bending or combined compression plus bending. This study presents a numerical investigation of welded stainless steel I‐section stub columns with closely spaced sinusoidal web openings, considering conventional austenitic materials as well as duplex and hybrid austenitic–duplex configurations. The influence of flange–web slenderness interaction and material distribution on instability mechanisms and cross‐sectional resistance is examined. The results reveal two distinct instability behaviours governed by the relative flange and web slenderness. Material distribution primarily affects resistance through the flanges and hybrid configurations with duplex flanges achieve increases of up to 70% relative to fully austenitic sections.