ABSTRACT
When members of steel structures are subjected to an earthquake motion, global and local buckling can lead to localized plastic strain and subsequent ductile fracture, which has been observed in past strong earthquakes. Therefore, it is of significant importance to predict ductile crack initiation and propagation of steel members, which can be employed to evaluate ductility and energy dissipation capacity of structural steel members and whole structures. The aim of this paper is to investigate post-buckling cracking mode and energy dissipation capacity of cold-formed Square Hollow Section (SHS) stub columns. The effects of width-to-thickness ratio and heat treatment are experimentally studied through six specimens under incremental loading. Ductile fracture was identified in the experiments. Locations of crack initiation were different for specimens with and without heat treatment. The total plastic energy dissipation capacity generally decreases as the width-to-thickness ratio increases.
