Behaviour of slender square concrete-filled stainless steel columns subject to axial load

Due to its excellent corrosion resistance, decorative qualities, ease of maintenance and fire resistance, the past few decades have seen the accelerating interest in the use of stainless steel in construction throughout the world. Concrete-filled steel tubular columns comprised of stainless steel ideally combines the advantages of both stainless steel and concrete. So far, research on the concrete-filled stainless steel tubular (CFSST) columns is still quite limited, and mainly focused on short columns. In practice, columns are usually subjected to the influence of slenderness. A total of 6 square CFSST columns were tested under axial loading conditions to evaluate the influence of global slenderness. Several existing design codes, including the Australian design code AS 5100 (2004), American code AISC (2005), Chinese code DBJ 13-51-2003 (2003) and Eurocode 4 (2004), are used to predict the column strength and are compared with the test results. This is helpful in evaluating the applicability of the current codes in calculating the strength of slender CFSST columns.