Cross-section classification for cold-formed and built-up high strength carbon and stainless steel tubes under compression

• High strength (HS) carbon and stainless steel tubes have been investigated
• 147 stub column experimental results on HS tubes were analysed
• 46 numerical data on HS stainless steel tubes were obtained
• Slenderness limits on EC3, AISC/ASCE, AS/NSZ can be adopted for HS RHS
• New slenderness limits and parameters based on EC3 are proposed

This paper presents an assessment on the current yield slenderness limits under axial compression for cold-formed and built-up high strength carbon and stainless steel hollow sections. The definition of high strength steel in this paper refers to the materials with nominal yield strength or 0.2% proof stress which is greater than 700 MPa (Eurocode 3: Part 1-12) for carbon steel and greater than 480 MPa (Eurocode 3: Part 1-4) for stainless steel. A total of 147 stub column experimental results was compiled and assessed. Companion 46 finite element simulations were performed in this study and the results concurred with the experimental observations. The structural performance data showed that the current slenderness limits adopted in Eurocode 3, American and Australian Standards for both carbon and stainless steel under axial compression can be safely adopted for the high strength steel counterparts. New slenderness parameters and limits were also proposed to improve the design efficiency.