Experimental investigation on sea sand concrete-filled stainless steel tubular stub columns

Abstract

This paper studies the behaviour of sea sand concrete-filled stainless steel tube (CFSST) stub columns under axial compression through experimental investigations. A total of 48 specimens were tested, including circular and square stainless steel tubes filled with three types of core concrete, including natural river sand concrete, desalted sea sand concrete and natural sea sand concrete. The effects of key parameters such as the tubular thickness of stainless steel, the cross-sectional configuration and the types of concrete infill on the behaviour of these innovative composite columns were investigated. The confinement effects of CFSST with sea sand concrete were evaluated and compared with that of CFSST with conventional river sand concrete. Testing results showed that the tested CFSST columns showed generally high strength and excellent ductility, while the confinement effect of stainless steel on the sea sand concrete is as reliable as that on the river sand concrete counterpart. Comparisons were made between the test results and the predicted ultimate sectional capacity using the existing specifications AISC360–10 (2010), EC4 (2004) and DBJ/T13-51-2010 (2010). These codes are proved reasonably conservative for predicting the sectional strength of sea sand concrete-filled stainless steel tubular stub columns.