Study on concrete-filled stainless steel–carbon steel tubular (CFSCT) stub columns under compression

A concrete-filled stainless steel–carbon steel tubular (CFSCT) column is introduced as a new form of composite member in this paper, which is believed to achieve higher corrosion resistance, higher bearing capacity and lower cost by combination the advantages of stainless steel and concrete filled steel tube (CFST) structure. A series of compression test was carried out on this newly proposed composite column. A modified stress–strain model for concrete core was proposed and then three-dimensional nonlinear finite-element (FE) models were established and verified with the experimental results. Close agreement was achieved between the test and numerical results in terms of load–deformation responses. A parametric study, including tube thickness, diameter and yield strength of carbon steel tube was also conducted to give a clear insight on the performance such composite columns.

► A newly proposed composite column was first tested in this paper.
► A modified stress–strain model was proposed for concrete confined by double steel tubes.
► The amount of stainless steel in the column was analyzed.