Eccentric compressive performance of circular steel slag concrete-filled steel tube stub columns

Our study investigates the feasibility of using steel slag, the by-product generated during steel production, as a sustainable material in construction. Eccentric compressive tests were carried out on five sets of 10 circular steel slag concrete-filled steel tube (SSCFST) short columns, aiming to evaluate the effectiveness of using steel slag coarse aggregate in these structures. Key parameters including failure pattern, load-displacement and load-strain curves, eccentric load capacity, ductility coefficient, lateral deflection, and cross-sectional strain distribution were measured. These metrics helped in evaluating how the replacement ratio of steel slag and eccentric distance affect columns’ eccentric mechanical properties. Additionally, a refined nonlinear analytical model for these columns was developed using ABAQUS software, with its accuracy confirmed against experimental data. The study further examined the impact of multiple factors on the columns’ eccentric compressive behavior through parametric analysis. Moreover, we assessed the precision of current design approaches for estimating the eccentric compression bearing capacity of these columns. Our findings indicate that the replacement ratio of steel slag marginally affected their eccentric compressive mechanical properties, with variations under 10%. Increasing eccentricity from 0 to 0.25 and 0.5 resulted in a decrease in eccentric bearing capacity by 20.62% and 42.05%, respectively, while the ductility coefficient increased by 23.73% and 29.95%. The confinement factor and eccentric distance emerged as crucial determinants of the eccentric compressive performance. Finally, Han’s formula was found to be effective for calculating the eccentric bearing performance of circular SSCFST stub columns.