Abstract:

The uniaxial eccentric compressive experiments of nine rectangular concrete-filled steel tubular stub columns, seven with and two without binding bars, were carried out. The effects of the eccentricity ratio and the horizontal spacing of the binding bars on the eccentric compressive behaviors of the columns were also analyzed. The results indicate that （ 1 ） the setting of binding bars improves the ductility of the columns and delays the local buck- ling of steel tubes; （2） the eccentric bearing strength of the columns decreases with the increase in eccentricity ratio ; and （3） the ductility of the columns with the same eccentricity ratio increases with the decrease in binding bar spacing. Moreover, the numerical results of bearing strength accord well with the experimental ones, while the resuits obtained based on the domestic design codes are much lower than the experimental ones.

Key words: rectangular concrete-filled steel tube column, binding bar, eccentric compressive behavior, ductility, bearing strength, constitutive relationship