Study on the bond-slip properties and constitutive relationships of steel reinforced concrete column under eccentric compression

The study of bond-slip properties, which are greatly influenced by the stress distributions between the shaped steel and the concrete,is very important in the research field of steel reinforced concrete (SRC) structures. Taking the parameters of load eccentricity e(0)/h, slenderness ratio l(0)/h as variables, bond-slip tests are carried out on 20 SRC eccentrically compressive columns. The distribution regulars of the interior bond stress and the slip along the anchorage length are investigated. The result indicates that as the load eccentricity and the slenderness ratio of the specimens increase, the relative slip between the shaped steel and the concrete increases,while the decrease in the slenderness ratio and the increase in load eccentricity lead to the increase in bond strength to some extent. The calculation formulae for the characteristic values in the bond-slip curve are obtained in terms of the statistical regression. The bond-slip constitutive equations for SRC eccentrically compressive column are proposed as well. It is expected that the present work can be helpful for the finite element analysis and load-bearing capacity calculation of SRC eccentrically compressive column taking account of the bond-slip effect.