Study on the bond-slip behavior between steel bar and rammed earth

Abstract

The steel bars significantly enhance the mechanical properties of rammed earth, as they together withstand external loads. In order to investigate the bond performance between steel bars and rammed earth, the pull-out tests were conducted on 60 specimens. This study investigated the distribution of bond stress along the anchorage length of steel bars by embedding strain gauges inside the bars. The effects of four types of anchorage length, three types of cover thickness, three types of steel bar diameter and three types of compressive strength of rammed earth on the bond-slip behavior were investigated. Through experimental research and theoretical analysis, the distribution law of the bond stress along the anchorage length was obtained. The transfer mechanism of the bond stress and the failure mode of the specimens were analyzed. An improved bond-slip constitutive model was proposed to reflect the influence of the position function of bond stress distribution. Furthermore, a theoretical formula for the bond strength was proposed based on the analytical approach of elastic solid mechanics and the failure modes of the specimens, and its accuracy was validated by experimental results.