Effect of low-level cyclic loading on bond behavior of a steel bar in concrete with pre-existing damage

Understanding the bond behavior of steel rebar in concrete is important in order to determine the performance of a reinforced concrete structure. Although numerous studies have been carried out by many researchers to develop a robust model for numerical analysis, no consensus has been reached as the bond behavior depends on hysteresis. In this study, the bond behavior of a steel bar in concrete with pre-existing damage is investigated under low-level cyclic loading. Based on the experimental bond stress and slip curve, a numerical model for finite element analysis to simulate the effect of low-level cyclic loading is proposed. The results from the numerical analysis show good agreement with the experimental data, including accumulated damage on stiffness and strength throughout entire load cycles.