Bond Performance of Steel Bar in RAC under Salt-Frost and Repeated Loading

Abstract

The pullout tests are performed to investigate the bond performance of steel bar in recycled coarse aggregate concrete (RAC) under salt-frost (S-F) and repeated loading, and compared with the bond performance of steel bar in RAC under S-F and monotonic loading by the authors. The results show that the ultimate bond strength for repeated loading decreased after S-F cycles, and the ultimate bond strength for repeated loading is lower than that for monotonic loading after the same S-F cycles. The peak slip for repeated loading increased after S-F cycles, and the peak slip of the specimens for repeated loading is higher than that for monotonic loading after S-F cycles. The ultimate bond strength prediction equation of steel bar in RAC under S-F and repeated loading is presented. The S-F cycle causes the bond stress to move toward the free end, and the repeated loading accelerates the transfer of bond stress to the free end.