Experimental Study on Long‐Term Performance of Postinstalled Reinforcing Bars

ABSTRACT Postinstalled reinforcing bars play a crucial role in maintaining, extending the service life, and enhancing the seismic capacity of existing concrete structures. The displacement‐time distribution under sustained loading for 90 days was established through long‐term performance testing. As a result, a long‐term slip calculation formula was derived, and a 50‐year slip prediction method for postinstalled reinforcing bars was developed. Additionally, a comparative analysis of the pullout damage between postinstalled reinforcing bars and benchmark specimens after long‐term loading was conducted to evaluate embedment performance, including stiffness degradation and residual capacity loss due to creep. A comprehensive methodology for the long‐term performance inspection and testing of postinstalled reinforcing bar systems is also proposed for engineering evaluations.