Impedance Monitoring at Tendon-Anchorage via Mountable PZT Interface and Temperature-Effect Compensation

In this study, the prestress force in prestressed concrete ( PSC) girders is monitored via mountable PZT interface under varying temperature. Firstly, an impedance-based technique using mountable PZT interface is proposed for prestress-loss monitoring in tendon-anchorage systems. A cross correlation-based temperature-effect compensation algorithm using an effective frequency shift ( EFS) of impedance signatures is visited. Secondly, lab-scale experiments are performed on a PSC girder instrumented with a mountable PZT interface at tendon-anchorage. A series of temperature variation and prestress-loss events are simulated for the lab-scale PSC girder. Thirdly, the feasibility of the mountable PZT interface for prestress-loss monitoring in tendon-anchorage is experimentally verified under constant temperature conditions. Finally, the PZT interface device is examined for prestress-loss monitoring under temperature changes to validate its applicability. The temperature effect on impedance signatures is compensated by minimizing cross-correlation deviation between impedance patterns of the mountable PZT interface.