Compensation of Temperature Effect on Impedance-based Damage Monitoring in Prestressed Tendon-Anchorage System
Jeong-Tae Kim1, Thanh-Canh Huynh1, So-Young Lee1, Joo-Young Ryu1
1 Pukyong National University
45 Yongso-ro, Nam-gu, Busan, Korea
idis@pknu.ac.kr
ce.huynh@gmail.com
cozy1028@nate.com
soyounglee.amy@gmail.com
Abstract. In this study, two well-known algorithms of temperature-effect compensation are examined for electromechanical (EM) impedance monitoring at tendon-anchorage of prestressed structures. Firstly, the EM impedance monitoring of prestressed tendon-anchorages using the mountable interface technique is visited. Secondly, two well-known algorithms of temperature compensation, including the principle component analysis (PCA) and the effective frequency shift (EFS) are selected for the impedance-based damage diagnosis in tendon-anchorage under temperature variation. Thirdly, impedance measurements are conducted at tendon-anchorage of a lab-scale prestressed concrete (PSC) girder for which a series of temperature variation and prestress-loss events are simulated. Finally, the selected temperature-compensation algorithms are employed to adjust the temperature effects on the measured impedance responses.
Keywords: electromechanical impedance, prestress-loss, temperature compensation, PCA, EFS.
