EMI-based interfacial damage evolution of CFRP plates-strengthened RC beams under low-cycle fatigue loading and wetting/drying cycles. (1st March 2023)

• Record Type: Journal Article
• Authors: Li, Xiaoda; Zhu, Miaochang; Liu, Zongchao; Deng, Jun
• Is Part Of: Composite structures. Volume 307(2023)
• Publication Date: 2023-03-01
• Subjects: CFRP-strengthened RC beam -- Low-cycle fatigue loading -- Wetting/drying cycles -- EMI method -- Interfacial deterioration; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2022.116653
• Languages: English
• ISSNs: 0263-8223

Abstract

Highlights: A novel technique was proposed to monitor the interfacial damage of composite structure. EMI method can well reveal the interfacial deterioration under LCF and WDCs. The correlation between the RMSD and the mechanical properties can be well established. Abstract: The bonding interface of carbon fiber reinforced polymer (CFRP) strengthened reinforced concrete (RC) beams can deteriorate under low-cycle fatigue (LCF) or wetting/drying cycles (WDCs). Besides, their combined effect can aggravate the degradation of the bonding interface, but the research is limited. This paper aims to investigate the combined effects of LCF and WDC on the interfacial damage evolution of CFRP-strengthened RC beams through the electromechanical impedance (EMI) method based on piezoelectric ceramics (PZTs). The strengthened beams were first subjected to LCF and then exposed to WDCs; afterward, the four-point bending test was conducted. The results show that the EMI method could clearly and sensitively capture the crack initiation, interfacial damage development, and debonding process of the strengthened beams during the LCF and four-point bending procedure. Moreover, the EMI monitoring results demonstrated that both LCF and WDC exposure deteriorated interfacial bonding, and the combined actions contributed to significant degradation. In addition, the peak root mean square deviation (RMSD) at the CFRP mid-span and plate end could prominently reflect the degradation of interfacial performance. Thus, a close correlation was theoretically established between the PZT monitoring results and mechanical properties LCF of the CFRP-strengthened RC beams.