The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

10 / 2022-02-28 11:06:37

Bending Tests of Corroded RC Continuous Beams Strengthened with ICCP-SS Dual-Function Retrofitting System

Asymmetric loading,C-FRCM,Continuous beam,Corroded,ICCP-SS

This paper presents an experimental study on the flexural behavior of reinforced concrete (RC) continuous beams strengthened by carbon-fabric reinforced cementitious matrix (C-FRCM) in impressed current cathodic protection-structural strengthening (ICCP-SS) system. A total of five continuous beams were subjected to in-plane asymmetric loading. The influences of the layers of carbon fiber mesh in the C-FRCM plates and further use of U-shaped wrapping as end anchorage were carefully investigated. The failure modes, flexural bearing capacities, load-deflection curves and ductilities of the specimens were fully discussed. In addition, the influence of electrification on the fiber deterioration in C-FRCM plates under the ICCP-SS system was observed by scanning electron microscope (SEM). The complete crack development patterns, the crack widths and the deflections of the beams were obtained by digital image correlation (DIC) system, which are evaluated according to the existing concrete design criteria. The experimental results show that ICCP-SS dual-function retrofitting system can effectively improve the yield and ultimate loads of continuous beams, but there is still a debonding problem at the interface between C-FRCM and concrete. Adding U-shaped wrapping as end anchorage of C-FRCM plates can effectively avoid this problem and give full play to the reinforcing effect of C-FRCM, thus further enhance the flexural behavior of continuous beams. It is worth mentioning that the maximum crack widths of the strengthened beams are significantly lower than the calculated values, which proves that ICCP-SS dual-function retrofitting system provides good crack width control.