Interfacial properties and bond strength model of TRC-confined concrete and deformed reinforcement under corrosion

Abstract

ABSTRACTThe interfacial bonding behavior of textile reinforced concrete (TRC)-confined concrete and corroded steel bars was studied by central pull-out testing using three types of specimens (not strengthened, strengthened after corrosion and strengthened before corrosion). The results show that without the TRC constraint, the ultimate bond strength between the concrete and corroded steel bar decreases with increasing corrosion ratio, especially after the concrete cracks due to reinforcement corrosion, at which point the ultimate bond strength rapidly decreases. However, the ultimate bond strength of the specimens strengthened after corrosion can be three times greater than the strength of the specimens not strengthened when the concrete cracks due to reinforcement corrosion. For the specimens strengthened before corrosion, the TRC strengthening layer effectively limits the decrease in the ultimate bond strength between the corroded steel bars and concrete, which results in specimens with a high interfacial bond strength at high corrosion ratios. Thus, compared to the other two types of specimens, this case comparatively yielded the best results. Finally, for all three types of specimens and according to the experimental data, a calculation model of the ultimate bond strength was established considering changes in the corrosion ratio.