ABSTRACT
Carbonation is a major problem causing the durability degradation of concrete bridge structures. In this paper, 0.1%, 0.3%, and 0.5% graphene oxide (GO) were adopted to modify epoxy resin top-coat for enhancing the long-term carbonation resistance of coated concrete. After accelerated ultraviolet irradiation and subsequent carbonation experiments, the carbonation depths of coated concrete specimens were determined, and tests of scanning electron microscopy and Fourier transform infrared spectrum were also conducted on partial coating samples. Results indicated that due to the excellent barrier effect, GO can prevent the penetration of CO2 through coating, and reduce the destruction of epoxy resin function groups under ultraviolet irradiation. Hence, the carbonation resistance and the anti-aging performance of coated concrete are considerably improved. Compared with concrete with blank coating, 0.3% GO can increase the carbonation resistance by 37.3% and decrease the aging rate by 40.1% for concrete with a GO modified top-coat.
