Graphene Oxide as Additive to Replace Using Air-Entraining Agents

Despite its negative impact on compressive strength of concrete, practitioners rely exclusively on using air entrainment to defeat freezing-and-thawing deterioration. This paper describes the use of graphene oxide (GO) as an effective method to minimize the negative impact of freezing-and-thawing action in concrete while maintaining high compressive strength. Two series of graphene oxide-bearing concrete samples (containing 0.01% and 0.06% graphene oxide by cement weight) were produced. Plain concrete samples and samples with 4% air-entraining content were also produced for comparison. All the concrete samples were subjected to up to 500 repeated freezing-and-thawing cycles. Different series of tests such as electric resistance, nitrogen adsorption, and compressive strength were conducted within and at the end of the freezing-and-thawing cycles. The results show that the GO specimens indicate higher initial compressive strength than the control and the air-entrained specimens. A significant enhancement of freezing-and-thawing resistance in the graphene oxide-bearing concrete samples was expressed in maintaining the compressive strength close to initial values before the exposure to freezing-and-thawing cycles. Keywords: air content; freezing and thawing; graphene oxide; microcrack; nitrogen adsorption.