Static and Cyclic Flexural Behaviors of Edge-Oxidized Graphene Oxide Cement Composites

This paper investigates the flexural fatigue behavior of cement mortar mixed with edge-oxidized graphene oxide (EOGO), a carbon nanomaterial reinforcing cement hydration products. EOGO is produced by a mechanochemical process that enables dramatically reduced costs, making it suitable for large-volume infrastructure construction. The compressive and flexural strengths of the EOGO cement mortar mixtures are also compared with the results of fatigue tests. Test results indicate that the cement mortar containing 0.05% of EOGO by weight of cement exhibits the best flexural fatigue performance as well as compressive and flexural strengths. It is also found that the EOGO mixed specimens show a faster increase in flexural fatigue strains than the control specimens under sinusoidal loading. This implies that EOGO helps to prevent or delay the propagation of internal damage (e.g., microcracks) in the cement composites in an early fatigue phase, resulting in enhanced flexural ductility. Thus, it is concluded that the EOGO can be used as an additive, with cost competitiveness, for improving the structural fatigue performance of cementitious composites. (C) 2019 American Society of Civil Engineers.