Workability, microstructure, strength properties and durability properties of graphene oxide reinforced cement paste

Graphene oxide (GO) is one of the prominent nanomaterial, this has been utilised in the cement composite materials. Graphene oxide represents unprecedented range of properties with a potential to enhance the strength and toughness of cement-based composites. In this study, the influence of graphene oxide was evaluated on the workability, microstructure, strength and durability properties of the fresh and hardened cement composites. Different percentages of graphene oxide were added at 0wt%, 0.01wt%, 0.02wt%, 0.03wt% and 0.04wt% by weight of cement. Workability in terms of fluidity, setting time and viscosity tests were conducted to the fresh GO-cement paste samples. Compressive and flexural strength tests were conducted to the hardened GO-cement paste samples at 28 days. Through scanning electron microscopy (SEM), morphology and microstructure of hardened cement paste were investigated and XRD technique was assisted in identifying the crystalline materials and studying the phase composition of cement composites. Results exhibited that, graphene oxide addition increases the viscosity, decreases the fluidity and shortens the setting time of the cement paste. Increased compressive and flexural strength results were appeared due to the addition of graphene oxide at different dosages. At 0.04wt% of graphene oxide dosage, the compressive strength was increased by 46.6% and flexural strength was increased by 75% than normal cement paste at 28 days. Water permeability of the cement composite specimens was highly reduced due to the graphene oxide reinforced infiltration barrier, which leads to the improvement in durability.