Experimental investigation on mechanical and water transport properties of cement composites containing graphene oxide

Recent investigations show that graphene oxide nanoparticles (GO) are promising nano-sized additives to enhance the mechanical property of cementitious materials. GO are the product of chemical exfoliation of graphite and contain a range of reactive oxygen functional groups that enable it as a suitable candidate for reaction in cementitious materials through physical functionalization. In this paper, the experimental program is performed to study the mechanical and water transport properties of GO-reinforced cement composites. Experimental results show, adding GO improved the tensile, flexural, and compressive strengths of mortar with the increase in flexural and tensile strength more than that of compressive strength. Especially, the tensile and flexural strength, when the content of GO was 0.05% bwoc, the cement mortar exhibited remarkable increase by 70% and 22% respectively, comparing with those without GO. Particularly, the compressive strength of concrete incorporating 0.1% by weight of cement GO increased by 25% and 50% than those of concrete without GO after curing for 28 days and 90 days respectively. The strengths enhancement can be attributed to the promotion of hydration and the finer pore structure of cement paste incorporating GO. There are thresholds for all mechanical strengths of cement mortar incorporating GO where the GO content exceeds the threshold, the decrease in strength is observed which can be attributed to the deformation of the hydration crystals by the change in the dosage of GO in the matrix. Penetration test results indicate that the incorporation of a very low fraction of GONPs can effectively hinder the ingress of water molecules. It can be concluded that adding GONPs improve the transport properties of concrete which subsequently improves its durability.