The role of graphene oxide on the hydration process and chemical shrinkage of cement composites

Graphene oxide (GO) has attracted increasing attention for its application in cementitious materials as it can be used to regulate the hydration products of cement and improve the properties of cement composites. This paper investigated the role of GO on the hydration process and chemical shrinkage of a cement paste through an experimental study and molecular dynamics simulation. The hydration heat flow of a cement composite with GO (CCG) was characterised by using an isothermal calorimeter. The chemical shrinkage of the CCG was also measured by applying a modified method based on ASTM C1608. The test results have shown that incorporating GO can mainly accelerate the hydration rate of cement composites at the early stage, but would not change the four-stage process of the cement hydration. The addition of GO by 0.3 wt. % of cement is able to reduce the chemical shrinkage of the cement composites. This regulation effect is mainly attributed to the hydrogen bonding, which has been verified by the molecular dynamics simulation.