Regulation mechanism of graphene oxide on creep of cement-based composites

In order to explore the creep regulation mechanism of graphene oxide (GO) on cement-based composites, the creep of cement mortar with different GO contents was tested by using creep loading frame. Starting from the hydration and microstructure of cement-based composites, the effect of GO on the creep of cement mortar was studied by SEM, XRD and FTIR, and the regulation mechanism was explained. The results show that GO can regulate the shape and aggregation state of hydration products of cement-based composites and reduce macro creep. When the content (mass ratio to cement) of GO is greater than 0.02%, the creep of cement mortar is greatly reduced. The addition of GO promotes the adsorption and diffusion of water molecules by hydrated calcium silicate (CSH), increases the internal CSH content and makes the structure of hydration products more compact. The hydrogen bond formed by GO and CSH can enhance the bonding force between the two and enhance the adsorption of water molecules between the CSH-GO layers, thus realizing the regulation of creep of cement mortar. The results have important theoretical value for the design of cement-based composites according to end use, and are expected to be applied in prestressed concrete structures.