Experimental test and analytical modeling of mechanical properties of graphene-oxide cement composites

Graphene oxide has recently been considered as an ideal candidate for enhancing the mechanical properties of the cement due to its good dispersion property and high surface area. Much of work has been done on experimentally investigating the mechanical properties of graphene oxide-cementitious composites; but there are currently no models for accurate estimation of their mechanical properties, making proper analysis and design of graphene oxide-cement-based materials a major challenge. This paper attempts to develop a novel multi-scale analytical model for predicting the elastic modulus of graphene oxide-cement taking into account the graphene oxide/cement ratio, porosity and mechanical properties of different phases. This model employs Eshelby tensor and Mori-Tanaka solution in the process of upscaling the elastic properties of graphene oxide-cement through different length scales. In-situ micro-bending tests were conducted to elucidate the behaviour of the graphene oxide-cement composites and verify the proposed model. The obtained results showed that the addition of graphene oxide can change the morphology and enhance the mechanical properties of the cement. The developed model can be used as a tool to determine the elastic properties of graphene oxide-cement through different length scales.