▎ 摘　　要

Graphene oxide (GO) modified cementitious materials have the potential to be increasingly applied in a range of important areas due to the enhanced microstructure, mechanical properties and durability. This work presents a thermodynamic-focused analysis of tricalcium silicate (Fe, F-C3S or Alite, simply written as C3S, the main component of ordinary Portland cement) dissolution and calcium silicate hydrate (C-S-H) precipitation rates, which were calculated from the Calcium (Ca) and Silicon (Si) element concentrations in C3S pore solutions, in the presence of GO. The solid phases of GO/C3S composites were characterised by X-ray diffraction (XRD), thermogravimetric analysis (TGA), nitrogen adsorption/desorption analysis and transmission electron microscope (TEM). The element concentrations in the pore solutions of the composites were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). Experimental results showed that, within the initial 5 min, the incorporation of 0.03 wt% GO nanosheets resulted in the increase of Si concentration by up to 14.5% while the reduction of Ca concentration by 35.3% in the pore solution, thus, changing the saturation conditions of both C3S and hydration products. After 24 h of hydration, the undersaturation of C3S increased by 2.8% when adding 0.03 wt% GO, and the C3S dissolution rate increased by up to 7.0%. Although the driving force for C-S-H precipitation was inhibited by the incorporation of GO, it was revealed that the overall C-S-H precipitation rate was enhanced throughout the 24 h of hydration. Moreover, GO was found to promote the hydration degree and hydration rate of C3S.