To provide additional insights in this matter, the hydration rate of tricalcium silicate (C 3 S) was computed by thermodynamic modelling at different hydration times (24 h, 92 h, and 463 h, equivalent to 43, 83 and 99% DoH, degree of hydration, respectively). A pure C 3 S paste was chosen as the model system considering that Moudrakovski et al. reported the DFT predicted Ca chemical shifts for this phase, which were in good agreement with the experimentally measured Ca NMR spectra of triclinic C 3 S.