Application of thermodynamic modelling to hydrated cements

Thermodynamic modelling is essential to understand the effect of binder composition on hydrate assemblage in modern Portland composite cements and its effect on durability. Binary and ternary plots of the hydrates' volumes can visualize the effect of different SCMs at different hydration times. The pore solution data analysis and the derived saturation indices can be used to gain further insights into the processes governing the dissolution and precipitation of hydrates. The modelling of the hydrated cements exposed to different environments has contributed significantly to the understanding of the determining factors governing sulfate, chloride and carbonate attack. Thermodynamics models and modelling approaches have achieved a mature level. In the last years, more thermodynamic data have become available making thermodynamic calculations more reliable. The main gaps identified include the refinement of models describing the uptake of ions and water by C-S-H, as well as data for ASR products and zeolites.