Simulation of low-heat Portland cement permeability and thermal conductivity using thermodynamics

Based on the CemData18 thermodynamic database, Gem-Selektor v3.3 (Gems) software and Matlab were used to establish a hydration model for low-heat Portland (LHP) cement. Matlab was used to create a simulation program for LHP cement hydration, and for calculating permeability and thermal conductivity based on fractal theory. The research results showed that water/cement (w/c) ratio, curing temperature and hydration time are important factors affecting the hydration of LHP cement. The larger the w/c ratio, the fewer hydration products produced in the cement paste, the looser the skeleton of the cement paste, the higher the porosity and the lower the thermal conductivity. It was also find that the higher the w/c ratio, the higher the permeability of the LHP cement paste, and that the influence of curing temperature on the thermal conductivity of cement paste is mainly reflected in the early stage of hydration.