Hydrated Products Influencing the Thermal Conductivity of Cement-Based Foam with Pozzolan

This experimental study reports the weighted fraction of hydrated products of cement-based foam and examines their influence on pozzolans and thermal conductivity. These hydrated products were formed as the result of hydration in the cement-based foam mixtures prepared by substituting cement with fly ash, silica fume, and metakaolin, up to 20% by weight in the binder. To monitor the maturity of the hydration products, three different hydration periods, namely 60th, 120th, and 210th day, were selected. X-ray diffraction technique was used here for the identification of phase spectrums while the Rietveld quantitative X-ray diffraction method was employed for the quantification of the weighted fraction of hydrated products. The weighted fraction results showed that the consumption of portlandite (CH) increases with the inclusion of pozzolan and the higher substitution ratio further increases this consumption. In addition, the results reveal that the portlandite (CH) and calcium silicate hydrate (CSH) govern the thermal conductivity of cement-based foam mixture including those blended with pozzolan.