Hydration of Cement Pastes Using the Cement LC³

Abstract

Nowadays, cement is still one of the most consumed products in the world, and has grown more significantly. Thus, the use of supplementary cementitious materials (SCMs) to some extent reduces the carbon dioxide (CO₂) emissions in the environment, contributing to the formation of a sustainable cement. In this context, Limestone Calcined Clay Cement (LC³) has a mechanical performance similar to the ordinary Portland cement (OPC). This work aims to analyze the evolution of the hydration of the LC³ cement in comparison with the reference cement, according to the existing materials in Brazil. For this, the characterization of Portland cement of high initial resistance (CP V-ARI), metakaolin, and limestone filler was carried out. Pastes with a 45% substitution of Portland cement by these SCMs were prepared in a ratio of 2:1, with 30% of the metakaolin and 15% of the limestone filler. Pastes were prepared according to ABNT NBR 16606 [8] in water/binder ratio of 0.40. To follow the hydration, the X-ray diffraction (XRD) assays were performed, at the ages of 1, 3 and 7 days. The results indicated a change in the formation of the hydration products of the LC³ cement compared to the reference paste over the ages.