Argamassas Sustentáveis com LC³: avaliação de propriedades mecânicas e microestruturais em idades avançadas

Abstract

The construction industry is essential for urban, economic, and social development; however, the production of clinker, a key raw material in this sector, is responsible for significant carbon dioxide (CO₂) emissions into the atmosphere. In search of more sustainable alternatives, this study aimed to evaluate the impact of partially replacing Portland cement (PC) with high clinker content by a combination of metakaolin (MK) and limestone filler (LF) in rendering mortars. The proportions of PC used ranged from 40% to 55%, while MK and LF (in a 2:1 ratio) ranged from 45% to 60%. Physical, microstructural, and mechanical properties were investigated at 56 and 200 days. The results showed an increase in strength from 56 to 200 days in all mixtures, with LC³-55 achieving values close to the reference (REF) in both periods. The presence of C-A-S-H was also observed in the ternary mixtures. Regarding workability, a decrease in the setting time (both initial and final) was noted in the ternary mortars. Additionally, it was found that the samples produced with the ternary formulation are more permeable to water by capillarity than traditional cement.