Caracterização de argamassa LC³ no estado fresco para 3DCP

Abstract

Amid the enormous scientific and technological advances in the field of civil construction, the search for new technologies and construction techniques is inevitable, especially due to the growing concern about the climatic and environmental impacts caused by polluting materials. In this context, calcined clay mortar (LC³) emerges as a material with a lower concentration of clinker. This study aimed to explore the potential of this mortar in the 3D printing process. For this purpose, comparisons were made between two samples: an LC³ sample, composed of 55% Portland cement, 30% metakaolin, and 15% limestone filler, and a conventional cement sample composed of 100% Portland cement. Both were evaluated in their fresh state through slump and spread tests, mass density, and squeeze-flow. Following this, the 3D printing process (3DCP) of the two mixes was carried out. The incorporation of metakaolin and limestone filler in the LC³ sample resulted in slight changes in the mass density of the final material, due to the slightly different densities of these materials compared to conventional cement. The yield stress of the LC³ mix showed lower values at 15 and 30 minutes compared to the 100% Portland cement mix, indicating easier flow during the printing process. Additionally, it was possible to conclude that the inclusion of supplementary cementitious materials led to a decrease in slump and spread values, but still allowed the mortar to be adequately printed.