Caracterização de propriedades no estado endurecido de argamassa LC³ para 3DCP

Abstract

In view of the stagnation of innovation in the construction sector compared to other industries, measures need to be taken to fill the gaps of digitalization in the construction industry. This has led to the development of 3D printed concrete (3DCP), which uses a mixture with a high cement content. The need then arose to reduce the amount of clinker in the cement composition by adding supplementary cementitious materials, in this case: metakaolin and limestone filler, forming the LC³ ternary mix. In this study, the clinker was reduced by 45%, replacing it with 30% metakaolin and 15% limestone filler by mass, forming a finer material with different properties. This work therefore aims to characterize its properties, which are important for 3DCP in the hardened state. The use of these supplementary materials did not lead to high variations in compressive strength and tensile strength, both of which were compatible with what is required for the printing system, as well as absorption and void ratio. With regard to the microstructure, a finer grain size was observed, as well as changes in the products formed by the pozzolanic reactions, where portlandite was consumed in the LC³ mixture.