Avaliação das propriedades físico-químicas, mecânicas e térmicas de argamassas LC³ com baixos teores de cimento Portland

Abstract

Faced with the search for widely available additions capable of replacing considerable levels of Portland cement (CP), LC³ (Limestone Calcined Clay Cement) is a ternary binder formed from a combination of clinker, calcined clay (AC), limestone filler (FC) and gypsum. In LC³, a 50% replacement of CP has been reported as the most promising, however, it is increasingly understood that the ideal replacement content depends on the physical and chemical properties of the clinker and clay used. In this study, LC³ mortars with different Portland cement contents (100%, 55%, 50%, 45% and 40%) and a combination of metakaolin (MC) and FC (0%, 45%, 50%, 55% and 60%), in a 2:1 ratio, were evaluated in the fresh, microscopic, mechanical and thermal state; so that LC³ mortars with Portland cement contents as low as 40% met the regulatory requirements for wall and ceiling cladding. In addition, the incorporation of MC and FC in favor of reducing CP consumption generated mortars with lower densities, resulting in a lighter material with better thermal insulation capacity, with a reduction of up to 4 ºC in the equilibrium plateau temperature for LC³ - 55, LC³ - 50, LC³ - 45 mortars; and 2.5 ºC for mortar with lower CP content (LC³ - 40). This study provides data for a better understanding of the feasibility of using LC³ cement as an alternative binder for coating mortars