Influência da substituição parcial do cimento por sílica ativa nas propriedades de argamassas com agregado reciclado de concreto.

Abstract

The main objective of this dissertation is to evaluate the effect of partial replacement of cement by silica fume on the physical-mechanical behavior of coating mortars with recycled concrete aggregate (RCC) and to analyze its environmental impacts, considering CO2 emissions and energy consumption. generated in the production of mortar raw materials. We tried to evaluate the influence of recycled aggregates in proportions of 1:3 and 1:4 (in mass) by partially replacing the natural aggregate with 0%, 30% and 50% RCC, and each of these groups was subdivided with substitutions partial cement by silica fume in the contents of 0%, 5%, 10% and 15%. The results allow concluding that the increase in the recycled aggregate content in the mortars impacts on its rheology and reduces its mechanical properties compared to the reference one, being softened with the incorporation of silica fume. Regarding environmental impacts, cement was the main cause of impacts. Samples R0S15 present the highest cement consumption in both the 1:3 and 1:4 mixes and, therefore, generate greater impacts. However, the impacts generated per unit of resistance show an inverse situation. Therefore, despite generating higher CO2 emissions and energy consumption, their contribution to resistance reflects greater sustainability.