Estudo da incorporação de lodo de esgoto calcinado em argamassas como substituto parcial do cimento Portland

A major challenge for civil construction is the ingress of innovative techniques that do not only reduce the cost of construction, but at the same time also reduce the environmental impacts. In this research, we evaluated the performance and durability of coating mortars produced in different proportions incorporating calcined sewage sludge in distinct percentages partially replacing the Portland cement. For this purpose, sewage sludge was calcined at temperatures 600oC, 700oC, 800oC and 900oC and characterized by physical, chemical, mechanical, environmental and morphological assays. After a study of the characterizations, we opted to use the calcined sludge at 800oC to produce the mortars for having presented pozzolanic reactivity. The mortars were produced in proportions 1:3, 1:4.5 and 1:6 and characterized in the fresh state through the index of consistency, density, incorporated air content and water retention. In the hardened state they were characterized by tensile strength in flexion, compressive strength and mass density. Aiming to evaluate the durability of the mortar produced, water absorption assays were carried out by capillarity, capillary coefficient, tensile adhesion resistance, accelerated aging by wetness cycles and drying and analysis of carbonation resistance. Thermogravimetric analysis was performed, as well as the final microstructural of mortars. Reference mortars were produced allowing the comparison of the results. In line with the studies already conducted worldwide on the incorporation of calcined sewage sludge as cementitious material and by comparing the results obtained with the reference mortars, it was concluded that the incorporation of sewage sludge Calcined at 800oC did not impair the performance or durability of the studied mortars, being 10% and 20% the most viable incorporation percentages technically produced in proportions 1:3 and 1:4.5.