Estudo de argamassa estrutural com adição de resíduo da mineração de ferro depositado em barragem de lama no estado de Minas Gerais - Brasil

Abstract

There are many studies initiatives in the attempt to apply iron ore tailing to civil construction materials, such as concrete making, building blocks, paving and mortar. However, in most cases, it is necessary to deepen not only the technical studies, but also the dosages and applicability. The mining companies themselves have shown interest in these studies, since the correct allocation of the tailing of iron ore (IOT) and great environmental inspection corroborate for very onerous actions. The objective of this work is to discuss and to analyze an alternative of reutilization of tailing obtained by the processing of iron ore and deposited in mud dam, in the construction of structural mortars, in the form of addition. It was verified the chemical presence of Quartz-SiO₂, Hematite-Fe₂O₃, Goethite-FeO (OH) and Gibbsite-Al (OH) ₃. No chemical or mineralogical components were found that could compromise the quality of the composites cations with possible deleterious reactions, having a specific mass of 4,04 g / cm³. By evaluating the performance properties of the structural mortar both in the fresh and hardened state, it was observed that the final product did not require more kneading water due to the reduced pore content, proving to be a material with great potential to act as a filer. In the study of the experimental dosage and the identification of the optimum utilization level of the IOT, they were characterized by the molding of structural mortar with proportions of 10%, 20%, 30% and 40% of the addition of the IOT and later submitted to tests. Mortars with addition of RMF showed small increase in material density, reduction in void indices, decrease in water absorption in hardened state and better mechanical properties when compared with reference traces. The results indicate that additions of even higher contents maintain the mechanical properties and improve the pore closure caused by the filer effect of the product, providing indications of good durability of the material, evidencing evidence of the technical feasibility of the material being studied.