Efeito da substituição parcial do agregado graúdo por escória de alto-forno nas propriedades mecânicas de concretos

Abstract

The blast furnace slag charcoal is waste generated from the production of pig iron in blast furnaces. In the steel mills operating in blast furnace waste generation is approximately 250 kg per ton of pig iron produced. In this sense, the state of Pará figure as the second largest domestic producer of pig iron, reinforcing the importance of having a more detailed scientific research in order to minimize the environmental impact caused by the accumulation of this waste through the development of appropriate applications. In this context the present research aims to determine the mechanical properties of concrete produced with the partial replacement of natural coarse aggregate (AGN) for blast furnace slag (EAF). For this we performed a beneficiation process of the EAF by crushing in a jaw crusher and screening, then it performed a dose of study concrete with 100% AGN was performed immediately replacing (by mass) of natural aggregate by aggregate of blast furnace slag (0% - reference, 20%, 30% and 40%). tests were carried out in the fresh state (consistency) and in the hardened state (compressive strength, tensile strength and modulus of elasticity) of concrete produced with partial replacement of AGN by EAF at the ages of 28 and 63 days as well as scanning electron microstructure (SEM) of concrete. The results showed that the incorporation of the EAF in the mixture caused a gradual decrease in concrete workability. As well as the mechanical performance increased significantly compared to conventional concrete from the incorporation of 30% of EAF. Thus, incorporation of this waste in special concrete production improvements induced responses in all the analyzed mechanical properties when compared to conventional concrete.