Durability Analysis of Concrete with the Substitution of Natural Aggregates by Copper and Pig Iron Waste

Background: The global scenario demands immediate actions to mitigate the environmental imbalances threatening the planet, reflected in natural disasters such as storms, floods, and severe droughts. This study evaluates the durability of concrete in the face of these challenges through carbonation, chloride penetration, and alkali-aggregate reaction tests, exploring the feasibility of producing sustainable concretes using copper ore waste and pig iron slag, available in the southern and southeastern regions of Pará due to the local mining activity. Materials and Methods: The methodology of the study involved the collection of copper waste and blast furnace slag, which were characterized through granulometric analysis, X-ray Diffraction (XRD), and X-ray Fluorescence (XRF). These materials were used as partial substitutes for fine and coarse aggregates in the production of concretes with different dosages. Durability tests were conducted, including accelerated carbonation, chloride penetration, and alkali-aggregate reaction. The analysis of the results aimed to assess the feasibility of these wastes as sustainable alternatives for civil construction. Results: The statistical results showed significance in the substitution of waste materials, highlighting copper waste and blast furnace slag as promising alternatives. The accelerated carbonation tests revealed that concretes with 75% and 100% waste exhibited lower susceptibility to CO₂ due to reduced porosity. In the chloride penetration test, concretes with 25% and 75% waste demonstrated lower NaCl penetration, indicating superior resistance. Furthermore, in the alkali-aggregate reaction test, the waste samples showed no reactive potential, as per NBR 15577-4, confirming their suitability for concrete production. Conclusion: A comparative analysis of the properties of these concretes in relation to conventional concrete revealed significant potential for replacing natural aggregates with waste materials that would otherwise be discarded, contributing to the reduction of environmental impact.