“Optimization of non-standard concrete by replacing the fine aggregate with copper slag and adding of copper fiber

Resumen

Abstract– This research aimed to optimize the mechanical behavior of concrete made with non-standardized aggregates by partially replacing the fine aggregate with copper slag in proportions of 0.5%, 1%, and 1.5%, and to evaluate the combined effect of this substitution with the addition of 40 g of copper fiber. The study was experimental, with a quantitative approach and a quasi-experimental design. A total of 63 cylindrical specimens measuring 4” × 8” were prepared and tested after 7, 14, and 28 days of curing, according to Peruvian standards NTP 339.033 and NTP 339.034. The results showed that the incorporation of copper slag positively influences the compressive strength of the concrete, especially at low proportions. At 28 days, the control sample reached an average compressive strength of 286.20 kg/cm2, while the mixture with 0.5% copper slag achieved 280.91 kg/cm2 and the mixture with 1.5% slag reached 290.43 kg/cm2. Furthermore, the combination of 0.5% copper slag with 40 g of copper fiber exhibited the best overall performance, achieving an average compressive strength of 293.68 kg/cm2 at 28 days, surpassing the control concrete and easily meeting the minimum strength required by Peruvian Technical Standard E.060 (f’c = 210 kg/cm2). In conclusion, the partial substitution of fine aggregate with copper slag, especially in low proportions and in combination with copper fiber, improves the compressive strength of concrete made with non-standardized aggregates. Furthermore, this alternative contributes to the utilization of industrial waste, reducing environmental impact and production costs, making it a technical, economic and sustainable solution for the construction industry.