Analysis of the physical-mechanical performance of the concrete partially substituting the cement by nanosilica and the coarse aggregate by rock wool

Bravo A.N.; Gallardo W.J.; Muñoz S.P.; Rodriguez E.D.; Fernández J.P. · Ingeniare (2024) · DOI: 10.4067/s0718-33052024000100218

Resumen

The excessive production of concrete has led to the overexploitation of natural resources, prompting the exploration of high-strength alternative materials like nanosilica (NS) as a superplasticizer substituting cement and rock wool (LR) used in bulk as a partial substitute for coarse aggregate. In this experimental study, both materials are proposed to be incorporated into concrete production with varying percentages: 0.6%, 0.8%, 1.0%, and 1.4% of NS by weight, and 2%, 4%, 6%, and 8% of LR by volume. The objective is to evaluate their physical and mechanical performance, including settlement properties, air content, and mechanical strength. The results indicated a significant increase in settlement with NS, reaching up to 8”. Air content decreased to 0.7% with 0.8NS but increased with LR. Additionally, at 28 days, compression resistance increased by 37.19% and 30.53% for C-1 and C-2, respectively, with 1.4%NS compared to the control model. Furthermore, with 1.4%NS+6%LR, it increased by 21.85%. In traction, samples with 1.4%NS increased by 24.10%, and those with more than 6%LR increased by 16.57%. Furthermore, flexion increased by 18.84% for 1.4%NS and 26.68% for 1.4NS+8LR. The study concludes that the optimal addition is 1.4% NS and 6% LR, significantly enhancing the mechanical resistance of concrete compared to control designs.

Instituciones: Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas; Universidad Señor de Sipán