Effect of Polypropylene Fibres and Silica Fume on the Compressive Strength of Concrete Incorporating Recycled Aggregate

Jesús Manuel Huayta Poma J.; Challco Mamani G.; Paul Linaja Ayala J. · Proceedings of the LACCEI international Multi-conference for Engineering, Education and Technology (2026) · DOI: 10.18687/laccei2026.1.1.1086

Resumen

This article evaluates the influence of Polypropylene Fibers (FPP) and Silica Fume (HS) on the mechanical properties of a concrete with design compressive strength f'c = 210 kg/cm2 incorporating Recycled Coarse Aggregate (AGR), as a sustainable alternative that reuses construction and demolition waste. The aggregates were characterized in accordance with ASTM standards, and the mix was designed using the ACI 211.1 method. Nine mixtures were produced in a Taguchi L9 orthogonal array, combining three levels of AGR (20, 50, and 100%), FPP (0.3, 0.5, and 0.7%), and HS (5, 7, and 9%). The slump of the nine mixtures and the 28-day compressive strength of 36 cylindrical specimens were measured. The results show that slump values ranged from 3.1 to 3.8 in, slightly lower than the theoretical slump of 4 in. Likewise, all mixtures exceeded the design strength, with values between 225.95 and 295.08 kg/cm2 representing increases from 7.6% up to 40.5% with respect to 210 kg/cm2. Furthermore, the optimal mix corresponded to 50% AGR, 0.7% FPP, and 9% HS. In conclusion, the combined incorporation of AGR, FPP, and HS makes it possible to produce concrete with f'c = 210 kg/cm2 that exhibits controlled workability and mechanical performance superior to conventional concrete.

Instituciones: Universidad Tecnológica del Perú