Análisis del efecto de la adición de fibras de cabuya en la resistencia a compresión del hormigón f´c= 210 kg/cm2

Abstract

This experimental research evaluates the mechanical feasibility of incorporating raw cabuya fibers into a structural concrete matrix with a specified compressive strength of f'c = 210 kg/cm², conducted at the laboratories of the Universidad Técnica de Ambato. The methodology comprised two phases. In the first, aggregates from Mina Cristóbal were physically and mechanically characterized per NTE INEN standards 696, 856, 857, 858, and 860, yielding a fineness modulus of 3.00, nominal maximum size of ½", and abrasion loss of 21.32%. Type IP cement specific gravity was determined at 2.991 g/cm³ (NTE INEN 156). The control mix was proportioned using the ACI 211.1 method, establishing a water-to-cement ratio of 0.56. In the second phase, cylindrical specimens were cast with fiber mass additions of 0%, 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%, tested under uniaxial compression at 7, 14, 21, and 28 days per NTE INEN 1578. The control concrete achieved 250.17 kg/cm² at 28 days, exceeding the theoretical requirement by 19.1%. Fiber incorporation induced progressive strength reductions: 122.70 kg/cm² at 0.5% and 14.24 kg/cm² at 2.5%, representing decreases of 50.9% and 94.3% respectively. No modified specimen reached the required structural threshold. It is concluded that untreated cabuya fiber severely compromises concrete mechanical performance, precluding its direct structural application. Alkaline surface treatments and dosages below 0.5% are recommended for future research.