Recycled aluminum can fibers for concrete reinforcement: Standardized testing of compressive strength and static elastic modulus

Abstract

This study examines the feasibility of repurposing post-consumer aluminum beverage-can scrap into macro-fibers for concrete reinforcement as a pathway toward more sustainable construction materials. Although aluminum offers low density, inherent corrosion resistance in many environments, and abundant waste streams, data on concrete reinforced with fibers cut from recycled cans remain limited. Cleaned cans were slit into strips of 100 × 10 × 1 mm and added at a 2% fiber volume fraction to a B15 concrete. Cube compressive strength was determined on 150 mm cubes in accordance with TCVN 3118:2022, and the static modulus of elasticity was measured on 150 × 300 mm cylinders following TCVN 5726:2022. Measured moduli were also compared with code-based predictions from ACI 318-19, AS 3600:2018, BS 8110-2:1985, and Eurocode 2 (EN 1992-1-1). Relative to the plain control, the aluminum fiber–reinforced concrete exhibited ~22% lower cube strength (20.6 → 16.1 MPa) and ~11% lower modulus (23.99 → 21.31 GPa). The absolute differences between measured and code-predicted moduli were 5.8% (ACI), 11.3% (AS), 12.6% (BS), and 27.1% (EC2), indicating that current equations are not calibrated for concrete reinforced with recycled aluminum-can fibers. Compared with steel-fiber concrete, aluminum fibers did not enhance compressive strength but may offer benefits in post-cracking toughness, corrosion performance, and circularity. Recycled aluminum-can fibers appear feasible for non-structural or weight-sensitive concrete applications. Future work should optimize fiber geometry and dosage, improve dispersion and constructability, and include standardized flexural tests (ASTM C1609, EN 14651) to quantify post-cracking behavior.