Recycling electronic waste as fiber reinforcement in high-strength concrete: A sustainable approach

The electronic industry's waste products, known as electrical waste fibers (EWF), present an opportunity for sustainable concrete reinforcement. This study investigates the use of EWF, primarily composed of brass fibers, as a natural material for enhancing the properties of high-strength concrete (HSC), addressing its inherent brittleness that often leads to sudden failure at ultimate load capacity. The effectiveness of EWF was evaluated under two scenarios: (1) HSC mixtures containing varying EWF ratios (0 %, 0.5 %, 1.0 %, 1.5 %, 2.0 %, and 3.0 % by volume), and (2) mixtures where steel fibers (SF) replaced EWF. A series of fresh, hardened, and morphological property tests were performed. The highest compressive strength of 54.77 MPa was achieved at 1.5 % SF, while the maximum tensile strength using EWF was observed at 3.0 % content, though with a reduced compressive strength of 40.74 MPa. Flexural strength reached 6.98 MPa at 1.5 % SF and decreased with higher dosages. Splitting tensile strength improved significantly in SF mixes, with up to a 20.92 % increase at 1.5 % SF content, whereas EWF mixes showed moderate gains. The modulus of elasticity improved by 14.72 % at 1.5 % SF and 12.25 % at 1.0 % EWF compared to the control mix. Optimal performance was achieved at 1.0 % EWF and 1.5 % SF, beyond which mechanical properties declined due to increased porosity and reduced structural continuity. These findings demonstrate the potential of EWF as a sustainable reinforcement material for HSC, contributing to enhanced durability and resource conservation.