Utilization of electronic plastic waste as fine aggregate with and without silica fume in concrete: experimentation...

The depletion of natural resources has created an urgent need to identify alternative, sustainable materials for construction. Simultaneously, the rapid global accumulation and improper disposal of electronic waste (E-waste), particularly in developing countries, have raised significant environmental and public health concerns. This study investigates the use of electronic plastic waste (E-PW) as a partial replacement for fine aggregate in concrete, with replacement levels of 5%, 10%, 15%, and 20% evaluated at different curing ages. While the inclusion of E-PW led to reductions in mechanical and durability performance compared to conventional concrete, these effects were mitigated by replacing 10% of the cement with silica fume (SF). The enhancement provided by SF demonstrated improved strength and performance in the E-PW concrete mixtures. According to SEM results, SF highlights the interfacial transition zone (ITZ) associated with E-PW in the OPC matrix. The best performing mix for blends containing E-PW and SF were M7 (5% E-PW + 10% SF), achieved a compressive strength of 37.69 MPa, a flexural strength of 5.36 MPa, and a splitting tensile strength of 3.91 MPa at 56 days, surpassing those of the reference concrete. An environmental perspective, life cycle assessment demonstrated that a 20% replacement of fine aggregates with E-PW reduced the overall environmental burden by 5.3% and lowered the global warming potential by 1.43%, equivalent to saving approximately 4-5 kg CO₂-eq per cubic meter of concrete. Hence, the findings support the potential for producing eco-efficient concrete by partially replacing natural sand with E-waste, contributing to resource conservation and environmental sustainability.