Synthesis and Characterization of Composite Eco-Bricks from Waste Plastic, Foundry Sand, and Boiler Ash: A Novel Approach to Sustainable Construction Materials

Abstract

The exponential generation of plastic waste, foundry waste sand (WFS), and coal boiler ash presents a dual challenge of environmental degradation and resource management. This study investigates the feasibility of manufacturing composite eco-bricks by integrating these three industrial waste streams as primary constituents. Bricks were synthesized using a waste material proportion of 46:46:8 (plastic waste: foundry sand: boiler ash) and subjected to comprehensive laboratory characterization including compressive strength testing, water absorption analysis, melting point assessment, and mortar bonding evaluation. Results demonstrated a compressive strength of 8.66 N/mm², representing a 148% improvement over conventional bricks and exceeding the minimum threshold of 3.5 N/mm² specified by Indian Standards (IS 1077:1992). Water absorption was significantly lower than conventional burnt clay bricks, indicating superior durability characteristics. The bricks exhibited successful adhesion with specialized AAC (Autoclaved Aerated Concrete) block bonding agents, confirming structural viability. This research demonstrates that waste-derived composite bricks represent a technically sound and environmentally sustainable alternative to conventional construction materials, simultaneously addressing waste management challenges and reducing landfill burden. The economic and environmental benefits of this approach have substantial implications for circular economy practices in the construction industry.