Strength and environmental evaluation of building bricks using industrial waste for liveable environments

Abstract

Researchers around the world have been enthusiastically using industrial waste to develop eco-friendly building materials. The main objective of this study was to explore the potential of using local industrial waste, such as Solid Waste Fly Ash (SWFA) and Paint Sludge (PS), as alternative to non-renewable laterite soil. During the preliminary stage, compacted cylinders of two systems were investigated: Laterite Soil (LS) and SWFA at 50:50 ratio, and a combination of LS, SWFA and PS (LSP) at 50:25:25 ratio. Traditional stabilisers Hydrated Lime (HL) and Ordinary Portland Cement (OPC), as well as Ground Granulated Blastfurnace Slag (GGBS), were used at different ratios (10%, 20%, 30% and 40%) for these cylinders. The cylinders were cured for 7, 28 and 60 days prior to strength and water absorption test. The results showed that 30% stabiliser dosage provided the best strength and economic benefits. Based on these findings, pilot industrial and commercial trials were conducted using full-sized unfired bricks. The LSP brick system with the blended stabiliser HL-GGBS performed exceptionally well in terms of engineering properties. The investigation suggests that SWFA and Paint Sludge can be promising substitutes for clay in unfired bricks production, promoting waste recycling and reducing the impact of landfills. Using local available waste materials to manufacture unfired bricks present a viable alternative to fired bricks, especially in low-load bearing situations. This research contributes to innovation, enhanced waste management, and the concept of green building. Moreover, it minimizes energy usage and hazardous emissions associated with brick firing, aligning with the Sustainable Development Goals (SDGs).