In the quest for sustainable and affordable housing solutions, a team of researchers led by Muhammad Irfan-ul-Hassan from the University of Engineering and Technology in Lahore, Pakistan, has made significant strides. Their work, recently published in *Next Sustainability* (which translates to *Next Sustainability* in English), explores the potential of supplementary cementitious materials (SCMs) in creating eco-friendly and cost-effective building materials. The findings could reshape the construction industry’s approach to low-cost housing and sustainable development.
The research focuses on partially replacing Ordinary Portland Cement (OPC) with SCMs such as fly ash, bagasse ash, and calcined red mud (Calcined Clay Cement C3) in various building materials like mortar, concrete, bricks, blocks, and pavers. The team employed three techniques—vibration, energy-intensive, and vibro-compaction—to optimize the production process.
One of the standout findings is the 20% replacement of fly ash in concrete, which achieved a 90-day compressive strength of 37 MPa. This not only reduced CO₂ emissions by 61 kg per cubic meter but also lowered the cost from PKR 420 to PKR 374 per cubic meter. “The reduction in both emissions and cost makes this a viable option for large-scale applications,” said Irfan-ul-Hassan, highlighting the dual benefits of sustainability and affordability.
Similarly, the 20% calcined red mud mix reached 38 MPa at 90 days, demonstrating the potential of alternative materials in achieving high strength. For mortar, the F20M mix achieved 27.3 MPa at 90 days, reducing CO₂ emissions by 84.5 kg per unit and lowering the cost index from 0.97 to 0.88. The OB-4 brick mix, composed of 5% OPC, 20% fly ash, 25% bagasse ash, 30% fines, and 20% coarse aggregates, achieved a 56-day compressive strength of 12.1 MPa. This mix reduced CO₂ emissions from 585 kg to 202.5 kg per 1000 units and lowered the cost index from 1.75 to 1.46.
The optimized paver mix, F20P-E2, reached 29.5 MPa at 56 days, reducing CO₂ emissions by 116 kg per unit. These findings underscore the potential of SCMs in creating sustainable and cost-effective building materials.
The research also revealed that vibration techniques were more effective for coarse aggregate-rich units, while energy-intensive techniques performed better for finer aggregates. This insight could guide future production processes, optimizing both cost and efficiency.
The incorporation of SCMs led to a significant reduction in CO₂ emissions and overall material costs, aligning with the Sustainable Development Goals (SDGs) 11, 12, and 13. “This study supports the development of sustainable, eco-friendly construction materials that align with cost reduction goals and carbon footprint minimization,” Irfan-ul-Hassan emphasized.
The commercial implications for the energy sector are substantial. As the demand for sustainable construction materials grows, the adoption of SCMs could reduce the industry’s reliance on energy-intensive cement production. This shift could lower operational costs and contribute to a greener future.
The research published in *Next Sustainability* offers a promising path forward for the construction industry. By leveraging SCMs, developers can create affordable and sustainable housing solutions, reducing both environmental impact and financial burden. As the world grapples with climate change and urbanization, this research provides a beacon of hope and innovation.