In the heart of Nepal, researchers are pioneering a sustainable solution to a global problem, one that could reshape the construction industry and offer significant benefits to the energy sector. Kameshwar Sahani, a civil engineering professor at Kathmandu University, is leading the charge in exploring the potential of recycled aggregate concrete (RAC), derived from construction and demolition waste (CDW). His work, recently published in *Engineering Reports* (translated to English as *Engineering Reports*), is a beacon of hope for a more sustainable future.
The global demand for concrete is insatiable, driven by rapid urbanization and industrialization. However, the extraction and processing of natural aggregates, which make up 70-80% of concrete, come at a significant environmental cost. “We’re depleting our natural resources at an alarming rate,” Sahani explains, “and the environmental impact is substantial.”
Enter RAC, a sustainable alternative that transforms CDW into a valuable resource. “We’re not just reducing waste,” Sahani says, “we’re creating a circular economy where old infrastructure fuels new construction.”
But the journey isn’t without challenges. RAC is often plagued by high porosity, elevated water absorption, and reduced mechanical and durability performance. To overcome these hurdles, Sahani and his team are exploring innovative strategies, such as incorporating supplementary cementitious materials like fly ash and silica fume, advanced mixing techniques like the Two-Stage Mixing Approach (TSMA), and fiber reinforcement.
The implications for the energy sector are substantial. Buildings constructed with RAC could significantly reduce their carbon footprint, a critical factor in a world increasingly focused on sustainability. Moreover, the use of RAC could lead to cost savings, as the material is often cheaper than natural aggregates.
Sahani’s research also delves into the role of numerical models and machine learning in optimizing RAC mix designs and predicting its behavior. This could revolutionize the way we approach construction, making it more efficient and sustainable.
Life Cycle Assessment (LCA) is another crucial aspect of Sahani’s work. By quantifying the environmental benefits of RAC, he’s providing valuable insights into its long-term viability. “We’re not just looking at the here and now,” Sahani explains, “we’re considering the bigger picture.”
The research also highlights the need for standardized RCA processing methods and long-term field validations. This could pave the way for widespread adoption of RAC, shaping the future of construction and offering significant benefits to the energy sector.
As we stand on the brink of a sustainable revolution, Sahani’s work serves as a reminder that the solutions to our most pressing challenges often lie in innovative thinking and a commitment to sustainability. His research, published in *Engineering Reports*, is a testament to the power of human ingenuity and a beacon of hope for a greener future.