In the quest to build a more sustainable future, researchers are turning to construction and demolition waste as a valuable resource rather than a disposal problem. A recent study led by Milan Stamenić from the University of Belgrade’s Faculty of Civil Engineering is shedding light on how fine recycled concrete aggregates (FRCA) can be better integrated into new concrete mixes, potentially revolutionizing the construction industry and offering significant benefits to the energy sector.
Stamenić and his team have been exploring the challenges and opportunities presented by FRCA, which is produced from crushed waste concrete. Unlike natural sand, FRCA retains hardened or partially hardened cement paste, making it more porous and angular, with higher water absorption (WA). This characteristic has been a significant barrier to its widespread use in recycled aggregate concrete.
“The high water absorption of FRCA is a double-edged sword,” explains Stamenić. “On one hand, it can lead to issues like reduced workability and compressive strength in concrete. On the other hand, understanding and managing this property can open up new possibilities for sustainable construction.”
The review published in *Građevinski Materijali i Konstrukcije* (which translates to *Construction Materials and Structures*) examines existing methods for determining WA and the mix-design approaches reported in the literature to compensate for FRCA’s high absorption. The study identifies limitations in current WA determination methods, particularly the requirements for the saturated surface condition in the dry state, and suggests potential improvements.
One of the key findings is that combining water compensation with staged mixing offers a practical basis for wider production of FRCA concrete. This method involves adjusting the water content in the mix to account for the absorption by the FRCA and mixing the materials in stages to ensure optimal workability and strength.
“The energy sector stands to gain significantly from these advancements,” says Stamenić. “By reducing the need for raw material extraction and landfill disposal, we can lower the carbon footprint of construction projects. This aligns with the global push towards more sustainable and energy-efficient practices.”
The study also highlights the potential for further research in this area. More precise WA determination is needed to fully unlock the potential of FRCA in concrete production. As the construction industry continues to evolve, the insights from this research could shape future developments, paving the way for more sustainable and efficient building practices.
In an industry where every innovation counts, Stamenić’s work offers a glimpse into a future where construction and demolition waste is not just managed but transformed into a valuable resource. This shift could have profound implications for the energy sector, driving forward the agenda for sustainability and efficiency. As the world grapples with the challenges of climate change and resource depletion, such advancements are not just welcome but essential.