In the heart of China’s Heilongjiang Province, researchers are tackling a global challenge: how to make construction more sustainable. Jinglei Liu, a professor at Qiqihar University’s College of Architecture and Civil Engineering, is leading a team that’s exploring innovative ways to enhance recycled aggregate concrete (RAC), a material that’s gaining traction in the construction industry. Their findings, published in the journal Buildings (translated as “建筑” in Chinese), could have significant implications for the energy sector and beyond.
The team’s research focuses on improving the mechanical properties of RAC by incorporating industrial byproducts like copper slag (CS), ground granulated blast furnace slag (GGBS), and basalt fiber (BF). “We’re facing sand and gravel shortages, construction waste accumulation, and ambitious ‘double carbon’ goals,” Liu explains. “Our work is about turning these challenges into opportunities for green, low-carbon building materials.”
The results are promising. By adding 20% GGBS to RAC, the team observed a 21.3% increase in compressive strength after 28 days. But the real game-changer was the combination of 10% CS and 10% GGBS, which boosted compressive strength by 25.6%, split tensile strength by 29.7%, and flexural strength by 16.6%. Adding 0.2% BF to this mix further enhanced these properties, with compressive strength increasing by 31.3%.
These improvements could have significant commercial impacts. “The energy sector, in particular, stands to benefit from these advancements,” says Liu. “More durable, sustainable construction materials can lead to longer-lasting, lower-maintenance infrastructure, reducing the sector’s carbon footprint and energy consumption.”
The team’s research also sheds light on the underlying mechanisms driving these improvements. Using techniques like X-ray fluorescence (XRF), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), they’ve gained insights into how these additives interact at the microscale.
So, what does this mean for the future of construction? Liu believes these findings could pave the way for wider adoption of RAC in civil engineering projects. “We’ve provided a solid theoretical foundation and a viable technical pathway,” he says. “Now, it’s about scaling up these innovations and integrating them into mainstream construction practices.”
As the world grapples with climate change and resource depletion, research like Liu’s offers a beacon of hope. By turning industrial waste into valuable construction materials, we can reduce waste, conserve resources, and build a more sustainable future. The journey is just beginning, but the potential is immense.