The invention of 'self-healing' concrete.

Self-healing concrete, which repairs itself using light and microorganisms, is considered a revolutionary breakthrough that could drastically reduce construction repair costs and extend the lifespan of infrastructure for centuries.

If widely adopted, self-healing concrete could significantly reduce building maintenance costs - Photo: Quantum News

According to The Brighter Side of News , the self-healing concrete invention belongs to a research team at the University of Nebraska-Lincoln (USA) and is being highly praised for its practical applications, not only in the construction industry.

Why are concrete cracks a serious problem?

Concrete is the most widely used building material in the world . However, it is prone to developing small cracks due to the effects of heat, shrinkage, or heavy loads.

These cracks can allow water, air, and chemicals to penetrate, causing corrosion of the reinforcing steel and weakening the structure, potentially leading to collapse if not detected and treated promptly.

In the United States, detecting and repairing concrete cracks costs tens of billions of dollars annually. This is a difficult process, requiring precise location of the damage and the implementation of costly repair measures.

Under the leadership of Dr. Congrui Grace Jin, the research team drew inspiration from lichens, a symbiotic organism between fungi and algae/cyanobacteria capable of surviving in harsh environments.

They recreated this symbiotic model in the laboratory by combining filamentous fungi (Trichoderma reesei) and cyanobacteria (Anabaena inaequalis or Nostoc punctiforme) to create a microbial system that can survive on air, water, and light alone.

The unique feature of this system is its ability to automatically produce calcium carbonate, a mineral that seals cracks in concrete without the need for external nutrient supplementation, unlike previous methods.

In this microbial ecosystem, cyanobacteria use light for photosynthesis, absorbing carbon dioxide and nitrogen from the air to produce nutrients. Filamentous fungi use these nutrients to grow and produce calcium carbonate crystals that fill cracks.

Experiments have shown that this symbiotic microbial system thrives in nutrient-poor, low-humidity, and high-pH environments like concrete, something many other bacteria cannot do. Tests also confirmed a crack healing rate up to 80% faster than with conventional bacterial methods.

In particular, this method is also environmentally safe because it does not produce toxic gases like some techniques that use urea.

Practical applications and future prospects

If widely adopted, self-healing concrete could significantly reduce maintenance costs, extend the lifespan of bridges, roads, buildings, and even space structures on the Moon or Mars, where repairs are nearly impossible.

The research team is also currently collaborating with sociologists to understand public perception of living in homes with microorganisms "hiding" in the walls. Legal and ethical factors are also being considered to ensure safety and social acceptance.

Not stopping at theoretical models, the team of scientists created concrete samples containing microorganisms, cultivating them under conditions simulating real-world conditions such as warm temperatures, average humidity, and light cycles as on a construction site. The results showed that this microbial system could grow and function effectively without gene editing, relying only on air and light.

If commercialized, this technology could revolutionize the global construction industry, making cities more sustainable, with lower emissions, and safer for everyone.

MINH HAI

Source: https://tuoitre.vn/phat-minh-loai-be-tong-tu-va-20250623113630787.htm