DELFT UNIVERSITY OF TECHNOLOGY, DELFT, NETHERLANDS. Bioconcrete is a newly developed type of concrete that can heal itself with the use of bacteria. This innovative invention provides long-term durability as this bioconcrete is impervious to the cracking that results from wear and tear.
Professor Henk Jonkers, a microbiologist at Delft University of Technology, developed the bioconcrete when a concrete technologist asked him if it would be possible to utilize bacteria in a way that could allow the concrete to self-repair or heal itself.
It took 3 years of intensive research for Professor Jonkers to answer this question. Concrete with cracks are plagued with leakage that eventually leads to its collapse. He needed bacteria that could survive in the extreme environment of concrete – very dry and stone- like material. Also, concrete is highly alkaline so the healing bacteria must be dormant for years before it gets activated by water.
Professor Jonkers utilized Bacillus bacteria which is a genus of bacteria that can thrive in alkaline conditions. In addition to that, Bacillus can produce spores that are able to survive for decades without oxygen or food. The second challenge that he had was to make the bacteria produce a material that can repair concrete which is a limestone. The bacilli need a food source to produce limestone. Sugar was immediately eliminated since it would create a weak concrete. He utilized calcium lactate. The bacteria and calcium lactate were placed into capsules that were made from biodegradable plastic. These capsules were added to the wet concrete mix.
When cracks develop in the concrete, water enters and opens the capsules. The bacteria germinate, feed on the lactate and multiply. Then they combine the carbonate ions with the calcium to form limestone or calcite that close the cracks in the concrete.
The development of bioconcrete can pave the way for the start of biological buildings. It is a perfect example of combining construction materials with nature. Limestone-producing bacteria can absolutely provide benefits to construction and building materials. It is about time that we take advantage of nature and its abundant supply of functionalities that are absolutely free.
| Invention | Self-Healing Concrete |
|---|---|
| Organization | Delft University of Technology |
| Researcher | Professor Henk Jonkers & Team |
| Field(s) | Construction, Building Materials, Concrete Technology, Microbiology, Construction Materials |
| Further Information | http://edition.cnn.com/2015/05/14/tech/bioconcrete-delft-jonkers/ |
image courtesy of pixabay.com
