Concrete is the most widely used structural material on the planet, but it has a niggling habit of breaking down over time, giving rise to cracks, pits and holes that require expensive repairs or replacement. But what if concrete could mend itself? It turns out such a material already exists - and it could be used in a building near you in as little as 2-3 years.
The material in question is called "bio-concrete." Born out of a collaboration between microbiologist Henk Jonkers and concrete technologist Eric Schlangen, the cost-saving, self-healing material is a living mixture of concrete, bacterial spores, and microbe-sustaining nourishment in the form of calcium lactate. When the biomaterial is exposed to water (one of the many things known to contribute to the degradation of concrete), the bacteria set to work converting calcium lactate into calcite, which fills in surrounding cracks.
According to the BBC, Jonkers and Schlangen have demonstrated the bacteria's ability to repair cracks up to half a millimeter wide (see the video below for a side-by-side comparison of cracks and holes before and after healing). Now, the researchers are bringing their concrete out of the lab for some practical, real-world testing.
Jonkers says the system could be ready for commercialization in 2-3 years. Assuming all goes well, he says the biggest hurdles will be in upscaling - producing the bacteria in large quantities, and ensuring that they can survive the mixing process.