Here's your strange scientific development of the day: Scientists have invented a kind of "living concrete" that's designed to regrow itself to repair cracks. Sound crazy? Just wait till you hear what it's made of.
But first, why would anyone want to grow concrete? Architects have been using concrete to construct buildings for centuries now, dating back to the Romans and the Pantheon. That means it's used in a LOT of places. After all, it is the world's most common building material.
Over time, all concrete will eventually crack. These cracks can bring down the building by letting concrete's mortal enemy, water, into its structure. Here's how. Most concrete is reinforced with iron or steel rods. When water leaks in through cracks, those rods begin to rust. Rust or corrosion causes the rods to expand, further cracking the concrete allowing in even more water. Without maintenance to seal up the cracks, this cycle continues leading to destruction of the building.
By using a specific type of bacteria, Henk Jonkers of Delft University of Technology, in the Netherlands, has discovered a way to actually grow concrete to automatically fill these cracks, making a building or structure's lifespan much longer.
What Jonkers developed is being called bioconcrete and it uses a bacillus bacteria, referred to as a "healing agent." The bacterial spores are included in the concrete mixing process where they remain inactive. If the concrete cracks and water is introduced, the bacteria germinates and begins to thrive. But the bacteria need food, so this process includes packets of bacterial food, calcium lactate, encased in plastic capsules. When exposed to the same moisture that activates the bacteria, the capsules burst open, feeding the bacteria.
But how does the bacteria repair the concrete? This strain of bacteria produces calcite, also known as limestone, as a byproduct. As the bacteria live and reproduce, calcite is produced and fills in the cracks.
Could this finding be a game changer? Jonkers sure hopes so:
"It is combining nature with construction materials," he says. "Nature is supplying us a lot of functionality for free -- in this case, limestone-producing bacteria. If we can implement it in materials, we can really benefit from it, so I think it's a really nice example of tying nature and the built environments together in one new concept."
Watch the video below from CNN to see it in action. It's just amazing!