Instead of costly humans having to maintain and repair the concrete, it would be ideal if the concrete would be able to heal itself. This is now possible with help of special bacteria. These bacteria are called extremophiles, because they love to live in extreme conditions. In dry concrete for example they will not only live, but they will actively produce copious amounts of limestone. With this calcium carbonate-based material the little construction workers can actively repair occurring cracks in a concrete structure.

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