If you’ve ever had to seal a crack in concrete, you know what a pain it can be and how quickly cracked concrete can begin to disintegrate. That’s why we’re so excited about a new technology that would allow concrete to heal itself. Scientists in the Netherlands have created a bio-concrete blend with built-in bacteria that can patch up small cracks and holes in cement. Activated by water, the bacteria would eat food provided in the concrete mixture to combine calcium with oxygen and carbon dioxide to form what is essentially limestone.
Henk Jonkers, one of the scientists involved in the project, explains that water creates a threat to the stability of concrete, “Water is the culprit for concrete because it enters the cracks and it brings aggressive chemicals with it.” Since the built-in bacteria require water to begin their work, the solution is a natural fit.
In order to find bacteria that could survive in the high-pH environment of concrete, the scientists turned to the naturally high pH soda lakes in Russia and Egypt. But being able to survive in a high pH environment alone wasn’t enough. Scientists also needed to find bacteria that could lay dormant for years without dying off. The bacteria that they located fit both of these requirements. To keep the bacteria away from the food source until it is needed, the scientists formed the bacteria and food into tiny pellets, which are only activated when water touches it.
image via Wikicommons