A bacteria strain that produces a special glue that hardens to the same strength as concrete was recently developed by a team of nine students at Newcastle University in England.
Dubbed "BacillaFilla," the microbes only germinate once they sense the specific pH of concrete, and the clumping of other bacterial cells tells them when they have hit the bottom of the crack.
Once there, the clumping triggers the bacteria to split into three cell types: some produce calcium carbonate crystals, a portion act as reinforcing fibers, and others produce a glue that binds the cells together and fills the gaps in the concrete. BacillaFilla eventually hardens to the same strength as concrete.
BacillaFilla is not a threat to the environment, the team says, because the microbes carry a self-destruct gene that makes them unable to survive in the environment.
"Around 5% of all man-made carbon dioxide emissions are from the production of concrete, making it a significant contributor to global warming," says joint project instructor Jennifer Hallinan. "Finding a way of prolonging the lifespan of existing structures means we could reduce this environmental impact and work towards a more sustainable solution. This could be particularly useful in earthquake zones, where hundreds of buildings have to be flattened because there is currently no easy way of repairing the cracks and making them structurally sound."
The project is fueling further research at Newcastle University.