A Roman solution to Raac’s ruin – is self-healing concrete the answer?

After recent building failures, researchers are looking to ancient materials for inspiration in creating more durable materials that repair themselves using glue or even bacteria

Concrete research gets caricatured as the epitome of dull - until the roof falls in. The dangerous state of many British schools built partly from reinforced autoclaved aerated concrete (Raac) has dominated headlines, alarmed parents and embarrassed the government, leading to emergency closures just as the new school term began. The crisis highlights that, however boring concrete might seem, our civilisation almost literally stands or falls on it.

Far from being prosaic, concrete is a hi-tech substance at the forefront of materials research. One dream is to make concrete self-healing: able to repair its own cracks automatically. And modern research is drawing inspiration from an ancient source - the unassailable concrete of the monuments, aqueducts and harbours built by the Romans more than 2,000 years ago. Couple this with ingenious ploys such as entombing live, crack-sealing bacteria inside concrete, and research in this area could transform the way we build.