Experimental concrete that patches up cracks by itself is to undergo outdoor testing.
The concrete contains limestone-producing bacteria, which are activated by corrosive rainwater working its way into the structure.
The new material could potentially increase the service life of the concrete – with considerable cost savings as a result.
It is the brainchild of microbiologist Henk Jonkers and concrete technologist Eric Schlangen.
If all goes well, Dr Jonkers says they could start the process of commercialising the system in 2-3 years.
Concrete is the world’s most widely used building material. But it is prone to cracks, which means that structures need to be substantially reinforced with steel.
“Micro-cracks” are an expected part of the hardening process and do not directly cause strength loss. Fractures with a width of about 0.2mm are allowed under norms used by the concrete industry.
But over time, water – along with aggressive chemicals in it – gets into these cracks and corrodes the concrete.
- Key test for re-healable concrete (bbc.co.uk)
- Time to heal: The materials that repair themselves (oddonion.com)