Researchers at Delft Technical University in the Netherlands have developed a bacterial additive for concrete, the most widely used building material in the world, which could dramatically extend the life of concrete-framed buildings, and thereby save billions.
Cracking, or ‘spalling’ in traditional concrete (caused by the freeze/thaw effect of rainwater expanding and contracting inside hairline cracks in the concrete’s surface) is a major problem for the construction industry and necessitates a constant regime of repair and maintenance long after a building has been completed.
The experimental concrete contains limestone-producing bacteria, which are activated by the corrosive rainwater. These bacteria, once moist, expand to plug up the very cracks in the concrete through which the rainwater enters.
The additive would reduce the need for repair and maintenance work, while also allowing for a longer lifespan.
The system has been developed by microbiologist Henk Jonkers and concrete technologist Eric Schlangen who hope to be able to commercialise it within the next two or three years.