Invisible armies of microscopic bacteria could help create “self-healing” buildings resistant to damage.
With maintenance and repair bills rising and “substantial” interest from industry, engineers from Cardiff University said bacteria’s unique properties could make it the perfect protection against cracks and other deterioration.
A two-year project at the university is exploring how damage could trigger the release of bacteria and a range of “helper” chemicals, allowing buildings to repair autonomously. The microorganisms can produce mineral deposits such as calcium carbonate – a key component in rocks and other masonry materials – when mixed with precursor chemicals.
The study’s principal investigator, Dr Mike Harbottle, said bacteria could be “entombed” within spores of the mineral, alongside the precursor chemical. “When damage occurs to the masonry, the deposits within the mineral are also damaged, exposing both the bacteria and the chemicals, which react with each other again to produce even more mineral, thus healing the damage.”
Buildings are constantly damaged by weathering, said research fellow Magdalini Theodoridou. “These could be physical, chemical or biological changes which can all slowly attack the masonry structure,” she added. “Over time, usually many years, this damage builds up until fractures arise. Whilst these may not compromise the integrity of a structure immediately, if allowed to develop then damage may become critical.”
During the project, the team will develop ways of introducing the substances into masonry, whether during the material’s production or after buildings have gone up. One possible solution could be a liquid containing the bacteria and other chemicals, designed to be sprayed on to buildings.
The research is funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Individual Fellowship scheme.
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.
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