Smart paint detects tiny faults in structures such as bridges

The paint is formed using fly ash and highly aligned carbon nanotubes, which are capable of carrying an electrical current.

David McGahon, a researcher on the project who initiated the work as part of his PhD, said: ‘When these carbon nanotubes start to bend, the conductivity in them will change.’

The bending is detected by electrodes incorporated within the structure and therefore any significant change in the flow of electrical current can be interpreted as a sign of a structural defect.

When the paint is mixed, it has a cement-like property, which makes it particularly useful in harsh environments.

‘The electrodes will be attached to a small battery and small wireless transmitters placed throughout the structure,’ said McGahon. ‘There will be a master transmitter as well that will receive and communicate the whole structure’s responses.’

The wireless communication nodes will be powered in part by a battery but are also expected to rely on energy-harvesting methods where possible.