By Harry Bligh
A research group led by Cardiff University’s engineering department has been awarded a £4 million investment from the Engineering and Physical Sciences Research Council (EPSRC)
Over the last few years, Resilient Materials 4 Life (RM4L) project has been developing self-healing concrete in an effort to reduce the estimated £40 billion the government spends per year, repairing and maintaining infrastructure I the UK.
The RM4L group is a collaboration with University of Cambridge, University of Bradford and University of Bath, as well as industrial partners. Being pioneered at the School of Engineering at Cardiff University.
Professor Bob Lark, leading the team from Cardiff University and principle investigator on the project said: “We are confident that our research will have a significant impact on the sustainability of our infrastructure and we are very grateful to EPSRC for their vote of confidence in what we are endeavouring to do”
This new concrete advancement would have the potential to self-diagnose damage and heal without human intervention.
The team at the University of Cambridge researched at a nano and micro scale, looking at microcapsules as a way to fix tiny cracks, not visible to us, but the starting point of a larger crack. This would mean small capsules could be opened via a mechanical or chemical trigger, expelling fluid which could fill in and repair small cracks in the concrete.
The team at the University of Bath looked at a way of fixing micro cracks that can coalesce to form larger cracks which are due to de-bonding between aggregate particles and cement aggregates. They researched methods for the concrete to heal using microbial action, in other words, using calcite-precipitating bacteria embedded in concrete.
Researchers here at Cardiff University were looking on a more macro scale, at visible cracks like we often see on our roads. They took a different approach, looking at healing via crack prevention with shape memory polymers. This would use a lattice of specially designed polymers with an ability to revert to their original shape when activated. The team also looked at creating a flow network, much like a human being has blood vessels and capillaries under the skin, which bleed and clot when the skin is broken, this technology would have a brittle coating and micro channels mounted on a vascular substrate which would have the potential to fix itself if the coating was to crack.
The final research is a combination of all the groups findings, a system integration combining flow networks, shape memory polymers, microcapsules and bacteria to make a self-healing and self diagnosing concrete.
Chief executive of EPSRC, Professor Phillip Nelson, told Cardiff University: “Resilient materials 4 life has the potential to revolutionise the way our infrastructure copes with long term wear and tear and reduce costs significantly”
Could this be an end to the nationwide pot-hole epidemic?
For more information go to http://www.materials4life.org.uk/