What is Self-Healing Concrete?
In the future, damaged concrete could heal itself according to engineers at the University of Cambridge. That would mean billions saved around the globe in infrastructure maintenance every year. Fewer road works and closures would also boost efficiency and productivity in other areas according to industry experts. Let’s take a look at how self-healing concrete could revolutionise the construction industry.
How does it work?
With an investment of 4.9 million pounds from the Engineering and Physical Sciences Research Council (EPSRC), full-scale trials of self-healing concrete have begun in the UK. A team of expert engineers at the University of Cambridge is perfecting a technique whereby microcapsules are created within the concrete matrix.
Within these capsules are healing agents that are capable of forming concrete when cracks appear. As cracks form and widen, the microcapsules break and release their payloads and this reacts with the water and oxygen present to heal the crack as it develops.
As it happens, there are actually two factions developing self-healing concrete in the world, with one in the UK and another in the US. The techniques each team is using, however, are remarkably different.
How does US self-healing concrete work?
Professors from Binghamton University, New York, are using fungi in their research. Pared down to the basics, the New York scientists are mixing dormant spores of a specific type of fungi into the concrete matrix along with the nutrients needed for it to grow.
Once set, the concrete is cracked under lab conditions. Water and oxygen make its way into the cracks and the spores germinate. This will set off a chain reaction whereby the spores encourage the formation of calcium carbonate, and it’s this chemical compound that gives the concrete its healing properties.
Self-healing concrete today
The realities of self-healing concrete in today’s market are that it would be prohibitively expensive for a majority of projects. On average, a cubic metre of self-healing concrete would cost £25.00 more than standard concrete. For large scale projects, this simply isn’t feasible in most cases. For smaller projects and domestic work, the technology isn’t ready and the industry isn’t ready for small scale production of self-healing concrete. However, it is seemingly a tomorrow world that isn’t very far away at all.