Due to the new technology being developed by the European Research Project, the self-healing materials, the tunnels, bridges and other civil engineering structures can be much safer.
Elke Gruyaert, one of the team of Engineers working on the project at Ghent University in Belgium, told us about the mechanism of the self-healing:
He told us that there is a polymer that is hyper-retentive for water filling the concrete material, they are interact with the water that comes through the cracks that happen in the concrete and swell filling the gaps caused by these cracks preventing more water absorbtion.
The mix of the concrete have the polymers mixed into them. When they dry up, they are tested by the researchers by cracking it and see how they react to this action. And they measure it on its strength, water isolation and the mechanical performance.
Another member of the research team at Ghent University, Brenda Debbaut (Industrial Engineer) told us that this mechanism will prevent further growth of small cracks, which causes the structure to fail and fall down.
In case of tunnels and bridges, even a tiny crack can be a threat, and the scientists working on this project confirm that this material will be lifesaving as they are able to bear the forceful and mechanical loads.
Technical Manager of the Magnel laboratory for Concrete Research, Nele de Belie, says that the waterproofness is the main factor for this material saying that you just don’t need the concrete to be strong or durable but you need it also to be impermeable to maintain the previously mentioned factors.
Other than polymers there are some biological agents used by the research team in Delft University, Netherlands. These agents are: Bacteria.
A Biologist at Delft University, Henk Jokners says that they have isolated non-pathogenic bacteria, for either humans or the environment, from our planet that have conditions of solidness like concrete with alkaline pH which are like the ones of the concrete.
The mechanism of their action is that when they combine with water that leak from the cracks and create Calcium Carbonate which fill in the crack. This technique is currently under test by the scientists for their waterproofness and strength.
Eirini Tziviloglou, a civil engineer at Delft University of Technology says that they are testing the penetration of water and comparing the results between before and after the self-repair process.
The researchers’ goal is to cover about 70% of concrete-made tunnels and bridges over Europe with this new technology.
Says Nele de Belie that the cost will be high initially then the maintenance cost will be much less than the original, which give it an economical benefit.
These materials are a still under testing but in the future they may become crucial in the market.