Researchers at Drexel University in the US are working on a new form of self-heating concrete capable of automatically melting snow and ice when temperatures are particularly low. The idea is to one day be able to build roads with this concrete to reduce the need for salting and snow removal.
This research is part of a drive to create greener, more resilient infrastructure. To achieve this, researchers have incorporated micro-capsules of phase-change materials, notably kerosene, into the conventional composition of concrete. These materials are capable of changing their physical state according to the temperature to which they are exposed. As such, they store and release heat, keeping the surface at a positive temperature sufficient to prevent it from freezing.
Initial tests have already demonstrated the concrete's ability to stay "warm" for up to 10 hours. Using cameras and thermal sensors, the researchers monitored the temperature and behaviour of several slabs.
All managed to maintain a surface temperature of between 4 and 13 degrees Celsius throughout this time, even as the air temperature dropped below 0. However, further, more detailed studies are still required to confirm the long-term viability of this technology.
It should be noted that this self-heating function not only de-ices surfaces in winter, but also accelerates the hardening process of concrete.
In addition to roads, this type of technology could one day have a significant impact on construction, improving the energy efficiency of buildings while reducing greenhouse gas emissions.
The scientists' research is published in the Journal Of Materials In Civil Engineering.
Until now, the relatively few experiments with self-heating road sections have involved installing electric cables beneath the road surface, which heat up to melt snow and ice. While this system is relatively effective, it is complicated to install over long distances. It also consumes a lot of energy and is very expensive to implement. – AFP Relaxnews