Zurich – Researchers in Zurich are making the case for using earth as a building material. And not just any earth, but specifically material excavated from construction sites. This would save both resources and energy, and the researchers are now investigating new building techniques to achieve this.
During construction, excavated material is normally
transported away in a lorry and tonnes of sand, gravel and cement
are delivered in its place. In the future, this excavation material
– the inorganic part of the soil – should be used as a building
material. This is the aim of researchers at the Federal Institute
of Technology (ETH) in Zurich.
Earthen construction is actually one of the oldest building
techniques in the world, but it is hardly used now, particularly in
modern cities. If greater use were made of the excavation material
in construction, it would short-circuit this supply chain, spare
sand and gravel resources and save energy and CO2.
There are other benefits: using earth as plaster can also help
naturally regulate air humidity and make for a significantly more
comfortable indoor climate, writes ETH Zurich. And it is not
just suitable as a replacement for structural building materials
like concrete – it should in fact be seen as an alternative for
building services technology.
ETH researchers are now working to revolutionize old building
techniques to ensure that earth can be used for building in the
modern world. The Federal Laboratories for Materials Science and
Technology (Empa) is developing mud plasters
with aerogels to further improve the humidity-regulating properties
of earth. And at ETH Zurich, researchers are working on a liquid
earth that can be poured into formworks in the same way as
conventional concrete.
An exhibition opens on 30 October at
ETH Zurich that will show the potential of excavation material in
construction.