Use of concrete as building materials might soon become obsolete as scientists at Texas A&M University have developed a sustainable 3D printing technology that uses local soil for the construction of buildings, according to a report by The Guardian
In a virtual meeting and expo held by the American Chemical Society on August 20, Sarbajit Banerjee, the project’s principal investigator, said that the environmental impact of the construction industry is a big issue.
"Some researchers have turned to additive manufacturing, or building structures layer by layer, which is often done with a 3D printer. That advance has begun to transform this sector in terms of reducing waste, but the materials used in the process need to be sustainable as well.”
Describing the process, researchers said that they collected soil samples from a colleague’s backyard and tailored the material with an environment-friendly additive that bound the soil. The clayey component of the soil which can easily be moulded.
The researchers also built a chemistry “toolkit” that would transform any type of soil into printable building materials.
To increase the material’s load-bearing capacity and strengthen the clay mixture, the researchers ‘zippered’ microscopic layers on its surface to stop the absorption of water and expansion. According to the researchers, the strengthened material could hold twice as much weight as the unmodified clay.
“Our thought was to turn the clock back and find a way to adapt material from our own backyards as a potential replacement for concrete,” said Aayushi Bajpayee, a graduate student who was part of the project.
This research is not to replace concrete but allow construction in difficult environments, Banerjee said.
“We have worked on addressing the problem of building all-weather roads in the subarctic. [The technology] could one day be used beyond Earth, to create settlements on the moon or even Mars.”
According to the International Energy Agency, the production of concrete accounts for 7% carbon dioxide emissions.