The emergence of 3D printing has profoundly disrupted certain industries such as orthopedic medicine or aerospace. This technology is also very promising in the field of construction and civil engineering; even if 3D printing is still far from replacing conventional techniques, more and more companies are starting to use it to produce large structures, in particular because it allows large works of complex shape to be produced in very short time frames.
The prestigious MIT is also working on this theme, but with a different approach: using 3D printing to produce structural elements that can be dismantled and then reassembled sustainably, in order to build several generations of buildings with the same materials. Seduced by this approach, called ” circular construction “, engineers associated with the American institution have just unveiled a new type of ” reconfigurable masonry “, based on 3D printed recycled glass blocks.
Surprisingly strong glass bricks
These elements are the work of Evenline, a startup that spun out of MIT. In particular, it has developed a special 3D printer, called Glass 3D Printer 3. As its name suggests, it is specifically designed to work with glass. Instead of melting a filament of metal or plastic, it is fed by a furnace that melts crushed glass bottles. The molten glass can then be deposited layer by layer by the print head, building figure-8 bricks that fit together.
Intuitively, the idea might seem outlandish, given that glass has a reputation for being fragile and delicate. But under the right conditions, it can be a remarkably strong material. Evenline conducted a long series of mechanical tests that involved placing the bricks in a hydraulic press until they fractured. And the results were very encouraging; some of these glass elements were found to be able to withstand pressures comparable to those of a concrete block.
MIT, however, points out that not all bricks were treated equally; only the ” more resistant ” could compete with the king of building materials. This suggests that the deposition technique is not yet fully developed. But it still proves that the potential of glass is very real in this context.
A sustainable approach
But the real benefit of this approach, according to MIT, is its environmental sustainability. Unlike concrete, glass can be recycled more or less indefinitely, as long as care is taken to avoid contamination during melting and deposition. Once the structure reaches the end of its life cycle, it can simply be dismantled, those bricks crushed, and the process repeated to erect a new building using the same materials.
Ultimately, this technology is still far from mature. But the concept remains promising, and it will be interesting to see whether MIT and Evenline can exploit this approach in a large-scale project, possibly with different materials but maintaining this “circular construction” approach.
Source: www.journaldugeek.com
