Using a 3D printer that works with molten glass, researchers forged LEGO-like glass bricks with a strength comparable to concrete. The bricks could have a role in circular construction in which materials are used over and over again.
“Glass as a structural material kind of breaks people’s brains a little bit,” says Michael Stern, a former MIT graduate student and researcher in both MIT’s Media Lab and Lincoln Laboratory. “We’re showing this is an opportunity to push the limits of what’s been done in architecture.”
Stern is also the founder of MIT spinoff, Evenline. That company developed a special 3D printer that can execute additive manufacturing using molten glass as its feedstock, which you can see in operation in the following video.
In printing the bricks, Stern and his team used soda-lime glass that is used in most glass-blowing studios.
The bricks have a figure-eight design which, the engineers say, allows them to be used for curved construction projects. They also contain two small pegs on the bottom that allow them to interlock, much in the same way LEGOs go together. After the bricks were printed, the team placed them in an industrial hydraulic press to see how much force they could take and found that they were almost as strong as concrete blocks. Adding an interlocking feature from aluminum on the bottom of the blocks made them even stronger.
The researchers also built a small wall using the bricks as a proof of concept.
The bricks fit neatly into the circular construction ethos in several ways. First, they are made from recycled glass. Second, after they have fulfilled their role in supporting a structure, they can be snapped apart and reconfigured into a new form. Finally, if the bricks themselves won't work in a new project, the glass can be melted down and 3D printed into a different shape.
The material joins other eco-friendly glass bricks including those made from discarded glass and recycling waste ash, as well as a set of highly insulating glass blocks made from aerogels.
“I get excited about expanding design and manufacturing spaces for challenging materials with interesting characteristics, like glass and its optical properties and recyclability,” says Kaitlyn Becker, assistant professor of mechanical engineering at MIT who helped develop the bricks. “As long as it’s not contaminated, you can recycle glass almost infinitely.”
A research paper describing the development and testing of the bricks has been published in the journal Glass Structures and Engineering.
Source: MIT
