Engineers develop printed bricks from construction waste

Engineers behind the three-year DigiMat project aim to develop and demonstrate an eco-friendly cement mix, created from construction waste, that can be easily printed into new, tight interlocking bricks for use in new buildings.

Project lead Dr Seyed Ghaffar, said: “Demonstration projects built over the past few years have shown both the viability and potentials of 3D printing technologies, however, these projects have used conventional raw materials in their concrete feedstock.

“The use of recycled waste driven secondary raw materials to replace virgin aggregates for 3D printing of a building block has not yet been done, but we hope to demonstrate it with this project.”

DigiMat hopes to reduce the construction industry’s reliance on cement by offering a clean and affordable solution that reuses materials recycled from other buildings.

The team plans to demonstrate their technology by printing out a series of 50cm x 50cm recycled bricks which will be slotted together to form an interlocked wall in a similar fashion to one built from Lego.

‘Decrease the CO2 footprint’

“Nearly half of all materials extracted from Earth annually are used in concrete, and extraction of construction virgin aggregates is the main part of the global non-metallic mineral consumption,” said Dr Ghaffar, who heads the Additive Manufacturing Technology in Construction (AMTC) research group.

“Our objective is to decrease the CO2 footprint of printed products against traditional virgin concrete and cementitious mortars, through the development of printable mixtures that will use up to 100% recycled aggregates.”