Improvements in printability and mechanical measures incorporating plant-based material in commercial 3D-printable materials may lead to more resilient and eco-friendly construction.
This news comes from the University of Virginia School of Engineering’s Professor Osman Ozbulut ahead of research to be published in September 2024 in the journal Cement and Concrete Composites.
His team explored how cellulose nanofibrils (CNF) which are renewable, low impact and made from wood pulp, could amplify the benefits of 3D-printed concrete technology offering a slew of benefits such as rapid and precise construction, with the possibly of using recycled materials. In addition, reduced labor costs and less waste while enabling intricate designs that would be difficult to deliver by traditional methods.
Like other plant-fiber derivatives, CNF, shows strong potential as an additive to improve the rheology and mechanical strength of these composites.
“We’re dealing with contradictory objectives,” Professor Ozbulut said. “The mixture has to flow well for smooth fabrication, but harden into a stable material with critical properties, such as good mechanical strength, interlayer bonding and low thermal conductivity.”
Experimenting with varying amounts of CNF additive, the research team found that adding at least 0.3% CNF significantly improved flow performance. Microscopic analysis of the hardened samples revealed better material bonding and structural integrity. In further testing, CNF-enhanced 3D-printed components also stood up to pulling, bending and compression.
Image: Team member Ugur Kilic observing the 3D printing.
About the author
Desi Corbett
Desi is the Editor of Concrete in Australia and at the helm of our magazine for 8 years. She was behind the Institute's weekly news bulletins from 2016-2021 and is now writing our focused news items. Desi has been an engineering news and features journalist/editor across all disciplines since 2013 - part of a 30-year career writing for a wide range of industries.