US researchers working with SHoP Architects have created a potential alternative to steel and concrete as a structural floor material: recyclable panels made entirely from bioplastic and wood flour.
According to the team, the SM2ART Nfloor cassette panel is better for the environment and quicker to manufacture than similar steel-and-concrete elements, which are typically used in multi-storey buildings.
The researchers began work on the cassette following a prompt from SHoP Architects to explore the potential of bio-based materials and additive manufacturing for mass-produced floor panels.
The SM2ART Nfloor cassette is 3D printed from a bioplastic and wood waste mixture
"We saw the precedent in the aerospace industry, where they introduce new technologies within small parts and expand outward to the whole," SHoP principal John Cerone told Dezeen.
"We applied that principle by isolating a building system product — a light-gauge steel floor cassette assembly — from an existing supply-chain partner to benchmark its replacement with a single solid-state, printed, bio-based part."
Strength from combining materials
ORNL and UMaine made the panels using polylatic acid (PLA), a bioplastic derived from corn residue, which they mixed with wood flour made from lumber processing waste.
According to ORNL researcher Katie Copenhaver, the floor panel's strength comes from the combination of these two materials as well as its geometric shape, which distributes load to its outer edges, where it would rest within a building's steel framework.
"Adding wood flour to the PLA increases its stiffness significantly," said Copenhaver, with stiffness being key to the overall performance.
"What we can't achieve with material properties alone, we can account for with structural design," she continued. "A flat plate of steel may suffice for something and couldn't be replaced with the same geometry of PLA, but a PLA piece could potentially be designed that could also do the job."
