Wood that shapes itself

Wood is a renewable resource and a popular, sustainable construction material. Complex architectural designs featuring curved or twisted structures, however, pose increasing challenges for the wood construction sector. Reshaping wood currently utilises large machines that consume substantial amounts of energy to press the building elements into the required shapes.

In a study recently published in Science Advances, researchers from ETH Zurich and Empa presented a process that has the potential to replace these inefficient mechanical reshaping processes. In collaboration with colleagues from the University of Stuttgart, they have developed an approach that makes solid wooden construction elements bend themselves into a pre-set shape without the use of external mechanical force.

Once a bilayer panel has reached its target shape, it can be glued together with similarly curved panels in a process called lamination. This allows the research team to obtain the required material thicknesses for use as cross-laminated timber, which always consists of multiple layers. A wooden component produced in this manner remains dimensionally stable even in fluctuating humidity.

“Our approach enables a wide range of shapes and curvature radii. The concept of programming wood opens up new architectural possibilities for this regionally available, renewable construction material,” says Philippe Grönquist, the lead author of the study who works at both institutions and has dedicated his doctoral thesis to this topic. The researchers have submitted a patent application for their method.