Wood can be assembled as a bi-layered cross-laminated composite, so called wood bilayers
(Rüggeberg and Burgert, 2015). Hereby, the swelling and shrinkage anisotropy enables wood
bilayers to act as hygromorphic self-shaping composites that display large deformations upon
changes in moisture content. Application at both the small-scale, e.g. as climate adaptive
actuators, and at the large-scale, e.g. as curved cross-laminated timber are possible (Grönquist
et al., 2019). However, the complex mechanical behaviour of bulk wood challenges both the
fundamental understanding of the self-shaping mechanism and the accurate shape-prediction in
function of given boundary conditions. We address these issues by the combined study of
experimental data and results from wood-specific mechanical models such as analytical and
numerical models.
Keywords: wood bilayers, hygromorphic self-shaping, cross-laminated timber (CLT)
Authors
Philippe Grönquist
ETH Zurich / Empa, Zürich, Switzerland
Falk K. Wittel
Markus Rüggeberg
Login to download the PDF