Influence of morphology on the effective hygro-elastic properties of softwood (spruce) and hardwood (balsa)

Abstract Wood materials are characterized by complex, hierarchical material structures spanning across various length scales. The present work aims at establishing a relation between the hygro-elastic properties mesoscopic cellular level and effective response macroscopic level, both for softwood (spruce) hardwood (balsa). particular aim is to explore influence on under variations in meso-scale morphology. multi-scale framework applied this purpose uses method of asymptotic homogenization, which allows accurately efficiently obtain heterogeneous complex meso-structural geometries. model considered based periodic, two-dimensional statistically representative volume element that generated spatial repetition tracheid cells. cells modeled as hexagonal elements certain geometrical irregularity. meso-structure consists region composed fibers with large vessels embedded, connected ray constructed elements, similar tracheids. rays represented quadrilateral oriented along radial direction, whereby different arrangements considered, i.e., either regularly stacked or organized staggered configuration. interface fiber regions may also be regular arrangement. models discretized means plane-strain, finite models, describe wood radial–tangential plane. For softwood, sensitivity elastic hygro-expansive explored function irregularity hardwood, studied variation cell arrangement, type regions, vessel fraction. modeling results agree well obtained from other numerical homogenization studies show reasonable agreement experimental data taken literature.