Accuracy of regular wood cell structure model

• The dependency of rigidity of wood on geometric and material parameters was studied.
• The studied feature was compared to a regular cell structure by simulation.
• Thickness variation was found to have the largest effect on the rigidity.
• Results give insight what features to include when modeling cellular structures.

The material rigidity of a cellular structure depends on numerous mechanical and geometrical parameters. This dependency was studied here by simulation on a micromechanical model. The rigidities of different cases were compared to the rigidity of the deterministic or exact case to find the effect of different parameters. The deterministic case was based on the mean values, whereas the geometrically exact model was based on the scanned image, and the different cases consider the variation in the thickness of the cell wall, geometry, and Young’s modulus of the cell wall. The study concentrated on the cellular structure of earlywood in Norway spruce. The starting point was a set of earlywood structure images in an RT plane, from which geometry of the mid-cell wall and cell wall were extracted and used as the exact geometry. Geometric analysis in the statistical sense based on the cell wall lengths and thicknesses provided a statistical model for the cell’s geometry.