A numerical limit analysis approach for predicting strength of clear wood

The main goal of this work has been the development of a new approach to understand failure mechanisms and to predict effective strength properties of clear wood. These properties are strongly influenced by the complex cellular and layered material system of wood. The application of conventional numerical methods to determine strength properties of these microstructures can be very inefficient and not always lead to satisfying results. For this reason, numerical limit analysis approaches were further developed and applied for the first time to wood, replacing conventional methods successfully at certain scales of observation in a multiscale concept for strength predictions. The comparison of numerically-obtained failure surfaces for clear wood with the experimental data from biaxial tests showed very good agreement. Due to its efficiency and simplicity, this method could represent an interesting alternative for predicting strength of wood and wood-based products.