A microstructure-based multisurface failure criterion for the description of brittle and ductile failure mechanisms of clear-wood

Previously proposed failure criteria for wooden cells are now linked to unit cells at the annual ring scale. Extensive investigation of load combinations allow the identification and classification of the main failure mechanisms of clear-wood. Based on these findings, a multisurface failure criterion is formulated, indicating brittle as well as ductile failure mechanisms and giving interesting insight into the failure behavior. A new algorithm is presented, which enables the simultaneous description of plastic failure and cracking within numerical simulations. Finally, the failure criterion is validated for biaxial experiments and applied to a timber engineering example.