Assessment of strength parameters of beech plywood in terms of failure criteria. The failure state in a composite layer being in the complex state of stress is defmed using the so-called material failure theories. They describe the yield surface of the material, for which the limit of linear elasticity is determined. Failure theories formulated for anisotropic materials are more complex. The paper presents the results of research on strength and deformation of the beech veneer during tension loading in relation to slope of grain. Results of the performed investigations were presented in the form of graphs end figures.
Numerical and analytical analysis of the stress-strain relations to extended beech plywood. The study presents a theoretical and numerical analysis of problems connected with the determination of strength parameters in multilayer beech plywood with varied layer configurations. Analytical calculations were performed in accordance with the classical theory of thin plates lamination in view of the theory of elasticity taking into consideration the Kirchhoff-Love hypothesis. The analyses focused on models of composite layers in plane stress. Values of components of transformed stiffness matrices were estimated theoretically together with those of flexibility in the axial and non-axial configurations of individual laminate layers. A verification was made of analytical calculation results with computer simulation results made on numerical models using the finite element method (FEM). Results of investigations are presented in the form of tables, graphs and graphic visualization of FEM calculations.