Influence of wood anisotropy on its mechanical properties in relation to the scale effect

As a construction material wood is characterized by many advantages: low density, a high degree of strength and stiffness, low thermal and electrical conductivity and chemical durability. However, it is an anisotropic material that contains structural elements of varying stiffness and strength. When moisture levels increase, it is characterized by the variability of its mechanical properties and creep resulting from rheological properties. Therefore, it is important to understand how the mechanical properties of wood vary depending on its heterogeneity, the orientation of the sample in relation to the directions of anisotropy and its natural disadvantages. The research material was obtained from the lumber of pine wood, which on the basis of the four-sided planing process was divided into 2 groups: A, B. The wood was subjected to strength tests specifying for appropriate groups of samples respectively: modulus of elasticity in static bending - group A-B, static bending strength - group A-B. The influence of wood anisotropy on the elasticity and strength properties of wood was demonstrated, this results from the variability of the wood element orientation and load direction in relation to the main directions of anisotropy.