Ukrainian Journal of Forest and Wood Science

Wood, as an ecological material, is increasingly gaining popularity. However, a decrease in the quality of wood. Applicability timber of low quality in building structures raised the question of the definition of certain indicators of strain. The results of research on determination of deformations of round wood with defects under the influence of step-by-step increasing loading are given in this article. The round wood for this research has been supplied from Kyiv region. There were studied ten control samples and samples of ten knots. Elastic deformations and deformation return after unloading were measured. Moisture of samples, diameter, average dimensions of the greatest knots were taken into account during testing. After testing the samples destroyed. The results of the study concluded that the process of deformation of wood with knots and without knots for actions in step-by-step of growing stress at compression along wood fibers of the upper limit load below the conventional boundaries of proportionality, virtually identical, and deformation of samples with knots had more numerical value and increased with an increase in the size of knots.

Pine logs, knot, deformability, loading along fibers, deformations