Study of the Influence of Pine Wood Shelf Life on Endurance under Compression along the Grains

Abstract

Purpose of research. Study of the influence of pine wood shelf life on endurance under compression along the grains, as well as grounds for results obtained. Wood is anisotropic, depending on the grains, the mechanical and physical properties of the material differ greatly. Methods Wood is anisatropic, the change in its endurance depends not only on conditions, shelf life, moisture, but also on the direction of the grains in the timber. However, the relevance of using this material still remains unchanged. The tests were carried out on a press of the UM-5 type. After carrying out the compression test, moisture tests were performed and the test results of the specimens were reported at 12% moisture. Untested samples were stored from 1981 to 2019 in the laboratory of the Department of Industrial and Civil Engineering at South-West University. In 2019, the stored samples were prepared for testing and tested. Results. To obtain substantiated data on the influence of wood shelf life on endurance, an experiment was carried out with the bars that had undergone a 39-year wait in the laboratory of the Department of Industrial and Civil Engineering. From among the samples, 16 samples were selected, which were tested for short-term compression load along the grains. For these samples diagrams “Load-displacement” were recorded on the press UM-5. The experiment showed two types of sample destruction which led to the corresponding conclusion. Conclusion. The strength characteristics revealed as a result of experiments from core and sapwood of pine on samples 20x20x30 in 1981 and in 2020 significantly differed from normal ones, this was influenced by a relatively small number of samples.