PSI - Issue 81

Mykola Roshchuk et al. / Procedia Structural Integrity 81 (2026) 499–503

502

Fig. 3. Failure mode of the test beams

4. Conclusions 1. The main features of the manufacturing process of solid-section timber beams, their immersion, and the testing methodology are presented. 2. Experimental investigations of bending elements after long-term wetting under a single short-term load were performed. 3. Based on the experimental results, the load-bearing capacity of both immersed and non-immersed test beams was determined. 4. It was established that after 180 days of immersion in freshwater, the load-bearing capacity of solid-section pine beams decreased by a factor of 1.76, and that of spruce beams by a factor of 1.62, compared to specimens with a moisture content of 12%. After exposure to saline water, the reduction amounted to a factor of 1.58 for pine and 1.84 for spruce. References Aleksiievets, V., Gomon, S., Aleksiievets, I., Homon, S., Ivaniuk, A., Zadorozhnikova, I., Bandura, I., 2024. Influence of thicknesses of outer and middle elements on the performance of nail connections. Procedia Structural Integrity 59, 710-717. Cragg, S. M., 1996. Timber in the marine environment. Timber Trades Journal 376, 26-28. Crossman, M., Simm, J., Crossman, M., 2024. Manual on the use of timber in coastal and river engineering. London: Thomas Telford. Datsiuk, V., Homon, S., Gomon, S., Dovbenko, V., Petrenko, O., Parfentyeva, I., Romaniuk, M., 2024. Effect of long-term operation on the strength properties of pine wood. Procedia Structural Integrity 59, 583-587. DBN B.2.6-161, 2017. Constructions of houses and buildings. Wooden constructions. Main provisions. Kyiv: Ukrarchbudinform. DSTU EN 380-2008 (2010). Structural timber. General guidelines for static load testing methods. Kyiv: Ukrarchbudinform. DSTU 4922:2008 (2012). Timber and sawn wood products. Methods for determination of moisture content. Kyiv: Ukrarchbudinform. DSTU EN 336 – 2003 (2004). Structural timber of coniferous species and poplar. Dimensions. Permissible deviations. Kyiv: Ukrarchbudinform. Eurocode 5, 2004. Design of timber structures. Part 1.1. General rules and rules for buildings, 124. Evans, P. D., Banks, W. B., 1988. Degradation of wood surfaces by water changes in mechanical properties of thin wood strips. Holz als Roh-und Werkstoff 46(11), 427-435. Fojtik, R., 2019. Moisture content analysis of wooden bridges. Wood research 64(3), 529-536. Gerhards C.C., 1982. Effect of moisture content and temperature on the mechanical properties of wood: an analysis of immediate effects. Wood and Fiber 14(1), 4 – 36. Gomon, P., Gomon, S.S., Pavluk, A., Homon, S., Chapiuk, O., Melnyk, Yu., 2023. Innovative method for calculating deflections of wooden beams based on the moment-curvature graph. Procedia Structural Integrity 48, 195-200. Gomon, S., Gomon, P., Korniychuck,O., Homon, S., Dovbenko, T., Kulakovskyi, L., Boyarska, I., 2022. Fundamentals of calculation of elements from solid and glued timber with repeated oblique transverse bending, taking into account the criterion of deformation. Acta Facultatis Xylologiae Zvolen 64(2), 37-47. Gomon,S., Homon,S., Pavluk, A., Matviiuk, O., Sasiuk, Z., Puhach,Yu., Svyrydiuk, O., 2024. Hypotheses and prerequisites for modelling the stress-strain state of wooden element normal cross-section using the deformation calculation method. Procedia Structural Integrity 59, 559-565. Gong, L., Zhang, Q., Liang, H., Ren, S., Wang, G., 2019. Mechanical properties and microstructure of Zabelia biflora. Wood research 64(3), 423-436. Heitner, C., Dimmel, D., Schmidt, J., 2010. Lignins and Lignans: Advances in Chemistry. CRC Press: Boca Raton, FL, USA, 2010. Homon, S., Dovbenko, T., Savitskiy, V., Khoruzhyi, M., Petrenko, O., Sunak, P., Kysliuk, D.Y., 2024. Influence of natural composite materials on mechanical properties of wood. Procedia Structural Integrity 59, P. 595-600. Homon, S., Gomon, P., Gomon, S., Pavluk, A., Karavan, B., Petrenko, O., Homon, O., Chapiuk, O., 2025. Determination of main strength and deformation parameters of complete diagrams of glue-laminated wood deformation. Procedia Structural Integrity 72, 301-307. Homon,S., Gomon, P., Gomon,S., Litnitskyi,S., Boyarska,I., Chapiuk,O., Chornomaz, N., 2024. Study of the mechanical properties of coniferous wood of different ages at standard humidity. Procedia Structural Integrity 59, 545-550. Homon, S., Litnitskyi, S., Gomon, P., Kulakovskyi, L., Kutsyna, I., 2023. Methods for determining the critical deformations of wood at various moisture. Scientific