PSI - Issue 81

Oleksiy Petrenko et al. / Procedia Structural Integrity 81 (2026) 292–296

295

a

b

Н, Дж / см2

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

0,92

0,81

0,73

0,45

0

1

2

3

4

5

6

t, роки

Fig. 2. Evaluation of wood hardness changes in production pallets during operational use: a – testing; b – dependence of hardness on the terms of operation.

4. Conclusions 1. The hardness of the manufactured technological pallet wood, untreated with protective agents, at a moisture content of 8…14% was determined by the Pevzof method. 2. It has been established that the hardness of wood in the radial section is 0.96 J/cm 2 , in the tangential section – 0.88 J/cm 2 . 3. Given the chaotic orientation of individual boards in the pallet, and sometimes the impossibility of determining a specific orientation of the working surface layer, the integral value of hardness has been accepted as the arithmetic mean of the radial and tangential values – 0.92 J/cm². 4. According to the analytical and chronometric study of the operating mode, it has been established that during one year of operation, the technological pallet undergoes 250 production cycles. 5. Based on the results of wood testing for production pallets after 3, 6, 12 months, and 2, 3, 4, and 5 years of operation, a dependence of hardness on the duration of operation has been established, which has three characteristic sections: 1) a decrease in hardness during the first three months; 2) a partial increase in hardness during the next nine months; 3) a gradual decrease in hardness during the next four years of operation. References Albrektas, D., Juciene, M., Dobilaite, V., 2020. The influence of thermal modification on the resistance to water impact properties and strength of wood used in outdoor conditions. Wood research 65(3), 353-364. 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. Andor, K., Bellovics, B., 2020. Analysis of modulus of elasticity of spruce beams under bending with and without fibre reinforcement. Wood research 65(1), 101 110. Anshari, B., Guan, Z. W., Wang, Q. Y., 2017. Modelling of Glulam beams pre-stressed by compressed wood. Composite Structures 165, 160 – 170. Bojok, О., Vintoniv, І., 1992. Wood science with the basics of forest commodity science. Kyiv: Publishing by Scientific thoug ht. . 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. Donadon, B.F., Mascia, N.T., Vilela, R., Trautwein, L.M., 2020. Experimental investigation of Glued-Laminated wood beams with Vectran-FRP reinforcement. Engineering Structures 202, 109818. Doyle, J., Walker, J.C., 2007. Indentation Hardness of Wood. Wood and Fiber Science 17, 369-376. DSTU EN 335-1:2010. Durability of wood and wood products. Determination of use classes. Part 1: General.Kyiv: Ukrarchbudinform. DSTU EN 335-2:2010. Durability of wood and wood-based products. Determination of use classes. Part 2: Application to solid wood. Kyiv: Ukrarchbudinform. Fojtik, R., 2019. Moisture content analysis of wooden bridges. Wood research 64(3), 529-536. 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., 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.