PSI - Issue 59

Svyatoslav Gomon et al. / Procedia Structural Integrity 59 (2024) 559–565 Svyatoslav Gomon et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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As is known, the resistance moment W is the derivative of the area, and its value is determined when the neutral force line coincides with the area’s centre of gravity. However, the neutral line shifts with the onset of loading, as indicated by the researchers (Sobczak-Piastka et al. (2023), Betts et al. (2010), Corradi et al. (2017), Levis et al. (2022); Pavluk et al. (2023)).

Fig. 1. Optimized real (full) diagrams of deformation along the wood fibers under compression and tension.

However, this resistance moment is still used in the load-bearing capacity calculations according to current standards (Eurocode 5:2004, DBN B.2.6-161:2017; NDS:2018). This leads to obtaining fictitious results. Moreover, in the compressed zone, a fold is formed (Fig. 2), which is difficult to detect during the instantaneous destruction of the wooden bending element (Gomon et al. (2019)).

a

b

Fig. 2. Formation of folds in a compressed zone: (a) in one zone; (b) in another zone.

To address this limitation, it is necessary to calculate the cross-sections of wooden bending elements using the deformation method (Gomon (2019)). This work aims to propose hypotheses and prerequisites for modelling the stress-strain state of the normal cross-section of wooden elements using the deformation calculation method.