PSI - Issue 81

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

501

Fig. 2. Testing of a solid-section bending element.

3. Results and discussion Based on the conducted full-scale experimental studies, the performance characteristics were identified and the load-bearing capacity values of both wetted and non-immersed solid-section bending elements were determined for all tested specimens (Table 1). The load-bearing capacity values of the wetted and non-immersed solid-section test beams are given in Table 2. The reported indicators were averaged.

Table 2. Load-bearing capacity values of wetted and non-immersed solid-section test beams. Timber species Beam cross section, mm Immersion duration, days Timber moisture content, % Loading type

Load-bearing capacity, kN

Without wetting

Pine

50x80x1650 50x80x1650

- -

12 12

Single short-term Single short-term

14.1 10.7

Spruce

Wetting in freshwater environment

Pine

50x80x1650 50x80x1650

180 180

>30 >30

Single short-term Single short-term

8.0 6.6

Spruce

Wetting in marine environment

Pine

50x80x1650 50x80x1650

180 180

>30 >30

Single short-term Single short-term

8.9 5.8

Spruce

Based on the experimental results (Table 2), it was established that the load-bearing capacity of non-impregnated pine beams was 14.1 kN, while for spruce beams this value was 10.7 kN. After conditioning in freshwater, a reduction in load-bearing capacity was observed to 8.0 kN for pine beams and to 6.6 kN for spruce beams. Under exposure to saline water, the corresponding load bearing capacities were 8.9 kN for pine and 5.8 kN for spruce. Thus, 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 normative 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. The failure mode of a spruce timber test beam after immersion in saline water is shown in Fig. 3.