PSI - Issue 59

Mykola Roshchuk et al. / Procedia Structural Integrity 59 (2024) 718–723 Mykola Roshchuk et al. / Structural Integrity Procedia 00 (2019) 000 – 000

721

4

a

b

Figure 2. Diagram of deformation of spruce wood soaked: (a) in river water; (b) in sea water.

It was experimentally established that the influence of an active aqueous environment significantly reduces the strength parameters of wood and increases deformability (Table 2, Fig. 2a,b). Therefore, the ultimate strength of the investigated wood species decreased by 1.87-2.44 times when soaked in river water as compared to the standard moisture content of 12%; for soaking in sea water, it decreased by 1.98-2.61 times. At the same time, the elasticity modulus decreased by 1.23-1.56 times when soaked in river water and by 1.37-1.65 times when soaked in sea water. Critical deformations increased by 1.14-1.28 times when soaked in river water and by 1.18-1.33 times when soaked in sea water.

Table 2 – Results of experimental studies. Wood species Number of samples

Ultimate strength f c,0,d, , МРа

Elasticity modulus Е , MPa

Critical deformations u c,0,d

At a standard moisture content of 12%

Spruce

6 6 6 6 6 6 6 6 6

42.9 46.0 60.2 17.6 24.5 27.0 16.4 23.2 23.8

13900 12600 14200

0.00439 0.00503 0.00652 0.00563 0.00585 0.00742 0.00586 0.00601 0.00770

Pine Oak

Soaked in river water

Spruce

8900 9700

Pine Oak

11500

Soaked in sea water

Spruce

8400 9200

Pine Oak

10100

It was experimentally established that the influence of an active aqueous environment significantly reduces the strength parameters of wood and increases deformability (Table 2, Fig. 2,3). Therefore, the ultimate strength of the investigated wood species decreased by 1.87-2.44 times when soaked in river water as compared to the standard moisture content of 12%; for soaking in sea water, it decreased by 1.98-2.61 times. At the same time, the elasticity modulus decreased by 1.23-1.56 times when soaked in river water and by 1.37-1.65 times when soaked in sea water. Critical deformations increased by 1.14-1.28 times when soaked in river water and by 1.18-1.33 times when soaked in sea water.