PSI - Issue 72

Vera Vujović / Procedia Structural Integrity 72 (2025) 5 – 12

8

3. Wooden piles and wooden parts of foundation Stone and oak reinforcements within the structure in stationary conditions of heat and moisture are durable, however, when exposed to frequent changes in these conditions, which occur due to frequent changes in the water level of the Drina River (operation of the HPP Višegrad and HPP Bajina Bašta), they are prone to rapid deterioration. Due to the aforementioned damage, almost all pillars/girders of the bridge can appear, as well as wood rotting. According to the assessment of previous studies made before the reconstruction of the bridge, damage is formed in the foundations that most affects the bearing capacity of the material and the supporting system. These damages appeared suddenly on the surface of the foundations, and are the result of the fall of the original waterway (thalweg), displacement due to water abrasion and partial losses. Also, an increase in biodeterioration was observed due to the flow of water through the mortar joints. The flow of water through the bridge slab can also cause biodeterioration and lead to the decomposition of the mortar joints between the stone blocks, and as a result of the expansion of the volume due to freezing of water and causes the separation of the stone blocks.

Fig. 3. Water level

Table 1. Mechanical properties of wood used for foundations

perpendicular to the fiber σemn.(Mpa)

perpendicular to the fiber E (Mpa)

parallel to fibers E (Mpa)

wood

Ɛ

ɤ (kg/m3)

TS 647 (fir)

300

10000

TS 647 (oak)

3

600

12500

TSISO9194

640-800 sert 410-570 yum.

400

8000

0,4

Jasienko

adopted

3

5000

0,4

600

Table 2.Mechanical properties of stone tufa

Tufa (sedra)

σort. (Mpa)

E (Mpa)

Ɛ ɤ (kg/m3)

experimental

9,71-30,53

1900-2242

Teymen adopted

14200-17400

15000

0,30

2000