PSI - Issue 81

Mykola Pidgurskyi et al. / Procedia Structural Integrity 81 (2026) 439–446

445

Fig. 10. Equivalent stresses around perforation openings reinforced with stiffening rings: a), b) horizontal beams without and with haunches; c), d) double pitched beams without and with haunches.

Fig. 11. Variation of maximum equivalent stresses around openings of perforation along the beam: a) horizontal beams; b) double-pitched beams

The results demonstrate that reinforcing perforation openings with stiffening rings reduces stresses around these openings, ensuring that the stresses do not exceed the material’s yield strength. Compared to analogous beams without haunches and without reinforcement, the maximum equivalent stresses around the openings are reduced as follows: for the horizontal beam without haunches with reinforcement – by a factor of 2.26, and with haunches – by a factor of 2.87; for the double-pitched beam without haunches – by a factor of 1.58, and with haunches – by a factor of 1.70. For the comparison of structural configurations, an efficiency criterion K was introduced, which accounts for the beam self weight and the maximum stresses around the perforation openings:

u

K

=

(1)

w



max 

where: σ max – maximum stresses around the perforation openings [MPa]; w – beam mass [kg]; u – conditional coefficient [MPa· kg] ( u =1·10 6 MPa· kg).