doi: 10.52899/24141437_2026_02_159
UDK: 539.3

Assessment of the effect of slightly curved cracks on the stress-strain state of ship hull structures and welds

Самаров Е. К., Ионченкова Я. Ю.
Article language:
Citation Link: Ionchenkova YaYu, Samarov EK. Assessment of the Effect of Slightly Curved Cracks on the Stress-Strain State of Ship Hull Structures and Welds. Transactions of the Saint Petersburg State Marine Technical University. 2026;5(2):159–165. DOI: 10.52899/24141437_2026_02_159 EDN: LBDTYN

Annotation

Background: The analysis of the stress-strain state of ship hull structures and welds containing defects in the form of cracks is a critically important task for ensuring the strength and durability of marine vessels. Of particular interest are slightly curved cracks, the shape of which is closest to the actual defects that occur in structures. An accurate assessment of their effect on stress concentration in the vicinity of the crack tip is necessary for predicting the development of fracture. Aim: This work aimed to develop a mathematical model and evaluate the effect of the weak curvature of a semi-infinite crack on the local stress-strain state and stress intensity factor at the crack tip for ship hull structures and welds. Methods: The perturbation method is used, based on the expansion of the solution into an asymptotic series with respect to a small parameter characterizing the curvature of the crack. To construct corrections to the solution, the apparatus of weight functions is used, which makes it possible to obtain an integral representation for the stress intensity factors. Results: Explicit asymptotic formulas for stress intensity factors have been obtained, which show that the effect of crack curvature on the local stress-strain state is integral and is determined by the entire history of curvature changes along the crack. Conclusions: The developed algorithm makes it possible to estimate the stress-strain state in the vicinity of the tip of a weakly curved crack with the required accuracy. The results obtained can be used to refine the strength and durability criteria for ship structures in the presence of defects of complex shape. Keywords: semi-infinite weakly curved crack; stress-strain state; asymptotics of the solution in the vicinity of the angular point; stress intensity factor.

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