Issue 75

D. I. Vichuzhanin et alii, Fracture and Structural Integrity, 75 (2026) 220-237; DOI: 10.3221/IGF-ESIS.75.16

pitch  of the line connecting the spherical radii. Specimens of three dimension types were made for testing: 1) 80   º. Figs. 17 a and 17 b show photographs of dimension type 1 specimens before and after testing as an example. Fig. 17 c shows the finite-element model used to analyze the stress-strain state in the course of testing. The front end face of the model corresponds to the symmetry plane at the half-width of the specimen. The finite element models of the specimens have the following characteristics. 2 R  mm, 2 S  mm, 30   º; 2) 3 R  mm, 2.5 S  mm, 50   º; 3) 2 R  mm, 5 S  mm,

Type I specimens: the number of finite elements is 5210 and the element size is 0.3 mm. Type II specimens: the number of finite elements is 5160 and the element size is 0.3 mm. Type III specimens: the number of finite elements is 6840 and the element size is 0.3 mm.

(a)

(b)

(c) (d) Figure 17: The oblique dog-bone-shaped specimen of dimension type 1: photographs of the specimen before (a) and after (b) testing; the 3D finite-element model ( с ); cross-sectional distribution of eq  at fracture (d) (reinforced epoxy resin, room temperature) .

Figure 18: The behavior of k during the testing of the oblique dog-bone-shaped specimen of dimension type 1 (reinforced epoxy resin, room temperature).

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