PSI - Issue 36

Ivan Pidgurskyi et al. / Procedia Structural Integrity 36 (2022) 171–176 Ivan Pidgurskyi, Mykola Pidgurskyi, Petro Yasniy et al. / Structural Integrity Procedia 00 (2021) 000 – 000

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K I at the extreme (deepest) points of the saddle-shaped front of a series of studied contours to the values of SIF at the surface points C of the merging cracks were determined by: = = 1 , (1) The results of research to determine the coalescence factor γ coal (output factor) depending on the change of input factors a/ 4 c , where a is the depth of each of two identical coplanar surface cracks that merge; 4 c is the length of the major crack on the surface of the sample, as well as the ratio a coal / a , where a coal is the distance from the surface of the sample to the deepest point of the saddle-shaped front of each of the simulated contours, are presented in table 1. The γ coal data obtained by the FEM during the simulation of the coalescence of two identical surface cracks for four levels a /4 c = 0.075; 0.125; 0.175; 0.250 at different values of a coal / a (from 6 to 8 values at each level) is shown in Table 1.

Table 1. Input and output factors of the simulation experiment of coalescence of two identical coplanar surface cracks

⁄ 0.10

⁄4

Input factors

№

Output factor γ coal

1 2 3 4 5 6 7 8 9

3.20 2.10 1.80 1.70 1.70 1.85 4.10 2.40 2.00 1.80 1.60 1.55 3.40 2.45 1.96 1.73 1.58 1.51 1.48 1.48 4.48 3.12 2.38 2.03 1.87 1.69 1.61 1.57

0.20 0.30 0.40 0.60 0.80 0.10 0.20 0.30 0.40 0.60 0.80

0.075

0.125

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

0.149 0.256 0.378 0.491 0.626 0.754 0.850 0.950 0.154 0.270 0.407 0.530 0.618

0.175

0.175

0.25

0.76 0.85 0.95