PSI - Issue 81

Ivan Pidgurskyi et al. / Procedia Structural Integrity 81 (2026) 47–53

51

Fig. 5. Block diagram of simulation modeling of the mutual interaction of two identical coplanar surface cracks.

It has been established that when the distance between cracks t s is comparable to or smaller than the dimensions of the interacting cracks, an increase in the interaction factors is observed (Table 1). In particular, as the cracks approach each other, the values of γ С at the points of the inner semi-contours of the cracks increase significantly. At the same time, the increase in γ A values at the deepest points of the cracks is less pronounced (Table 1). An increase in the surface crack aspect ratio ( a / c = 0.2, 0.5, and 0.8) as well as in the relative crack depth ( a / t ) results in similar trends in the variation of the interaction factors γ С and γ A are observed. The results of the simulation experiment (Table 1) were obtained based on the implementation of a designed three-factor experiment with three levels of factor variation. The mutual interaction between surface cracks approaching each other is characterized by the interaction factors γ С and γ A , which serve as output parameters. These factors are defined as the ratio of the stress intensity factor (SIF) at characteristic points of interacting cracks to the SIF at the corresponding points of a single identical surface crack.

Table 1. Input and output parameters for modeling the interaction of two identical surface cracks

№

a / t

a / c

t s / c 0.8 0.8 0.8

γ C

γ A

№

a / t

a / c

t s / c 0.4

γ C

γ A

1 2 3 4 5 6 7 8 9

0.025 0.2 0.0625 0.5

1.004 1.001 1.0151 1.0053 1.0277 1.008 1.0294 1.012 1.0759 1.033 1.1206 1.062 1.0155 1.008 1.028 1.011 1.0478 1.015 1.0502 1.018 1.1406 1.044 1.2068 1.072 1.0209 1.01 1.059 1.028

15 16 17 18 19 20 21 22 23 24 25 26 27

0.5

0.8

1.0842 1.041 1.004 1.002 1.0276 1.013 1.0438 1.022

0.125 0.2 0.3125 0.5

0.64 0.64 0.64

0.1

0.8

0.075 0.2 0.1875 0.5

0.27 0.27 0.27 0.67 0.67 0.67 0.16 0.16 0.16

0.5

0.8

0.1667 0.25 0.3333 0.5 0.5333 0.8 0.1667 0.25 0.3333 0.5 0.5333 0.8 0.1667 0.25 0.3333 0.5 0.5333 0.8

0.1 0.1 0.1

1.12 1.31 1.46 1.07 1.18 1.31 1.06 1.14 1.24

1.03 1.07 1.11

0.3

0.8

0.075 0.2 0.1875 0.5

0.25 0.25 0.25

1.028 1.065

0.3

0.8

10 11 12 13 14

0.125 0.2 0.3125 0.5

1.09

0.4 0.4 0.4

1.023 1.059 1.086

0.5

0.8

0.125 0.2 0.3125 0.5

0.4 0.4