According to Table 1, the presence of microcrack in vicinity of the semi-infinite crack, can amplify, reduce and also arrest the propagation of semi-infinite crack. whatever the positioning of microcrack with respect to the semi-infinite crack (\(\forall\alpha\ \epsilon\left[0\ ,\ 2\pi\right]\ \text{and\ }\ \forall\theta\ \epsilon\left[0\ ,\ 2\pi\right])\), the tables 3-4 summarize the amplification, reduction zones and arresting the propagation of the semi-infinite crack.

Table 3  Amplification and reduction zones of the propagation of semi-infinite crack.

In case ; α \(\epsilon\)[0, π/2[\(\cup\ \)]π/2, π]\(\cup\)[π, 3π/2[\(\cup]3\pi/2,\ 2\pi]\) and\(\forall\theta\ \epsilon\left[0\ ,\ 2\pi\right]\)