4. Calculating fracture mechanics

4.1 Linear elastic fracture mechanics

In aeronautics, linear fracture mechanics is considered sufficient to assess the propagation time of a crack: in most cases, plasticity remains localized at the crack tip [18] .

Three zones can be distinguished in the vicinity of a crack (Figure 20 ):

• area around the crack tip;

• zone in which the stress field is characteristic of the crack and singular at $\sqrt{r}$ (elastic...