Issue 60

H. Benzineb et al., Frattura ed Integrità Strutturale, 60 (2022) 331-345; DOI: 10.3221/IGF-ESIS.60.23

Figure 11: Variation of the damaged zone ratio D R vs the temperature for the Graphite-epoxy type.

Figure 12: Variation of the damaged zone ratio D R vs the temperature  T for the Glass-epoxy type. Variation of stress intensity factor in mixed mode as a function of temperature Δ (T) for the different types of the patch The criterion of Von-Mises is used as criterion of plasticity. The theory of additional plasticity is introduced to model the non-linearity of the adhesive material. The stress intensity factors at the crack tip are calculated using the virtual crack closure technique (VCCT) based on the energy balance. In this technique, the stress intensity factors are obtained for the three failure modes according to the equation:

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