PSI - Issue 68

Q.M. Vuong et al. / Procedia Structural Integrity 68 (2025) 887–893 Q.M. Vuong et al. / Structural Integrity Procedia 00 (2024) 000–000

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(a) Mesh of the problem (b) Experimental config uration Vicentini et al. (2024)

(c) Flowchart for the resolution

Fig. 1: Presentation of the studied configuration, and the implementation strategy.

(a) Miehe’s strain decomposi tion Miehe et al. (2010)

(b) Amor’s strain decomposi tion Amor et al. (2009)

(c) Wu’s stress decomposition Wu (2017)

Fig. 2: Comparison using stress - strain decomposition

3.2. Comparison of Phase Field Model: AT1 and PF-CZM

AT1 and PF-CZM model have been used to study the crack’s initiation in the considered configuration. AT1 model is considered as able to capture the initiation phenomenon. The Young modulus have been set as E = 6 GPa, while the Poisson ratio is 0.12. Due to its intrinsic dependence on l c and the unavailability of G c in the literature, the value of l c have been set to 0.4 mm, corresponding to a fracture energy release rate equal to 0.18 N / m 2 . Results are proposed in figure 3. Results confirms that, at the onset of cracking (point 1 in figure 3), initiation is governed by the maximal prin cipal stress, a feature well captured by AT1 model with the Miehe decomposition scheme. The observed little over estimation of the failure stress is consistent with literature Kristensen et al. (2021). The decrease of the maximal principal stresses after crack initiation can be explained by the coupled criterion Leguillon (2002); Molna´r et al. (2020).

3.3. Crack propagation under pressure

To complete this parametric study, following Vicentini et al. (2024), an uni-axial pressure equal to 3 MPa is applied on the top of specimen. The Miehe’s strain decomposition and Wu’s decomposition are considered and compared, as the Amor’s one has been proven not realistic in this context. Results can be seen in figure 4.