PSI - Issue 28

A.M. Al-Mukhtar / Procedia Structural Integrity 28 (2020) 124–131

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A.M. Al-Mukhtar/ Structural Integrity Procedia 00 (2020) 000–000

Fig. 3. Meshes and boundary conditions, CASCA [36]

3. Results 3.1. Crack Path Simulation

The crack initiation from the rounded hole is presented. The maximum hoop stress theory was exploited in Franc2D to predict the direction of the crack growth when it was perpendicular to the nominal applied load. However, biaxial loading were used. In this program, the crack is propagated automatically or gradually according to the maximum stress direction. Moreover, in this study, the crack path was not pre-selected, but crack direction was allowed to change according to the maximum tangential stress criterion [42], [43]. In general, the behavior of crack path in Franc2D (Fig. 4) is almost the same as compared with the case study of Southwest's flight 812 in Fig. 2, see Ref. [35]. Figure 4d shows the stress map and maximum stresses point along the crack path.

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