Issue 54

M. Belaïd et alii, Frattura ed Integrità Strutturale, 54 (2020) 202-210; DOI: 10.3221/IGF-ESIS.54.15

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oR OR Q P 

The Figs. 4 and 5 respectively present the variation of (J/Je) according to the pressure ratio (P/P oR ) for a different ratio (a/t) for n=5 and n=10. Compared with the analytical solution of Eqn. (10) found in the literature, it can be noticed that the effect of the ratio a/t becomes sensible when the ratio (P/P oR ) exceeds 1.0. This shows a very good correlation between the two methods when the ratio a/t = 0.2 and a/t = 0.5, for a/t = 0.7 the difference is significant especially at high (P/P oR ) but for n=10 the difference is significant (see Fig. 5).

Figure 4: Comparison of the FE J results with those estimated from the proposed ERSM for the internal pressure for n=5

Figure 5: Comparison of the FE J results with those estimated from the proposed ERSM for the internal pressure for n=10.

P ROBABILISTIC E LASTIC - PLASTIC F RACTURE M ECHANIC A NALYSIS

Random parameters and fracture response he J -integral is an appropriate fracture parameter that describes the crack-tip stress and strain fields adequately when there are no constraint effects [24]. Probabilistic models have also been developed to estimate various response statistics and reliability [25]. Using FEM, one can calculate J for any crack geometry and load conditions. However, it is also useful to have simplified estimation methods for routine engineering calculations. Accordingly, the probabilistic EPFM analyses based on both methods have been reported [26,27] T

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