Crack Paths 2012

Figure 7. Varieties of simulated crack propagation life of an embedded elliptical crack.

(initial crack 2a=25mm,2b =5mm)

Table 2 Mean, standard deviation and C O Vof crack propagation lives

(initial crack 2a=25mm,2b =5mm)

Crack length

Initial crack 2b=5mm

5 m m 1 0 m m 1 5 m m 2 0 m m 3 0 m m 3 5 m m 4 0 m m

mean 1.98E+06 3.85E+06 5.03E+06 5.88E+06 6.86E+06 7.13E+06 7.33E+06

'Keff

std. dev. 1.29E+05 2.14E+05 2.49E+05 2.55E+05 3.46E+05 3.59E+05 3.78E+05

20 samples

C O V 6.50E-02 5.55E-02 4.96E-02 4.35E-02 5.05E-02 5.03E-02 5.15E-02

mean 5.68E+06 1.23E+07 1.62E+07 1.87E+07 2.14E+07 2.21E+07 2.25E+07

Krp

std. dev. 5.29E+05 1.17E+06 1.39E+06 1.51E+06 1.62E+06 1.63E+06 1.65E+06

20 samples

C O V 9.31E-02 9.46E-02 8.57E-02 8.09E-02 7.58E-02 7.37E-02 7.32E-02

F U R T H EDIRSCUSSIONS

SomeConsiderations about Retardation Effect

In order to investigate the effect of sequence of the clustered loads and the so-called

equivalent constant amplitude of loading, fatigue crack propagation is simulated for the

five cases explained below and the results are illustrated in Fig.8.

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