PSI - Issue 24

Giulia Morettini et al. / Procedia Structural Integrity 24 (2019) 349–359 Author nam / Structural Integrity Pro edi 00 (2019) 000 – 00

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(b)

Fig. 2. S-N Curve of Vertical specimens, (a) confidence bands using ASTM E739-10, (b) confidence and probability bends using ISO 12107

In Figure 2(a) and Figure 3(a), the linear regression curve of the experimental data, is reported with 95% confidence bands generated following the indications of the ASTM E739-10 standard. In both cases, the dispersion is low, symptom of a good conduction of the tests and of a high reliability of material behavior, in fact, practically all the test cases are contained within these bands. The consistency of the experimental results, in statistical terms, is also confirmed by the low value of the standard deviation of number of cycles σ̌ Nc , shown in Table 2. (a)