Issue 37

R. Sepe et alii, Frattura ed Integrità Strutturale, 37 (2016) 369-381; DOI: 10.3221/IGF-ESIS.37.48 380 Figure 10 : Mean of the crack init. time [ms] vs. MC trial. Figure 11 : Std dev. of the crack init. time [ms] vs. MC trial. In this case, the variability of the critical remote value can reach the 8% of its mean value, which is a rather appreciable difference to be taken into account when we try to fit the experimental results with numerical ones. C ONCLUSIONS he use of the SDI approach to calibrate the physical and correction parameters of the GT model is an useful numerical tool that provides a numerical model able to well represent the real development of the considered phenomena even if the involved physical parameters are subjected to natural variability. Within this work we investigated on the feasibility to apply the SDI approach, and we used it to calibrate the physical nucleation parameters of the GT model. The results were satisfactory and the R-curve of the examined component, obtained by using the nominal value of the found nucleation parameters, is in good agreement with the experimental one. In the last paragraph, some sensitivity analyses showed that the natural scatter of the material properties and of the nucleation parameters around their “nominal” value do not influence considerably the toughness of the material in the considered reference case. R EFERENCES [1] Newman Jr., J.C. The merging of fatigue and fracture mechanics concepts: a historical perspective, Progress in Aerospace Sciences. 34 (1998) 347-390. T