Issue 41

S. Beretta et alii, Frattura ed Integrità Strutturale, 41 (2017) 269-276; DOI: 10.3221/IGF-ESIS.41.36 272 Figure 3 : Precision of SIF calculation depending on the crack length and the dimension of the regression region for the CCT specimen. The regression based only on the K term is always overestimating the SIF and only for very small regression regions it gives accurate SIF solutions; the solution including the K term and the T-stress tends to underestimate the SIF, even though the solution is accurate for relative for dimensions of the regression area up to 0.2 mm . The 3-terms regression results in the most stable and accurate SIF estimations. In particular, it requires regression dimensions higher than d>0.2mm which can be adopted in DIC measurements.