Issue 42

M. Peron et alii, Frattura ed Integrità Strutturale, 42 (2017) 205-213; DOI: 10.3221/IGF-ESIS.42.22 207 It can be noted, comparing the uncoated and coated series (Fig. 2), that the scatter index reduces from 1.6 to 1.3. This value is reasonably low both for the uncoated series and the galvanized one. Moreover also in terms of fatigue strength the effect of the galvanization is found to be negligible with a reduction, at N = 2×10 6 and Ps = 90%, from 83 to 82 MPa. Furthermore, from the data summarised in Fig. 3, it is possible to see that the fatigue strength at N = 2×10 6 and Ps = 90% is 75 MPa: this value is comparable with the fatigue stress range (from 71 to 80 MPa) given for the corresponding detail category in Eurocode 3. Figure 2 : Fatigue behaviour of bare (left) and galvanized (HDG, right) welded steel at R = 0. Figure 3 : Fatigue behaviour of both uncoated and galvanized welded steel at R = 0. S TRAIN ENERGY DENSITY APPROACH n averaged strain energy density (SED) criterion has been proposed and formalized first by Lazzarin and Zambardi ([16]), and later has been extensively studied and applied for static failures and fatigue life assessment of notched and welded components subjected to different loading conditions [17]. According to this volume- based criterion, the failure occurs when the mean value of the strain energy density over a control volume with a well- W A