PSI - Issue 45

Teresa Magoga et al. / Procedia Structural Integrity 45 (2023) 28–35 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

33

6

Fig. 2. (a) Profile view schematic of patrol boat, showing strain gauge locations, b) stress spectra at strain gauge locations

3. Analysis and Results Different Eurocode 9 details are considered in the fatigue life analysis of the details of interest (listed in Table 1), based on consistency of category, weld type, and geometry. For example, Eurocode 9 detail 7.4.3 is potentially applicable to detail ID-1 because the category (butt weld) and geometry (hollow section) are consistent. However, the weld type is not consistent; ID-1 features a partial penetration weld whereas Eurocode 9 detail 7.4.3 is a full penetration weld. Alternatively, Eurocode 9 detail 7.5 may be appropriate because it is a partial penetration weld though the geometry differs to that of detail ID-1. Fig. 3 displays FL p normalised by FL m (given in Table 1) for details of interest ID-1, ID-2, ID-4, and ID-5 based on different Eurocode 9 details. As FL m is not applicable at ID-3, FL p normalised by the design life FL d is presented (Fig. 4). For each detail of interest the stresses are recovered (and in turn fatigue life calculated) at increasing distance between the element centroid and the weld intersection (d/t).

Fig. 3. d/t versus FLp/FLm at detail of interests ID-1, ID-2, ID-4, and ID-5

Fig. 4. d/t versus FL p /FL d at detail of interest ID-3