PSI - Issue 57

Inge Lotsberg et al. / Procedia Structural Integrity 57 (2024) 569–580 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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spot stress derivation when using shell elements. For research purpose and where detail classification is questioned it is possible to perform analysis using the effective notch stress method where weld toes and weld roots are modelled by a radius of 1.0 mm; see e.g. Sonsino et al. (2012) and Fricke (2013). Here the maximum calculated stress is read out from the analysis results and is combined with a notch S-N curve which is a factor 2.5 above the hot spot S-N curve; DNV-RP-C203 (2019). Thus, for comparison of results from the notch stress method with hot spot stress analysis the notch stress is divided by this factor. Calculated stresses along the plate surface at the hot spot from analyses 1-4 are listed in Table 2 and shown in Fig. 7. The calculated stresses through the plate thickness at the hot spot from these analyses are listed in Table 3. Analysis no 1: First the method A for derivation of hot spot stress from DNV-RP-C203 (2019) is used. The hot spot stress for Method A is derived from stresses in Table 2 as: ℎ = 1.5 +1.5( 0.5 − 1.5 ) = 1.141 + 1.5 ∙ (1.244 − 1.141) = 1.296 (3) The hot spot stress for Method B is derived as: ℎ =1.12 0.5 = 1.12 ∙ 1.244 = 1.393 (4) Table 2. Calculated stress along the plate surface at hot spot. Distance along surface from hot spot (mm) Analysis no 1 (MPa) Analysis no 2 (MPa) Analysis no 3 (MPa) Analysis no 4 (MPa) 0.0 1.488 1.883 1.927 1.378 5.0 1.429 10.0 1.244 1.301 1.178 1.280 15.0 1.194 20.0 1.173 1.114 1.168 1.189 25.0 1.154 30.0 1.141 1.150 1.135 1.155 35.0 1.122 40.0 1.110 1.101 1.110 1.114 45.0 1.101 50.0 1.094 1.092 1.091 55.0 1.084 60.0 1.077 1.075 1.077 3.3. Calculated hot spot stresses