PSI - Issue 80

M. Bennebach et al. / Procedia Structural Integrity 80 (2026) 136–145 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 9. Hot spot stress extrapolation from strain gauges

Fig. 10. Hot spot stress extrapolation from FE model

Once calculated the hot spot equivalent stress, the life evaluation is made from the Stress-Life or Wöhler curve corresponding to a fatigue class of 71MPa (see figure 11) and a Miner damage accumulation rule. For a hot spot stress range in the critical location of 109 MPa, the calculated life based on a welded fatigue class of 71 MPa is: =2.10 ! ∗( 1 7 0 1 9 + " = 552746 . Damage is then calculated and linearly incremented on a daily basis, n cycles of stress per day inducing a value of damage n/N. This value is then reported on a dashboard and information regularly transmitted to an operator.