PSI - Issue 5

U. Zerbst et al. / Procedia Structural Integrity 5 (2017) 745–752 U. Zerbst et al./ Structural Integrity Procedia 00 (2017) 000 – 000

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the requirements of both, S-N curve and fracture mechanics considerations and multiple crack propagation. The principle of the stochastic analyses was demonstrated for fatigue cracks originating at weld toes.

Fig. 10: (a) Effect of the stress ratio R (=  min /  max ) on the modify- cation of the residual stress state (at weld toe); according to Tchoffo Ngoula et al. (2017) (b) The conservative predict- tion of the finite life fatigue strength might be a conse- quence of the compression re- sidual stresses introduced by the cycling at R = 0. Whilst the analysis was performed for this nominal R, the real R was smaller due to the mean stress effect of the compressive resi- dual stresses.

References

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© 2017 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the Scientific Committee of ICSI 2017.