Wind Energy

296 P. Schaumann and F. Wilke
54.4 Conclusion
Fatigue design is a multiparameter challenge. The number of parameters
significantly increases the sensitivity of results when applying local concepts,
in particular the notch strain approach. Therefore experimental verification
of the theoretical analysis is indispensable but unlikely for the extreme large
dimensions of the proposed structures. Nevertheless the two local concepts
show their benefits if transfer to new structures or weld types is needed. For
offshore structures with actions in the high-cycle region, the notch stress approach
should be chosen. The application of the notch stress approach has
shown a very good compliance with the structural stress approach for the
weld toe locations, but great differences in fatigue strength for the roots. Here
the design rules for single-side welded joints have to be examined in more
detail with fracture mechanics.
References
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