ssc-367 - Ship Structure Committee

as a parametric study intended to identify the fatigue-susceptible
areas for improvement.
Considering that small increases in steel used can appreciably
increase fatigue lives, it is recommended that the target fatigue
lives (at least for a screening effort) be taken as five to ten
times the design life while most rules and reconunendationsspecify
a factor of two between fatigue and design life. Then, changes
introduced during design that has an impact on applied loads and
stress distributions can be readily accommodated.
9.5
RECOMMENDATIONS
Fatigue avoidance strategiesadopted and the design tools used have
served as well. However, further efforts are necessary in carrying
out more research, in developing further improvements in analyses
and design, and in upgrading the rules and regulations to
incorporate the research results.
Recommendationspresented in Section 5 through8 provided the basis
for further in-depth discussions in Section 9. Applicable
references in each section are listed in Section 10. Some of the
primary recommendations are listed as follows:
●
Although “allowable stress” methods may be used as a
“screening process,” a detailed fatigue analysis is often
necessary.
●
Assessment of various empirical equations indicate that the
UEGequations yield conservativepredictionofSCFs for awide
range of geometry. However, empirical equations provided by
UEG, Efthymiou,Kuang and others should be reviewed for joint
geometry and loading condition to allow selection of most
appropriate equation.
●
The long-term wave
models are quite
environment definitions based on hindcast
reliable. However, modeling parameters
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