1. Some results on cut-off frequency
FATIGUE COUNTS
Some results on cut-off frequency
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2. RAINFLOW COUNTS
A. How conservative is the narrow-band approximation for a unimodal spectrum ?
It may be noted that M0 and M2 are normalizing factors, and thus normalized damage for a Pierson-Moskowitz depends only on m, for a Jonswap on m and , etc.
Sensitivity to spectral bandwidth.
Sensitivity to spectral shape.
Sensitivity to cut-off frequency.
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3. West Africa Spectra -> Wide band wave action
Mooring responses -> Composite signals
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4. Is this a wideband spectrum ?
If yes, is it because of the ears or of the tail ?
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5. Which is the widest ?
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6.  = 0.776
 = 0.604
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7. Effect on the rainflow ranges distribution when removing the spectrum tail: very similar to removing the smallest cycles.
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8. For each cut-off frequency and value of m, we can define an equivalent endurance threshold.
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9. A collection of spectra with various bandwidths
Jonswap gamma=1,3,7
Wallops f-4, f-3, f-2
A collection of spectra with various bandwidths
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10. Effect on damage
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11. Effect on damage
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12. Effect on damage
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13. Effect on damage
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14. Effect on damage
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15. Effect on damage
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16. Loss of spectral contents
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17. Loss of spectral contents
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18. Equivalent thresholds
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19. Equivalent thresholds
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20. Equivalent thresholds
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21. Equivalent thresholds
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22. Equivalent thresholds
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23. Equivalent thresholds
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