damage initially. Waves 2 and 3 at the lower water followed but caused little additional 

 damage to the segment of the armor layer damaged by Waves 4-6. This suggests that 

 the damaged armor layer can withstand subsequent wave action at a lower intensity if 

 the wave action is confined to the damaged area. 



As one would expect, the damage rates differed for the different storm 

 ordering. But the ultimate damage at the end of the storm sequence was surprisingly 

 consistent. Both the mean damage and the standard deviation for the four repeats were 

 consistent. At the end of Series B' and C after approximately 18,000 waves, S= 8 and 

 O5 = 2 for both series. Although the testing was by no means comprehensive, it suggests 

 that damage and variability are similar after being exposed to similar cumulative wave 

 action with different sequences. This is useful in determining the reliability of a 

 structure because the cumulative damage may be assumed to be the sum of damages 

 caused by individual storms. 



5.5 Characteristics of Profile Erosion 



For Series A', the mean minimum cover depth was computed as the average 

 of the minima from the 16 profiles, while the mean eroded depth was computed as the 

 mean of the maxima from the 16 profiles. Figure 5.13 shows the mean eroded depth 

 versus number of waves, and Figure 5.14 shows the mean cover depth versus number of 

 waves, both for Series A'. These figures clearly show the periodic healing process as a 

 jagged sawtooth shape to the curves. They also show that the armor layer thickness 

 decayed to an equilibrium level, with an asymptote at C = 0. Figure 5.15 shows that the 



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