The empirical formulas of Van der Meer (1988) indicate that breakwater 

 damage due to depth-limited waves is a function of A',, T„, and time t. In addition, it is 

 likely that damage is a function of structure slope, structure permeability, armor 

 gradation, armor porosity, armor stone shape, and method of armor placement. None of 

 these latter parameters except armor gradation were varied in this study. Gradation is 

 discussed in Chapter 7. The remainder of the parameters will be investigated in future 

 studies. 



In the following, the depth-limited breaking-wave stability data of Van der 

 Meer (1988) will be used to develop relations for damage progression. His depth- 

 limited wave and measured damage data are shown in Table 6.1. The particular data set 

 shown in Table 6.1 corresponded to a structure slope of 1V:2H, a beach slope of 

 1 V:30H, and the stone armor characterized by Dgj / D,5 = 1.25, D„^q= 3.60 cm, and 

 A=1.615. The table shows that, for toe depth h, = 0.4 m, the waves were only 

 marginally depth limited because HJh, was in the range 0.26-0.3 1 . Therefore, Van der 

 Meer's data provide only eight tests where the waves were clearly depth limited {h, = 

 0.2 m). The temporal development of damage cannot be deduced from these data 

 because the damage was only given after 1,000 waves and 3,000 waves. 



From Van der Meer's data, it can be seen that the surf similarity parameter 

 with respect to the beach slope for the eight breaking wave tests 9-16 ranged from 0.20 

 to 0.25. This suggests that all were spilling breakers, which is not the worst case for 

 armor stability. As explained in the previous chapters, plunging breakers expose the 



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