Figure 4.3. Photograph of model structures before testing 



In armor stabihty experiments, breakwater crest heights are usually set high 

 enough to prevent overtopping from influencing the stability, unless overtopping is the 

 focus of the study or the breakwater is low crested. But the composite downslope 

 weight of upslope armor units generally contributes to the stabiUty of the armor layer 

 and increases as the slope lengthens; although under some conditions, longer armor 

 layers can have a tendency to buckle or slide. Just considering stone stability, for a 

 given wave height, taller structures are typically more stable, with respect to main armor 

 stability, than short structures. But, in the prototype, the cost of the breakwater is kept 

 to a minimum by setting the breakwater crest height such that minor overtopping is 

 allowed for a design wave condition. Thus, experimenting with non-overtopped 

 structures that have high crest heights typically will not be conservative with respect to 



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