82. Prototype values in Table 1 were reported by Uliczka and Dette (1988). Model mean sediment fall 

 speed was calculated using the formulation given by Hallermeier (1981) with 0.13 mm as the diameter of 

 the quartz sediment and assuming a water temperature of 77 °F. 



83. The scale ratio for the sediment fall speed was determined as 



4.47 

 1.64 

 This was then used to determine both the time scale ratio and the length scale ratio as given by 

 Equation 6, i.e., 



Nt = N^= 2.73 

 and 



Ni = N^^ = 7.45 

 For convenience Ni = 7.5 was chosen as the length scale. Table 2 presents prototype and scaled model 

 parameters used for the tests. Several of these parameters are illustrated on Figure 6. 



Table 2. Prototype and Model Experiment Parameters 



Parameter 



Prototype 



Model 



Wave Period 



6.0 s 



2.2 s 



Wave Height 



1.5 m 



0.2 m 



Water Depth 



5.0 m 



0.67 m 



Horizontal Berm Width 



11.0 m 



1.47 m 



Berm Thickness 



2.67 m 



0.36 m 



84. Note that strict geometric scaling using the specified prototype and model grain sizes would have 

 resulted in a length scale ratio of A^^ = 0.33 mm/0.13 mm = 2.54. This illustrates the utility of the fall 

 speed parameter scaling guidance in that larger length scale ratios are permitted, thus allowing modeling 

 to be conducted in smaller facilities. An interesting experiment would be to attempt reproduction of the 

 selected prototype event in a large-scale wave flume using geometric scaling of the sediment between 

 prototype and model. 



Testing Procedure 



85. The procedures used for all tests were intended to duplicate the procedures used by Dette and 

 Uliczka (1986, 1987) for the GWK tests. The initial sand slope was smoothed to a l-on-4 slope (as 



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