following relationship with the breaking wave height was obtained: 



h = 0.66 H^, 



(10) 



Equation 10 is plotted in Figure 18. The coefficient of determination of the 

 regression line was 70 percent. 



248. For the cases where a small bar formed on an accretionary profile, 

 the crest depth had a tendency to decrease slightly with time if onshore bar 

 movement occurred, which contributed to the scatter in the data. Sunamura (in 

 press) found a coefficient of 0.59 as opposed to 0.66 in Equation 10, based on 

 small-scale laboratory wave tank data and some CRIEPI data. 



2- 



o: CE 



■: CRIEPI 



Hb (m) 



Figure 18. Depth-to-bar crest h^, 

 wave height H^, 



versus breaking 



Ratio of trough depth to crest depth 



249 . The maximum depth occurring immediately shoreward of the bar was 

 taken as the trough bottom in the analysis. This was considered as a natural 

 and objective definition of trough position, although a trough was sometimes 

 located in an area where material accreted with respect to the initial 



88 



