Comparison with Prototype 



127. Representative profile comparisons between prototype and model after equal numbers of waves 

 (Froude scale for morphological development) are given in Figure 16. In these plots, the model results are 

 presented in prototype dimensions using the length scale ratio of 7.5. A complete set of profile comparisons 

 is given in Figure E7 in Appendix E (Irregular Test T14 versus Prototype). 



128. The comparison after 720 waves (Figure 16) shows that profile development in the model (solid 

 line) closely resembled that of the prototype (dashed line) with the exception of the amount of berm 

 recession. The calculated RMS variation between the profiles (as calculated by Equation 13) was 0.263 m. 

 After 2,770 waves, the model continued to match the prototype response to an uncanny degree (Figure 16) 

 with an RMS variation between profiles of 0.141 m. By the end of the test, the model profile showed some 

 variation from the equivalent prototype profile, but the reproduction was still considered to be very good. 

 The RMS variation between the profiles after 6,810 waves was 0.222 m. As seen in Figure 16, the model 

 did not erode quite as deeply in the foreshore area above the still- water line, a little more sediment was 

 carried offshore of the bar feature, and a slight bar-trough development occurred in the model that was not 

 present in the prototype profiles. 



129. The attempt to reproduce the irregular-wave prototype-scale flume experiment was considered to 

 be very successful. This further validates the selected movable-bed modeling guidance as being appropriate 

 for energetic regimes of sediment transport. It is significant that close reproduction was obtained over the 

 entire extent of the profile using properly scaled irregular waves. Recall from previously presented results 

 that the regular wave tests suggested augmentation of the model wave height to provide a better 

 correspondence of the Xie parameter between model and prototype. Because this was not required for the 

 case of irregular waves, it is tentatively concluded that the natural variations within the irregular wave field 

 were sufficient to assure correct redistribution of sediment over the entire extent of the modeled profile. 

 However, further validation of this conclusion would be desirable. 



Modeling Law Verification Conclusions 



130. Visual comparisons of prototype and model profile development due to regular waves indicate 

 that the movable-bed scaling criteria given by Equation 6 did a reasonable job of reproducing the 

 prototype-scale profile evolution in the physical model at reduced scale (test T03). However, the model did 

 not move as much sediment from the nearshore to the offshore region as was documented in the prototype 

 experiment. This appears to be caused by sediment coming to rest in the offshore portion of the model 

 under scaled conditions that would still promote bed-load transport in the prototype. 



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