submerged for much of the storm. A double bar system emerged again, but the 

 location of the inner mid -storm bar for the finer material was shoreward of 

 the pre -storm bar, caused by the rise in water level during the surge. Bar 

 development (with respect to the initial profile) for the finer grain size was 

 more pronounced than that for the artificial berm case, whereas the coarser 

 grain size showed less bar formation. The Brunn fill had less overall loss of 

 subaerial material than the artificial berm, and less material was redistri- 

 buted along the profile, confirming the concept that a beach is most stable if 

 in an equilibrium shape. However, because of its low placement elevation, the 

 Bruun fill allowed more exposure of the wall to wave action during the surge. 

 Berm development was absent in the recovery stage because the inner surf zone 

 and foreshore remained near the equilibrium state to dissipate incident wave 

 energy. 



DISCUSSION AND CONCLUSIONS 



A newly developed numerical model for simulating beach profile evolution 

 was applied to examine the adjustment of a hypothetical existing beach profile 

 and two fill cross -sections that might be used to nourish the beach. The 

 model is capable of describing the growth and movement of main breakpoint bars 

 and, to a lesser extent, corresponding berm processes. Breaking waves are 

 assumed to be the dominant mechanism causing sand transport and profile 

 change. The model utilizes standard engineering information as input, namely, 

 representative deepwater wave height (mean wave height to determine net 

 transport direction, and significant wave height to calculate cross-shore 

 transport), peak spectral wave period, water level, and grain size (from which 

 the fall speed is calculated) . Model results are not unduly sensitive to 

 initial profile configuration, which may not be precisely known in applica- 

 tions . 



The model is based on relationships for cross -shore sand transport 

 produced by breaking waves, implying that longshore sand transport can either 

 be neglected or is uniform. Thus, caution must be exercised in applying the 

 model and interpreting results if gradients of longshore transport exist. 

 Longshore transport is expected to be a major contributing process to beach 

 change over long time periods, for example, seasons to years. For such time 

 frames, the present model should be combined with other predictive methodol- 



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