531. Initial wave conditions produced erosion for the 0.25-ram grain 

 size (Figure 87a) , and a small bar developed offshore with the shoreline 

 receding somewhat. As water level increased during the storm, the beach in 

 front of the seawall was submerged, and considerable erosion occurred. The 

 high seawall prevented the beach from retreating. A long flat bar developed 

 during the peak of the storm which moved offshore with the break point as the 

 water level decreased. After the storm, the inshore portion of the profile 

 partly recovered, producing buildup on the foreshore and a bar-like feature 

 just below the still -water level. The main part of the bar, however, did not 

 contribute material for the recovery process since it was located too deep and 

 too far seaward of the breaking waves. 



532. The equilibrium profile of the 0.40 -mm sand was much steeper than 

 the 0.25-mm beach (Figure 87b) because of the grain-size dependence of the A- 

 parameter in Equation 1. Mild waves arriving during the initial part of the 

 simulation period produced onshore transport and a small berm. During the 

 storm surge, the amount of subaerial erosion was similar to that in the 0.25- 

 mm profile example, but the bar did not migrate as far offshore. The recovery 

 of the 0.40 -mm beach did not produce such a marked trough seaward of the bar- 

 like feature as did the 0.25-mm beach. 



533. Artificial berm . The first type of beach fill evaluated was an 

 artificial berm consisting of approximately 85 m''/m of material placed on the 

 subaerial portion of the beach. In simulations with the beach fill, it was 

 assumed that the fill material was identical to the natural beach sand. A 

 small bar formed before the storm, much in agreement with the case without the 

 fill but closer to shore. During the storm, a large part of the fill eroded 

 and was deposited offshore. Figure 88(a and b) illustrates simulation results 

 for the 0.25- and 0.40-mm grain sizes. Although significant recovery occurred 

 for the 0.25-mm beach, a large amount of material was trapped offshore. The 

 eroded material from the artificial berm for the 0.40-mm beach was deposited 

 closer to shore, and during the recovery phase the entire bar moved slightly 

 onshore . 



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