534. Bruun fill . In the second fill alternative, material was deposi- 

 ted mostly along the subaqueous portion of the profile in accordance with the 

 equilibrium shape of the beach (called a Bruun beach fill ). Bruun (1988) has 

 advocated "profile nourishment," as opposed to placing fill material only on 

 the upper part of the profile, under the concept that the beach can best 

 resist erosive wave action in its most natural shape. The fill volume was 



85 m^/m, the same as for the artificial berm. Figure 89(a and b) shows the 

 simulation result for the two grain sizes studied. The amount of subaerial 

 erosion was reduced significantly even though the entire profile was submerged 

 during much of the storm surge. Bar development was less pronounced for the 

 0.25-mm beach compared to the artificial berm case, whereas the 0.40-mm beach 

 showed stronger bar formation. 



535. Summary . The numerical model provided qualitatively reasonable 

 results in calculation of the response of hypothetical beach cross sections to 

 storm events. In the examples, the Bruun fill provided better overall protec- 

 tion of the subaerial beach according to the numerical model , and less 

 material was redistributed along the profile during the storm surge compared 

 to the artificial berm design. Examples given in this section are described 

 further by Kraus and Larson (1988b). Larson and Kraus (in press) extend the 

 analysis further to consider model predictions for erosion of various cross 

 sections to a synthetic hurricane and a synthetic extratropical storm with 

 return periods of approximately 2-5 years. 



229 



