3. The empirically-based numerical model used in this study and 

 similar modelsprovide good qualitative results for a wide range of 

 processes associated with storm- induced beach erosion. Quantitative 

 results are reasonable, but testing of this class of models must 

 continue, with emphasis on field verification and model refinement. 

 The present model describes bar formation, growth, and migration with 

 reasonable reliability. Although not discussed here, improvements in 

 the model are required to better represent berm growth and recovery 

 processes (Larson 1988, Larson and Kraus 1989). 



4. The model can be used to judge the relative behavior and merits of 

 various beach fill cross-sections exposed to typical and extreme waves 

 for time intervals on the order of days to a month (see also, Kraus 

 and Larson 1988). 



5 . Fill placed on the upper beach was calculated to move offshore to 

 relatively deep depths, in agreement with the generally inferred 

 behavior of the movement of beach fill material . 



6. The limited number of calculations performed here indicates that it 

 may not be cost-effective to use beach fill with a median grain size 

 much greater than 0.4 mm owing to the typically greatly increased cost 

 of such material and the declining benefit in decreased volume of 

 eroded material. Design alternatives for specific situations 

 (available fill material and cross-sections) could be evaluated with 

 the model . 



ACKNOWLEDGEMENTS 



The authors wish to thank Coastal Engineering Research Center colleagues 

 Mr. H. Lee Butler and David B. Driver, and Drs. C. Linwood Vincent and Norman 

 W. Scheffner, for helpful discussions on the storm parameterization, Dr. Mark 

 R. Byrnes and Ms. Kathryn J. Gingerich for critical reading of an early draft 

 of the manuscript, and Mr. Barry Sommerfeld for assistance in data manipula- 

 tion and preparation of the figures. 



The contribution of N. C. Kraus was made as part of the activities of the 

 Cross-Shore Sediment Transport Processes work unit of the Shore Protection and 

 Evaluation Program, Coastal Engineering area of Civil Works and Development, 

 being executed by the Coastal Engineering Research Center, U.S. Army Engineer 

 Waterways Experiment Station. He appreciates permission granted by the Chief 

 of Engineers to publish this information. 



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