numerical model which has the capability to reproduce bar and berm formation 

 and movement (Larson 1988, Larson and Kraus 1989). For this purpose, one 

 synthetic hurricane and one synthetic extratropical storm are used to examine 

 the response of two beach fill configurations of different grain size to storm 

 and post-storm wave action. 



BACKGROUND 



The beach can be considered as a flexible structure that protects life and 

 resources along the coast. Recreational beaches are themselves resources 

 which may also have a protective function. Coastal engineering design and 

 planning require estimation of the functioning of the protective beach in 

 analogy to the design process for conventional engineering coastal structures 

 such as seawalls and breakwaters. 



A significant advance in the practical estimation of storm- induced dune 

 erosion was made by Kriebel (1982, 1986) and Kriebel and Dean (1985), who used 

 the equilibrium profile concept of Bruun (1954) and Dean (1977) to develop a 

 relationship for the net cross -shore sediment transport rate based on energy 

 dissipation of breaking waves in the surf zone. The resultant numerical model 

 allows time -dependent calculation of beach and dune erosion, in which depth 

 along the profile increases monotonically with distance offshore as governed 

 by the incident wave energy and grain size. Scheffner (1988, 1989) embedded 

 the "Kriebel" model in a stochastic calculation procedure to develop dune 

 erosion- frequency of occurrence curves for evaluation of alternative dune 

 designs. Birkemeier et al . (1987) compared available procedures and concluded 

 the Kriebel model offered the most reliable and practical means to calculate 

 storm- induced erosion on U.S. beaches. 



Based on the success of the Kriebel model, the authors conducted a study 

 to improve and verify the capabilities of a wave dissipation-based numerical 

 approach for calculating storm-induced beach erosion (Larson 1988; Larson, 

 Kraus, and Sunamura 1988, Kraus and Larson 1988, Larson and Kraus 1989). The 

 model was established by using an extensive data set from laboratory experi- 

 ments with prototype -scale waves and beaches (Larson 1988, Kraus and Larson 

 1988) and verified with field data. The model, called SBEACH, for Storm- 

 induced BEA ch CHange , was developed with the objectives of: (1) accurate 

 calculation of beach and dune erosion, (2) representation of bar formation and 



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