Recently, the authors developed a numerical model to simulate evolution of 

 the beach profile in response to breaking waves (Larson 1988, Larson, Kraus , 

 and Sunamura 1988). Required inputs are initial profile and fill configura- 

 tion; median grain size; and time series of significant wave height, peak 

 spectral wave period, and water level for the calculation interval. The model 

 is compatible with Equation 1 and reproduces formation and movement of the 

 main breakpoint bar and, to a lesser extent, the berm. 



In this paper, test applications are presented to illustrate model predic- 

 tions of profile adjustment to a storm event. Three representative beach 

 profiles, an existing condition and two fills of different cross-sectional 

 form, are subjected to a simplified and synthetic 30-day time series of waves 

 and water level that includes a severe storm. Evolution of the existing and 

 nourished beaches is calculated, and relative performances of the three 

 profile configurations are compared, including dependence of fill adjustment 

 on grain size. 



NUMERICAL MODEL 

 Background 



Initial model development relied on data from two independent laboratory 

 experiment programs replicating cross -shore processes in very large wave 

 tanks. One program was conducted by the U.S. Army Corps of Engineers (CE) in 

 the years 1956-1957 and 1962 (Saville 1957, Kraus and Larson 1988), and the 

 other in the early 1980s by the Central Research Institute of Electric Power 

 Industry (CRIEPI) in Japan (Kajima et al . 1982). The combined CE and CRIEPI 

 data set covers wave heights in the shoaling zone ranging from 0.31 to 1.80 m, 

 wave periods from 3.1 to 16.0 sec, initial beach slopes from 1/10 to 1/50, and 

 four median grain sizes ranging from 0.22 to 0.47 mm. In the analysis, 33 

 major cases in the combined data set were used, each case consisting of 

 numerous profile surveys made under a unique combination of incident wave 

 conditions, initial beach slope, and grain size. Kraus and Larson (1988) give 

 a description and listing of the CE data, and Larson (1988) summarizes both 

 the CE and CRIEPI data sets. 



Because the tank studies mainly involved monochromatic waves and constant 

 water levels, the model was further tested and refined by use of field data 

 sets on profile change obtained by the Coastal Engineering Research Center's 



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