breaking wave height, not producing as good agreement as linear wave theory in 

 comparisons with the LWT data. 



548. In the numerical model, the net cross -shore sediment transport 

 rate distribution is determined by using local wave properties along the 

 profile. The profile is divided into four zones according to findings from 

 the LWT data sets, and the respective transport relationships are used to 

 determine the transport magnitude. Transport direction is determined from an 

 empirical criterion derived from the LWT data sets, which predicts bar or berm 

 profile development. Changes in the profile are determined from the mass 

 conservation equation. The model proved to be numerically stable over a wide 

 range of conditions, and simulated profiles approached an equilibrium configu- 

 ration if exposed to constant waves and water level. 



549. The model was calibrated against seven cases from the CE and 

 CRIEPI experiments showing foreshore erosion and bar formation. The optimal 

 value of the empirical rate coefficient for the transport relationship applied 

 in zones of broken waves was 1.6 10~^ m^/N. The model was then verified 

 against two independent cases from the CE and CRIEPI experiments with the 

 parameter values given by the calibration. Good agreement was obtained 

 between calculated and measured profiles regarding both the amount of fore- 

 shore erosion and the movement and size of the main breakpoint bar. The bar 

 trough was less well reproduced, and smaller features inshore of the main 

 breakpoint bar were omitted in the simulations. The model was also tested 

 with one CE case which included a water level variation simulating a tide, and 

 this case was also satisfactorily reproduced. 



550. A number of hypothetical cases were simulated with the numerical 

 model to evaluate the influence of variations in incident wave height, wave 

 period, and water level. Sensitivity analyses were performed for a large 

 number of model parameters to establish their influence on bar formation. 

 Simulation for a hypothetical example which included a seawall on the fore- 

 shore showed that the size of the bar was approximately the same as for 

 simulations without the seawall, but the area immediately seaward of the 

 seawall experienced more erosion. Simulations of beach fill adjustment for 

 use in storm protection design were also performed as an example of the 

 utility of the model. 



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