other a formula derived by Dean (1973) based on the assumption that the major 

 sand transport occurs as suspended load. Most analytical solutions then 

 appearing in the literature were presented by Walton and Chiu (1979). Addi- 

 tional solutions mainly concern beach nourishment in connection with various 

 shoreline shapes. The new solutions derived by Walton and Chiu (1979) treat 

 beach fill in a triangular shape, a rectangular gap in a beach, and a semi- 

 infinite rectangular fill. Some data on the coastal constant are also pre- 

 sented in the paper. 



27. Analytical solutions can be used conveniently to describe the be- 

 havior of beach fill, as mentioned above. Dean (1984) gives a brief survey of 

 some solutions applicable to beach nourishment calculations, especially in the 

 form of characteristic quantities describing loss percentages. One solution 

 describes the shoreline change between two groins initially filled with sand. 

 The resultant shoreline evolution with time is shown in Figure 6. 



Figure 6. Shoreline evolution between two groins initially filled 

 with sand (after Dean 1984) 



General Approach in the Present Work 



28. The simplified or linearized shoreline change equation (Equation 9) 

 is a linear partial differential equation which is identical to the equation 

 describing one-dimensional conduction of heat in a solid or to the diffusion 

 equation. By specifying boundary and initial conditions in these areas which 

 represent conditions prevailing in a specific shoreline evolution situation, 

 the corresponding analytical solutions are directly applicable. Carslaw and 



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