Initial Sh oreline • 



Groin 



SCALE 



LEGEND 



Physical model 



Analytical model 



Figure 3. Comparison between experimental and theoretical shoreline 

 evolution (after Pelnard-Considere 1956) 



is set to be proportional to twice the incident breaking wave angle to the 

 shoreline. Only solutions which were similar in shape during the course of 

 time are discussed. Two different analytical solutions are presented: one 

 for which the incident breaking wave angle and the shoreline orientation angle 

 are small and one for which the wave angle is small in comparison with the 

 shoreline orientation. The governing equations (sand transport and mass con- 

 servation) are expressed in polar coordinates and solved numerically. Grijm 

 (1965) further develops this technique ^nd presents a wide range of delta for- 

 mations. Komar (1973) also presents numerically obtained solutions of delta 

 growth under highly simplified conditions. 



21. Le Mehaute and Brebner (1961) discuss solutions for shoreline 

 change at groins, with and without bypassing of sand, and the effect of sudden 

 dumping of material at a given point. Most of the solutions were previously 

 derived by Pelnard-Considere (1956), but they are more thoroughly presented in 

 Le Mehaute and Brebner' s work, especially regarding geometric aspects of the 

 shoreline change. The decay of an undulating shoreline and the equilibrium 

 shape of the shoreline between two headlands are treated. 



22. Bakker and Edelman (1965) modify the longshore sand transport rate 

 equation to allow for an analytical treatment without linearization. The sand 

 transport rate is divided into two different cases: 



13 



