SYMBOLS AND DEFINITIONS— Continued 



t' time required following construction until shoreline at a groin or jetty 

 reaches the end of the structure (time when sand bypassing begins) 



x distance measured generally along the shore 



y distance to shoreline measured from base line (a function of x) 



a the angle between an incident wave ray and the weir axis 



•empirical coefficient used in equation to determine wave overtopping 

 rates 



a b angle a breaking wave crest makes with the shoreline 



g empirical coefficient used in Goda's equation to predict wave transmis- 

 sion by overtopping 



At time interval 



A¥ change of sediment volume 



AVg sediment volume change on Bogue Banks, North Carolina 



A¥ sediment volume change on Shackleford Banks, North Carolina 



tan 9 

 e surf parameter given by e = . , 



/H i /L o 



e / x \ 



— factor in the argument of the error function complement E I . I 



6 angle the seaward face of a rubble-weir section makes with a horizontal 



it 3.1415 . . . 



T tidal period 



t time (interval of integration) 



10 



