c 



— ^ = exp(M Y) (31) 



where Y is the elevation above the bottom (feet) and C Q in lb m /ft 3 (as 

 previously determined by Kalkanis (1963)), and M in ft" 1 are given by 



/0.618 g h ) 



c ° ' VdTCf (32 > 



M = 11.53 U -18.45 



(33) 



For the equations above, q b is computed from previously presented methods and: 

 U = average flow velocity, ft/sec 



u,,,^ = maximum near-bottom horizontal particle velocity, ft/sec 

 d = mean grain diameter, ft 



18 . Other researchers have used field data to develop equations that 

 relate suspended sediment concentrations to relative wave height. Based on 

 field data obtained near Price Inlet, South Carolina, by Kana (1978) , 

 suspended sediment concentrations can be adequately described by 



Locr 10 (SS 10 ) = 2.02 - 2.of-^l (34) 



where 



SS 10 = suspended sediment concentration at 10 cm above the bed, lb^ft 3 

 h b = depth of water at point of wave breaking, ft 

 H b = breaking wave height, ft 



Other controlling factors included distance relative to the wave breakpoint, 

 beach slope, and deepwater wave height. It was found that mean suspended 

 sediment in the breaker zone correlated well with beach slope and reached a 

 maximum a few yards landward of the breaker line, and for the range of beach 

 slopes studied (0.004 to 0.04) the following relationship was developed 



Log 10 (SS 10 ) = 1.425 + 14.5 m (35) 



where m is the beach slope given by the decimal fraction of rise over run. 



21 



