mated by least-square fitting of the data to an expression similar to that in 

 Equation 7 . Correlation analysis performed on the 24 values showed that the 

 equilibrium bar height was most closely related to deepwater wave height and 

 sand fall speed. If the wave height increased, the bar height increased, 

 whereas a greater fall speed implied a smaller bar height. Equilibrium bar 

 height was only weakly related to wave period, for which a longer period 

 tended to produce a smaller bar height. 



255. Regression analysis between the maximum equilibrium bar height and 

 basic wave and beach parameters, preserving dimensions, accounted for 65 

 percent of the variation in the data. The deepwater wave height and the sand 

 fall speed together accounted for 60 percent. If only bars that formed on 

 erosional profiles were considered (19 values), the coefficient of determina- 

 tion increased considerably (80 percent), for which deepwater wave height and 

 fall speed accounted for 75 percent. The dimensional regression equation for 

 the erosional cases is 



Zg = 0.128 H„^-^^ w"°-=« (12) 



256. From the regression relationship derived with dimensional quanti- 

 ties (Equation 12) it was possible to form nondimensional parameters by 

 division with the wave period raised to a suitably chosen power. The maximum 

 equilibrium bar height divided by the wavelength is a function of dimension- 

 less fall speed and deepwater wave steepness. Wave period had little effect 

 on bar height and, as mentioned previously, inclusion of the wave period may 

 increase the coefficient of determination but not the predictability of the 

 maximum equilibrium bar height. The regression equation is written 



(13) 



257. Use of nondimensional quantities in this case did not lower the 

 coefficient of determination notably (from 80 percent to 75 percent) for 

 predicting the maximum equilibrium bar height. Figure 21 shows a comparison 



Zb 





r Ho ■ 



0.59 



■ H 



— = 



= 0.122 



— 





— 



Lo 





wT 





. L 



92 



