and, therefore, 



Hg = 0.68 H = 0.68 (10.0) = 6.8 m (22.3 ft) 



say 



n = 7 m (23 ft) 



a 



The structure supported by the pile must be 7 m (23 ft) above the still- 

 water line to avoid uplift forces on the superstructure by the given wave. 



Calculate, from equation (7-21), 

 D 1.25 



L^ 170.7 



= 0.0073 < 0.05 



Therefore equation (7-20) is valid. 

 From Figure 7-75, 



\ 



= 0.014 



2 

 gT 



H \gT / 0.0073 



= 0.52 



H, /H, \ 0.014 



From Figures 7-71 through 7-74, 



^Dm = 0-35 



Hm = 0-59 

 Sz?m = 0-79 

 From equations (7-46) and (,1-kl) ^ 



and 



TiH f o \ Tr(lO.O) 1 , , / /,, , f^/<,x 

 u = -7^ ^;— I = — V^^ — - A -ic = 3.4 m/s (11.1 ft/s) 

 max T \ L- / 12 0.76 



u D 

 mxx (3.4) (1.25) 6 



R = 4.57 X 10 



e V -7 



9.29 X 10 



7-147 



