Reference Pile 



Direction of Wave Travel 



Figure 7-86. 



Definition sketch: calculation of wave forces on a group of 

 piles that are structurally connected. 



By repeating this procedure for various choices of x,, it is possible to 

 determine the maximum horizontal force and moment around the mud line for the 

 pile group. 



F (6) is an even function, and F .(6) is an odd function; hence 



and 



^D ^^^ " ^D^~ ^^ 



(7-60) 



F^(e) = - F^ (- 9) 



(7-61) 



and calculations need only be done for ^ 6 ^ it radians. Equations (7-60) 

 and (7-61) are true for any wave that is symmetric about its crest, and are 

 therefore applicable if the wave tables of Skjelbreia et al. (1960) and Dean 

 (1974) are used. When these tables are used, the wavelength computed from the 

 appropriate finite amplitude theory should be used to transform 6 into 

 distance from the wave crest, x . 



The procedure is illustrated by the following examples. For simplicity, 

 Airy theory is used and only maximum horizontal force is considered. The same 

 computation procedure is used for calculating maximum moment. 



7-151 



