If equation (2) is solved for p = Q.Q0.5, K^ = 1.628 indicating that 



Q ^ is the overtopping rate for a runup about 63 percent greater than 



Rg." Q will be referred to as the peak overtopping rate. 



The Appendix is a FORTRAN subroutine which calculates C^, Q^,, CL ^, 

 Qj^/CL, and Q ^/Qm to illustrate how the above procedure can be program- 

 ed and applied to any situation which might occur. 



************** EXAMPLE PROBLEM i************** 



This example is based on the example worked in SPM (Sec. 7.22), 

 modified to account for the irregularity of natural wave and runup con- 

 ditions. 



GIVEN : An impermeable structure with a smooth slope of 1 on 2.5 is 

 subjected to waves having a deepwater height H' = 5 feet and a period 

 T = 8 seconds. The depth at the structure toe is dg = 10 feet and the 

 structure elevation is 5 feet above Stillwater level (SWL) . Onshore 

 winds of 35 miles per hour are assumed. 



FIND : Estimate the overtopping rate for the given wave. 



SOLUTION : The wave height and period given are assumed to be the sig- 

 nificant values; therefore, the runup obtained in the example is the 

 significant runup, Rg. Using the following values, as given in the 

 example in SPM, 





a 



= 



0.08 











% 



= 



0.035 











% 



= 



(H<;)s - 



5, 



,0 



feet 



h 





= 



0.294 ; 









and 



solving equations (3) and (4) for Q^, gives 



Qj, = 2.70 cubic feet per second per foot 



as compared to the value obtained in SPM of 



(^ = 5.1 cubic feet per second per foot 



for monochromatic waves. Thus, the irregular wave overtopping is 

 about one-half of the value given by the monochromatic wave procedure. 

 The peak value of the irregular wave overtopping is 



Qq _ 5 = 7.2 cubic feet per second per foot , 



