An analysis similar to that for structures located seaward of the still- 

 water line gives for the dynamic pressure, 



wv'' wd. 



The dynamic pressure is assumed to act uniformly over the height h, 

 hence the dynamic component of force is given by, 



wd.h^ / x,\3 



and the overturning moment by. 



h' 



fduhl 



Mm = Rm ^ = -^- U 1 (7-98) 



The hydrostatic force component is given by. 



2 2 



wh' 

 R = -— = ^- 1 (7-99) 



and the moment resulting from the hydrostatic force by, 



h' Wh3 / X \3 



M, = R - = 1 (7-100) 



The total forces and moments are the sums of the dynamic and hydrostatic 

 components; therefore, as before, 



R, = R^ + R, (7-101) 



t m s ^ ■" 



and, 



(7-102) 



The pressures, forces and moments computed by the above procedure 

 will be approximations since the assamed wave behavior is simplified. 

 Where structures are located landward of th'i Stillwater line the preceding 

 equations will not be exact, since the runup criterion was assumed to be 

 a fixed fraction of the breaker height. However, the assumptions should 

 result in a high estimate of the forces and moments. 



7-161 



