300» The dynamic pressure (P^^) and hydrostatic pressure at the 

 base (Pj.) are given by 



P„ = wd ( 1 . jci__)2 (71) 



and Ps » ^ ^^c - -V ('^2) 



where w ■ 62, U pounds per cubic foot = unit weight of water 



d « 10 feet a breaking depths referred to the maximum 

 water level 

 hp • 0.7 X H^ a $.25 feet s the breaking wave crest elevation 

 above the maximum water level 



hy a -5 feet = the elevation, measured povsitively upward, of 

 the wall base above maximum water level 



XI . vslope X (d + h„) = UO (10 - 5) = 200 feet ;= the distance 

 from the line of breakers to the w all 



X2 » slope (d + h(,) s 40 (10 + 5.2$) » 610 feet = the distance 

 from the line of breakers to the landward li-mit 

 of uprush 



Therefore P = *^^^ '^^ (1 - 1^) = liil pounds per square foot 

 III 2 ^ olU 



and P « 62elt (10.25)' = 6ii0 pounds per square foot 

 s 

 The pressure distribution is shown in Figure 100, From this figure, the 



total thrust R is given by 



• R =(Rd-}+ Rs 



= Pm (^c) - Ps (^^^4-^) (73) 



= 1U5 (5.25) + 658 (i°i2i) » 



- 760 * 3390 « ia50 pounds per lineal foot of wall 

 and the total moment about the base M is given by 



. =(M(%^KI) *^d(^-^) 



(7U) 

 s 760 (1|25 ^ ^) ^ 33^0 (lOii?) 



