= 5800 + 11;>600 s IT^UOO foot pounds per lineal foot of wall 



301, Forces Due to Breaking Waves. - Though the maximum deep water 

 wave breaks before reaching the wall, some lesser height wave will break 

 right at it. This wave height may be approximated by the relationship 

 d^/H^ =1,3 where d^ is the maximum water depth at the wall. In this 

 case then, H^ s 5/1.3 = 3o8 feet. To use the Minikin relationships for 

 forces, it is necessary to determine D and Lp as indicated in paragraph 

 209:' ',■ In tabular form, the computations are as follows: 



TABLE 28 - Determination of D and Ln for d » g feet 



L; Wo d/L^ L<i D D/L^ D/L^^ L^ 



Cfeet) " (feet) (feet) ~ (feet) 



737 0.0068 0,033 d -, ^o i to ' ' ^ „ o 



rTnr^ = ^52 152 +5=8.8 0.0119 O.OUU D =200 



0-033 — iio ' ,■ -oToCII .r 



302. The wave shock pressure is given by 



101 H^w , ,, ^ d ^ " ' -.,ex 



Pm = -^ xd(l H. p ) (75), 



= 101 X 3.8 X 61;. 2 X 5 A-, ^ 5 N „zo 



200 ^ 8^^^8' " ^°^ pounds per square ft. 



and the maximum hydrostatic pressure at the depth d^^ (the base) ignoring 

 any water pressure on the wall backface would be 



Pd = w (db + H) ^ ^^^2 (5 + 1.9) (76) 



= \xhh pounds per square foot. 



The manner of application of these pressures is shown in Figure 101. 



From this figure, the total thrust is given by 



R . R^ + R^ 



= Pm (^) + ^ ( d * |) (77) 



= 967 X 3^8 + 2i!2(6o9) 



_. 3 



' ' - l'' ■ *■ • 

 = 1222 > 1530 = 2752 pounds per lineal foot of wall. 



Ilt8 



