D . 3.7 t 5f^ = 9.2 feet 



z' fir- ■ -"IS -■» i^ ■•"55 



Therefore 



Lj3 = 9. 2/. 055 = 167 feet, 



14.80, The total dynamic pressixre if the groin were normal to the 

 direction of wave approach would be determined from equation 1^7 or 



p - TTg 2.8 X 6h.2 ^ 3.7 (9.2 + 3.7) 

 ^ra " 1^7 ^ 9.2 



P = 109 X 5.2 = 567 pounds per Square foot, 



and the static pressure is 



_ wH 61i,2 X 2.8 __ , „ . 



?=•«—= « : — = 90 pounds per square foot. 



These pressures xtouM be applied in a manner similar to that shown in 

 Figure lli8o 



14.81, The total maximum wave pressure if the groin xjere nomal to 

 wave approach by equation (6) would be 



P^ = (567 X ^) + 90 (3.7 + ^) 



= 530 + 396 = 926 pounds 



As the dynamic pressure acts at an angle (OC ) with the structure, iiie 

 total force normal to the structure per unit length of structure would 

 be, with Of = 30 degrees. 



P^ = 530 sin^ Of + 396 



= 133 + 396 = 529 pounds oer foot of groin. 



I(.82, The moments around the base of tie block by equation (l59) would 



be 



M= 133x3.7. 21±Ilf. ^ iiL£_M (3.7-^.7) 



M = U92 + 616 + 528 = 1636 foot-pounds, 

 228 



