Design Problem preliminanji Desi gn 



Pcqe no : 

 Colculaled by 

 Checked by; 



Date. 



34 oi 153 

 J. R. W. 

 R.f7.T 



/5 Mar. 73 



Diffraction Analysis (cont)_ 



Change In wove height as }vave moves into 

 deeper water around breoKwater. 



)Nqv& height (d = 5G ft.) = /// = /4.^ft 





^^ = 0.Z5I 



223 



From Appendix C, Table C-i^ t^ith^ ^o.ZSl 



La 



M = 0.9317 

 Ho 



Ho'^ -^^ = f6.0 ft. 

 0.'P3Z7 



From Appendix (T, Table C- 1, with ^^i^.o.4i5 



no 



^(d^lOGftr 0.9&t3(lG.O^--1S.& ft. 



This IS the change in wave height 

 caused only by shoaling effects as the 

 wove moves from a depth , d^S^ft. to a 

 depth, d^ioc ft 



Distance of point A from breakwater at is 

 in wave lengtti units. L'^ Lo^ 2.7.3 ft. 



y^ 20 •^ 2 7 wavelengths 



Reouired diffraction coefficient to 

 reduce wove height to 3 ft. 



This assumes no reflection of waves in 

 harbor. If perfect reflection occurs, required 

 K'^ 0.190/Z ^ 0.09S 



Appendix C 

 Table c-1 



Appends C 

 Table C-i 



8-94 



