Design P roblem Preliminarq Desi gn 



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Selection of Design Waves and Water Levels 



The selection of design conditions is 

 related to the economics of construction and 

 annual maintenance costs to repair structure 

 in the event of extreme v^ove action. These 

 costs* are related to the probability of 

 occurrence of extreme yvaves and high water 

 levels. There will usually be some design wove 

 height which will minimize the average 

 annual cost (including amortization of first 

 cost). This optimum design wove height \NiU 

 give the most economical design. 



^design wave height giving 

 / most economical design 

 ■*;5 \ \ ; Aotol average annual 



^ \ \ : [^ cost 



/ 



:3 



c; 



amortized 

 first cost 



maintenance 

 S repair cost^ 



Design Wave Height 



Intangible considerations such as the 

 environmental consequences of a structural 

 failure or the possibility of loss of life in fhe 

 event of failure must also enter into the decision 

 of selectina design conditions. These factors 

 are related to the specific purpose of each 

 Sitructure. 



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