PART II 

 STRUC-TOML DESIGN 



SCOPE 



193.- The first part of this section, PHYSICAL FACTORS, contains general 

 data pertaiiij.ng to design and includes: methods for determining wave heights 

 and forces I earth and ice forces and their points of application^ and certain 

 considerations of materials of construction coramonly used in shore protective 

 works J The second pai-t contains solutions of typical problems of design of 

 protective measures s 



PHYSICAL FACTORS 



V7AVE HEIGI-rrS 



19lj-= D eterrnination of iBsignWave Height and Direction ^ - If econoinically 

 feasible, any structiu'e exposed to wave action should be designed to with- 

 stand the effects of the highest wave to be exoected at the structure's loca- 

 tion* Visual observations of storm waves are usually unreliable * Direct 

 measurement is costly and time consiunings General procedures for developing 

 the height and direction of the design xirave by use of refraction diagrams 

 are described in the following paragraphs.. 



19^^ Significant Design Wave - Structure Outside the Breaker Zone , - 

 From the structure's intended location, draw a set of "refraction fans", for 

 various wave periods in increments of about 2 seconds that might be expected 

 at the site, and determine refraction coefficients hj the method given in 

 Part I« Tabulate the refraction coefficients so determined for the various 

 x^'ave periods chosen ajid for each deep water direction of approach* The 

 statistical wave data derived from synoptic weather charts or other sources 

 should then be reviewed to determine if the directions and periods for which 

 the refraction coefficients are large may be expected to recur with reasonable 

 frequency^ 



196.:. That combination of deep water wave height and refraction coefficient 

 which gives the highest wave height at the structure's location determines 

 the design wave direction of approach and period. The inshore height so 

 deternined is the significant design wave height. 



197, A tj'pical exanple of such an analysis is shown in the follox-jing 

 table . 



99 



