REPORT DOCUMENTATION PAGE 



Form Approved 

 OMB No. 0704-0188 



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 for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway. Suite 1204. Arlington. VA 22202-4302. and to the 

 Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington. DC 20503. 



AGENCY USE ONLY (Leave blank) 



2. REPORT DATE 



September 1994 



REPORT TYPE AND DATES COVERED 



Final report 



4. TITLE AND SUBTITLE 



Investigation of Wave Grouping Effects on the Stability of Stone- Armored, 

 Rubble-Mound Breakwaters 



6. AUTHOR(S) 



Robert D. Carver, Brenda J. Wright 



5. FUNDING NUMBERS 



WU 32534 



7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 



U.S. Army Engineer Waterways Experiment Station 

 3909 HaUs Ferry Road, Vicksburg, MS 39180-6199 



PERFORMING ORGANIZATION 

 REPORT NUMBER 



Technical Report CERC-94-13 



SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 

 U.S. Army Corps of Engineers 

 Washington, DC 20314-1000 



10. SPONSORING/MONITORING 

 AGENCY REPORT NUMBER 



11. SUPPLEMENTARY NOTES 



Available from National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. 



12a. DISTRIBUTION/AVAILABILITY STATEMENT 



Approved for public release; distribution is unlimited. 



12b. DISTRIBUTION CODE 



ABSTRACT (Maximum 200 words) 



High sea waves tend to appear in groups rather than individually. Because of the nature of wave grouping, it appears that 

 it may be an important influence on the stability of rubble-mound structures. The research documented in this report was 

 conducted to obtain a better understanding of the effects of wave grouping on the stability of stone armor when used on 

 breakwater trunks. Results of this study show stability to be influenced by wave period, spectral width, and wave grouping 

 intensity. Levels of wave grouping tested herein are achievable at some, but not all, prototype locations; therefore, results 

 should be applied on a case-by-case basis. 



14. SUBJECT TERMS 



Armor stability 

 Breakwater 

 Stone armor 

 Wave grouping 



15. NUMBER OF PAGES 



48 



16. PRICE CODE 



17. SECURITY CLASSIFICATION 

 OF REPORT 



UNCLASSIFIED 



18. SECURITY CLASSIFICATION 

 OF THIS PAGE 



UNCLASSmED 



19. SECURITY CLASSIFICATION 

 OF ABSTRACT 



20. LIMITATION OF ABSTRACT 



NSN 7540-01-280-5500 



Standard Form 298 (Rev. 2-89) 



Prescribed by ANSI Std. Z39-18 

 298-102 



