each berm stone weight tested, the 3-D berm crest kept a fixed length of 

 approximately 0.4 ft in the model. This difference was the result of testing 

 several berm armor stone weights in various areas on a given test section. 

 The remainder of the 3-D test sections consisted of a head and trunk section 

 of a typical multilayered, nonovertopping design armored with stone or 

 dolosse. In one instance, the test section represented an old stone structure 

 that had been overlaid with dolos armor. Photographs 6 and 7 show two 

 examples of the 3-D test sections. 



Test Conditions 



2-D and 3-D toe berm stone tests 



13. Prototype toe berm armor stones are exposed to various combinations 

 of wave conditions and water depths. The weight of individual stones required 

 for wave stability will vary greatly with incident conditions. A wide range 

 of toe berm stone weights (from the maximum weight capable of being moved in 

 the test facility to the minimum weight that can be tested outside of 

 stability scale effects (Hudson 1975)), were tested to determine the stability 

 response for toe berm stones exposed to breaking wave conditions over a wide 

 range of water depths for wave orthogonals approaching both normal (90-deg 

 angle to structure crest) and oblique (45-deg angle to structure crest) to the 

 toe berms. The foreslopes used in the 2-D tests in the 5- and 6.75-ft wave 

 flumes (IV on 10H) and the 3-D tests in the T-shaped wave basin (IV on 10H) 

 were steeper than the foreslope in the L-shaped wave basin (IV on 35H) . This 

 steepness resulted in some difference in severity of incident wave conditions, 

 with the steeper foreslope producing more severe plunging waves than those 

 produced by the milder slope. Thus, the data derived from these tests cover 

 steep and intermediate foreslopes. 



General design guidance 



14. Specific model test conditions can be nondimensionalized for use in 

 developing general design guidance. Relative water depth at the toe d s /L s * , 

 relative water depth at top of berm d 1 /L 1 , relative wave height at the toe 

 H D /d s , wave steepness at the toe H D /L S , relative berm depth d 1 /d s , and 

 relative berm length B/L x , were thought to be major parameters influencing 



* Symbols and abbreviations are listed in the Notation (Appendix A) . 



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