PART V: DISCUSSION 



29. During construction and testing of the 2.3- and 4.0-ton dolos 

 designs it was observed that stability of the crown dolosse tended to vary 

 across the width of the test section. The dolos construction was totally 

 random and tapered out to a one-layer placement on the harbor side of the 

 crown. It was noted that if dolosse in this one-layer area were either inter- 

 locked with an adjacent dolos unit or if a fluke of the dolos projected down 

 into a void area between the armor stone, the dolos exhibited a higher stabil- 

 ity than those which ended up in a solitary position on a flat portion of the 

 crown. Based on these observations, it would appear that dolosse units placed 

 in this one-layer area of the crown are subject to easy displacement by over- 

 topping waves and they need to be keyed into the existing armor stone or 

 adjacent dolosse units. In areas where this keying of the one-layer dolosse 

 cannot be achieved, it may be a better alternative to not place a dolos unit, 

 as it will most likely be displaced during the first overtopping storm condi- 

 tion that occurs. 



30. The 9- to 20-ton armor-stone design exhibited the highest stability 

 of the plans tested, but regardless of whether it or the 4-ton dolos design is 

 selected for the proposed rehabilitation work, care must be taken to tie the 

 new protection into the existing keyed-and-f itted armor stone on the crown and 

 ends of the rehabilitation areas and the 2.0-ton dolosse in the eastern limits 

 of the new work. If a straight-line transition is used between either the 

 4-ton dolosse or 9- to 20-ton armor stone and the existing 2.0-ton dolosse, 

 this area could prove to be an area of inherent instability and may require 

 continual maintenance after storm-wave conditions. Efforts should be made to 

 interlock this area of dissimilar armor. The end areas of the new rehabili- 

 tation also could be subject to damage, especially for storm waves that 

 approach this area from an oblique angle. These areas should be constructed 

 so that a smooth transition exists from the new work into the existing break- 

 water armor. If this cannot be achieved, large buttressing stone could be 

 placed from the toe to the crown on the ends of the new rehabilitation work to 

 prevent the displacement of new dolos or armor stone when storm waves approach 

 the structure from oblique angles. 



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