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depending on calculated velocity head. The angular width of the front maximum 

 depends on channel geometry of the pile, tending to be very broad for a pile 

 without channels and narrow for a pile with deep channels. With H-piles having 

 deep channels, the pattern minimums occur farther forward than with unchanneled 

 piles. Geometrically similar piles of different size result in similar patterns 

 The patterns for finned and smooth circular piles are similar, except that the 

 finned pile results in slightly higher and narrower front and rear maximums. 



Applications of the reported conclusions to the design of nearshore pile- 

 supported structures are briefly discussed. 



Twelve different vertical piles were tested, including circular, circular 

 with radial fins, and various H-sections, Pile cross section and water depth 

 were small compared to wavelength, corresponding to typical nearshore 

 situations. Electrical gage records and photos show complicated surface 

 effects occur near the piles. Crest stagnation can be similar at circular and 

 channeled piles with three stagnation regimes: smooth, breaking, and jetting 

 runup. Smooth runup occurred in most tests, with a nonbreaking bow wave formed 

 at the front of the pile during peak forward flow. 



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