conditions that will not interfere with navigation, then the selected structure 

 will be required to dissipate substantial energy on or within the structure as do 

 low-crested permeable rubble-mound structures. Such considerations can aid 

 in initial evaluation of alternative structures, but physical model studies may 

 be required for large-scale projects or to determine the performance 

 characteristics of a given structure cross section under selected design wave 

 and water level conditions. 



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Chapter 4 Structural Design Guidance 



