Approach 



3. Model breakwaters and armor units are used to experimentally in- 

 vestigate the stability response of various armor combinations for selected 

 structure geometries and wave conditions. It would be an extremely extensive 

 task to comprehensively investigate all different types of existing armor 

 units; therefore, this research effort will address only the three types 

 (stone, dolos, and tribars) of armor most commonly used in the Corps. Selec- 

 tion of these armor types should give test results the widest range of appli- 

 cability possible. Tests will be conducted with breaking wave conditions on 

 no-damage, no-overtopping breakwater trunk and head sections by using sea-side 

 slopes of IV on 1.5H and IV on 2H. 



Purpose of Study 



4. The purpose of the present investigation was to obtain design guid- 

 ance for dolos and tribar overlays used to rehabilitate stone-armored 

 rubble-mound breakwater and jetty trunks subjected to breaking waves. More 

 specifically, it was desired to determine the minimum weight of individual 

 armor units (with given specific weights) required for stability as a function 

 of the type of armor unit, sea-side slope of the structure, wave period, wave 

 height, and water depth. 



