Method of Constructing Test Sections 



19. Construction of the modeled section simulated prototype construc- 

 tion as closely as possible. The base, core, and secondary armor layers were 

 each placed by dumping from a shovel or bucket to the predetermined grade 

 level. Hand trowels were used to smooth and compact the core material to 

 simulate natural consolidation which would result from wave action during 

 construction of the prototype breakwater. The primary armor layer was placed 

 by hand in a random manner below mllw. Random placement consists of selecting 

 a stone at random and placing it in contact with adjacent stones on the struc- 

 ture, with no attempt to orient the axes of the stone or key the stone to the 

 structure. The placed stone method was used for armor units above mllw. A 

 small group of stones were randomly selected, and placement was made by 

 choosing the stone that would best fit the next position in the armor layer. 

 No attempt was made to key the stone into the structure to any greater extent 

 than would be feasible during prototype construction. 



Method of Determining Damage 



20. The number method was used to determine damage to a test section. 

 The number of armor units displaced from a test section was counted and 

 expressed as a percentage of the total number of armor units placed in the 

 section before testing. The section was considered "not damaged" if the dis- 

 placed stone count was less than 2 percent of the total number of units in the 

 section. 



21. The stability of the test sections could be calculated from the 

 test results by 



J^ (2) 



w a (s a - i) J cot e 



where 



K d = stability coefficient 

 7 a = unit weight of the armor units 



12 



