Type of Stone 



Weight, tons 



Percent by Weight 



W 



10 



30 





12 



30 





14 



30 





16 



10 



W/2 



5 



33 





8 



33 





10 



34 



W/3 



3 



25 





5 



25 





8 



25 





10 



25 



Transmission tests of Plans 1. 1A, and 1A1 



Initial tests consisted of checking the transmission response of Plan 1 

 (Photos 1-3). Three prototype spectra were selected for verification of the 

 model breakwater. Characteristics of the chosen prototype spectra were as 

 follows: 



T p , sec 



Hf,H 



H r ft 



C t 



7.1 



9.2 



1.4 



0.15 



9.2 



6.6 



1.1 



0.17 



11.6 



15.6 



3.6 



0.23 



The first attempt to reproduce the desired wave conditions in the model 

 yielded the following results: 



T p . "C 



Hf.it 



H r H 



C t 



7.0 



7.2 



0.8 



0.11 



9.0 



6.0 



0.9 



0.15 



11.8 



17.0 



3.7 



0.22 



Peak periods of these spectra are in good agreement with the prototype; 

 however, both the incident and transmitted wave heights are low for the 7- 

 and 9-sec periods and most importantly, the amount of energy transmitted 

 through the structure is low for these periods. Therefore, it was decided to 

 attempt to increase the porosity of the structure by rebuilding the armor in a 

 more random manner (Plan 1A shown in Photos 4 and 5), increase the energy 

 levels of the 7- and 9- sec spectra, decrease the energy level of the 11 .8-sec 



Chapter 3 Tests and Results 



