3. Prototype Tests . 



Two prototype overlay tests were conducted in the large wave tank. , 

 The riprap underlayer for these two tests was Sioux quartzite quarrystone 

 with a median weight of 3 pounds (1.4 kilograms). Between the riprap 

 underlayer and the core of the embankment there was a crushed stone filter 

 layer 6 inches (15.2 centimeters) thick, using stone with a median diameter 

 of 1.5 inches. The core was compacted bank-run soil. Details of the large 

 v\?ave tank test section are shown in Figure -5. 



24 



Top of Side Boords 



iL 



- Bank -Run 

 Soil Core 



^ 







Top of Tonk Wal 1 



Riprop Underlayer.'---^^'^~^5::^^^i^,^^ 



Crushed Stone Filter''^ ^"^^ 





3 



^^ 



N^--/SWL^ 







Scale (ft) 





Generofor ^ 





Blade 418 ft 



Figure 5. Details of larj 



10 20 



e wave tank test section. 



Test L-1 determined the stability of the lOO-pound (45 kilograms) 

 median weight Sioux quartzite quarrystone overlay. The largest overlay 

 quarrystone weighed 290 pounds (132 kilograms); the smallest, 2Q pounds 

 (9.1 kilograms). This 100-percent overlay was tested for a 3.67-second 

 period wave with a 15-foot Stillwater depth in the tank. Wave heights 

 ranged from 2.8 to 3.8 feet (0.85 to 1.16 meters). A total of 100 wave 

 bursts with 19 waves per burst were run at each height. 



Test L-2 evaluated the stability of a 100-percent overlay of Sioux 

 quartzite quarrystone with a median weight of 209 pounds (95 kilograms) . 

 The largest overlay quarrystone weighed 675 pounds (306 kilograms) ; the 

 smallest, 100 pounds. The water depth was 15 feet and a 4.2-second wave 

 period was tested. Wave heights ranged from 3.2 to 4.4 feet (0.98 to 

 1.34 meters). A total of 100 wave bursts with 14 waves per burst were 

 run at each height. In the large tank the wave height was increased in 

 increments of from 0.3 to 0.4 foot (9.1 to 12.2 centimeters) between runs. 



The large wave tank testing at prototype scale was done to determine 

 what corrections were needed for the small-scale test results to make the 

 small tank test representative of prototype conditions; i.e., determine 

 scale effects. Large tank test photos of the 100-percent quarrystone over- 

 lay (W5Q = 100 pounds) are shown in Figure 6. 



III. ANALYSIS OF TEST RESULTS 



Changes in the embankment profile were observed from the survey data 

 collected after each run. These changes were converted to a volumetric 



14 



