Table 16 



Test Conditions and Overtopping Rates for Rubble-mound Dike 



with 1991 Profile 



Run No. 



SWL 

 ft mlw 



Wave 



Height 



ft 



Wave 



Period 



sec 



Seawall 

 Crest 

 Elev. 

 Hmlw 



Diite 

 Crest 

 Elev. 

 ft mlw 



Beach 



Elev. 



Hmlw 



Over- 

 topping 

 cfs/ft 



12 



16.6 



10.0 



13.0 



21.3 



25.4 



20.5 



0.0000 



13 



16.6 



12.7 



13.0 



21.3 



25.4 



20.5 



0.0000 



14 



16.6 



12.7 



15.9 



21.3 



25.4 



20.5 



0.0000 



15 



16.6 



11.0 



15.9 



21.3 



25.4 



20.5 



0.0000 



16 



17.6 



12.7 



15.9 



21.3 



25.4 



20.5 



0.0013 



17 



16.6 



12.7 



15.9 



21.3 



25.4 



15.4 



1 



18 



17.6 



12.7 



15.9 



21.3 



25.4 



15.4 



0.0005 



19 



16.6 



12.7 



15.9 



21.3 



25.4 



17.8 



1 



20 



17.6 



12.7 



15.9 



21.3 



25.4 



17.8 



1 



' Overtopping too low to be measured. 



Tests 14 and 15 used a peak wave period of 15.9 sec and H^^'s of 12.7 

 and 1 1.0 ft, respectively. Again there was no overtopping. 



Although there was no overtopping in Tests 12 through 15, there was 

 some splashing over the rubble mound. The quantity of splashing was too 

 small to measure. Wave runup approached the crest of the mound without 

 flowing over the crest. 



For Test 16, the swl was raised 1 ft to +17.6 ft, simulating possible sea 

 level rise. Peak period was 15.9 sec and wave height was 12.7 ft. The 

 high-water level produced an overtopping rate of 0.001 cfs/ft. 



For Tests 17 and 18, the beach in front of the seawall was removed, 

 leaving a beach elevation of +15.4 ft mlw. Still-water level was returned 

 to +16.6 ft mlw for Test 17 and +17.6 ft for Test 18. Overtopping was 

 observed in both tests but was not sufficient to measure at the lower water 

 level (Test 17). Overtopping rate for Test 18 was 0.0005 cfs/ft. 



For Tests 19 and 20, the beach was partially restored to an elevation of 

 + 17.7 ft mlw. The still-water level was set at +16.6 ft mlw for Test 19 and 

 raised to +17.6 ft for Test 20. Overtopping was observed in both tests, but 

 was not measurable. 



There was no armor instability in any of the tests in this test series. 



Chapter 5 Revere Dike Study 



51 



