



De 



sign 



Table 1 

 Wave Conditions 













TMA Spectral Parameters 





Storm Type 



H , ft 

 mo 



15.81 



13.60 







T , sec a, 

 P Y lo 



'^hl 



Hurricane 

 Northeaster 



13.7 1.1 0.0001 

 15.4 3.4 0.1300 



0.90 

 0.15 



were made to verify that the required spectra were being reproduced in the 

 wave tank at the wave board. 



Model Construction 



12. Model seawalls for overtopping tests were constructed by covering a 

 1.5-ft-wide marine plywood frame with sheet metal. For the pressure tests, an 

 additional 8-in.-wide center section was machined from aluminum block to ac- 

 commodate the six pressure transducers. Profile views of the Phase I and 

 Phase II seawalls are shown in Figures 5a and 5b, respectively. Locations of 

 the pressure transducers are also shown in Figure 5b. 



13. Figure 4 shows a plan and profile view of the tank bathymetry, gage 

 locations, overtopping basins, etc. Overtopping rates were determined by mea- 

 suring the change in water levels in two containers located behind the 

 seawall. 



14. During testing of the Phase I seawall, stability of a proposed 

 fronting stone riprap revetment was investigated. Sizing of the model stone 

 was accomplished using the following transference equation: 



Ca) (^a) 



("a) (^) 



(^ 



.) - 



p 



1 



{' 



a) - 



'm 



1 



where 



W = weight of an individual stone, lb 

 m,p = model and prototype quantities, respectively 



14 



