SHIPLAP BLOCKS 



Shiplop BlocKs 



Filter 

 SECTION 



m^ss? 1 * 





Shiplop BlocK 

 Top Perspective 



Patuxent River, Calvert County, Md. 



Prototype Installation : 



Friendship House, Patuxent River, Maryland. 

 Estimated design wave height 3 feet. 



Concrete patio blocks (8 by 16 by 2 inches) were fastened together in 

 shiplap pattern with epoxy; blocks were placed on woven filter cloth. 



Toe was buried. 



Cost about 50 percent less than riprap (Hall and Jachowski, 1964). 



Jupiter Island, Florida. 



Three- foot-square Shiplap blocks alternating 10 and 14 inches thick 

 (Wilder and Roller, 1971). 



Wave Tank Tests : 



Patio blocks (18 by 18 by 3 inches each) were fastened together with 

 epoxy and tested at prototype scale in the 'CERC large wave tank. 

 This 1 on 2 slope revetment was stable for a 4- foot-high, 6-second- 

 period wave (Hall, 1966). 



Design Factors : 



Zero-damage wave height: Depends on unit size. 



Wave runup: 0.9 to 1 compared to smooth slopes (estimated). 



Wave reflection: High (estimated). 



Remarks : 



8- by 16- by 2-inch units weigh 75 pounds. 



18- by 18- by 3-inch units weigh 150 pounds. 



36- by 36- by 10-inch units weigh 1,400 pounds. 



36- by 36- by 14- inch units weigh 1,600 pounds. 



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