A FEASIBILITY STUDY OF A WAVE-POWERED DEVICE FOR MOVING SAND 



by 



Frederick F. Monroe 

 Research Division, Coastal Engineering Research Center 



I GENERAL 



I . I ntroduct ion 



A model of a wave-powered sand-moving device, suggested by the 

 staff of the U. S. Rubber Company Research Center, was tested for its 

 feasibility as a device for moving sand toward shore, at the U. S. Army 

 Coastal Engineering Research Center, Washington, D. C. from I Jaunary 1964 

 to 15 March 1965. The purpose of the series of tests was to determine 

 whether the model operated sufficiently well to justify further testing 

 in the prototype or at very large scale. It had been suggested that a 

 successful prototype would provide an economical means of moving sand from 

 offshore through water too shallow for standard floating dredge operation 

 to the beach area itself, or to within reach of a beach-based, permanently 

 placed suction line, or dragline. 



The possibility existed that such a device could be useful in the 

 general program of proposed beach improvement around the shores of the 

 United States and other areas, particularly if offshore sand deposits, 

 presently being sought, proved to be of sufficient size and quality to 

 warrant their being used as borrow areas for beach replenishment. If 

 practicable, nearshore sources could provide sand for beach nourishment 

 or possibilities might exist that an ocean-going dredge could unload within 

 the reach of the wave-powered sand-moving device which would then transfer 

 the sand to the surf zone. Although the use of devices such as modified 

 amphibious military craft have been proposed for this purpose, the develop- 

 ment of an economically operated and soundly engineered machine has remained 

 eluslvely beyond the reach of existing technology. An additional benefit 

 to be derived from the use of a wave-powered sand-moving device is that it 

 would use naturally available energy to move considerable sand quantities 

 to shore, except for the winching and emplacement phases of operation. 



2. Description of Device 



The model wave-powered sand-moving device used in this study was 

 shipped to the Coastal Engineering Research Center on 28 October 1964 by the 

 U. S. Rubber Company, which had done considerable preliminary development 

 and testing. The initial development of the device is covered in a report 

 by Rhodes.'*^ This model, as received, consisted of two flotation pads compose 

 of synthetic closed-cell rubberoid foam, located fore and aft, and attached 



^Rhodes, T. J., Memorandum on Wave-Dredging Systems, United States Rubber 

 Company Research Center, Wayne, New Jersey, March 4, 1963. 



