RESEARCH FACILITIES AND SPECIAL EQUIPMENT OF THE 

 BEACH EROSION BOARD 



Coastal processes research facilities are of 

 interest to coastal engineers, both from the 

 standpoint of those available in general and 

 also what is available at a particular installa- 

 tion. Since the research facilities at the 

 Beach Erosion Board have been altered or enlarged 

 considerably since publication of the latest 

 description, this article has been compiled by 

 George W. Simmons, Engineering Technician, Research 

 Division, Beach Erosion Board, to provide an up-to- 

 date description of these facilities. 



The major research and development facility at the Board is 

 the research laboratory which contains experimental wave tanks, a 

 wave and tide basin, analytical equipment, and instrumentation used 

 in beach and wave studies. Also available are mobile equipment jind 

 portable instruments for field studies on the open coast. 



The layout of the buildings and wave tanks on the Beach Erosion 

 Board grounds is shown in Figure 1. The wave tanks are described 

 below and a summary of their descriptions and capabilities is given 

 in Table 1. 



Ripple Tank . - This tank has a basin constructed of 1/2- 

 inch clear plastic. Its interior dimensions are: length, 4 feet; 

 width, 3 feet; and depth, 4 inches. Waves, or ripples, having a 

 frequency of about 8 cycles per second, are generated at one end and 

 act as lenses to focus light rays from beneath the tank onto a ground 

 glass screen placed above the tank. The wave crests appear as lines 

 of light which may be photographed to record the horizontal position 

 and configuration of the waves in the tank at any time. This tank 

 is especially useful as a demonstration device and in determining 

 qualitatively the wave refractive, diffractive, and reflective 

 characteristics of various natural and man-made shore features ' (see 

 Figure 2). 



" Ninety-six-foot" Tank . - This tank is constructed of 

 steel except for an 18-foot section at the end opposite the generator. 

 This section is constructed of 3/8-inch glass to permit tests in the 

 tank to be observed and photographed from either side. The tank 

 dimensions are: length, 96 feet; width, Ij feet; and depth, 2 feet. 

 The generator is powered by a 1.5-hp vari-drive unit, which, through 

 a chain drive, rotates a steel disc. A pusher arm, eccentrically 

 mounted on the disc, drives a carriage-mounted vertical bulkhead. 



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