" Eighty-five-foot" Tank , - This indoor, reinforced concrete 

 tank is 85 feet long, 14 feet wide, and 4 feet deep. One side is 

 equipped with six glass windows, each 24 x 40 inches, spaced on 10- 

 foot centers. Each window has etched scales graduated to hundredths 

 of a foot. The tank is equipped with a steel-framed instrument and 

 personnel carrier which covers the full tank width and runs on tracks 

 along the entire tank length. Its load capacity is approximately one 

 ton (see Figure 6). 



The wave generator (Figure 7) is a steel-scoop-shaped 

 bulkhead with rollers at the bottom driven through two drive shafts 

 by a 7-1/2 hp vari-drive motor. The vertical and horizontal movement 

 of the bulkhead is independently controlled by m.eans of double 

 eccentrics located at each end of the drive shafts. Variation of the 

 eccentricities of the driving arms permits a continuous range of wave 

 heights from to about 1 foot; wave periods may be continuously varied 

 from 0.5 to 9.8 seconds by use of the vari-drive motor and a geared 

 transmission. 



A wave absorber consisting of layers of staggered cinder 

 blocks covered with wire mesh is set at an angle of 60° with the 

 horizontal at the extreme rear of the tank a few feet behind the wave 

 generator. 



The tank is also equipped with a manually operated tidal 

 system (operated through a constant head tank) which can provide a 

 complete tidal cycle with a maximum 12-inch fluctuation in 40 minutes 

 (or 6-inch fluctuation in 20 minutes, etc.). Stilling well connections 

 at the tank sides permit measurement and control of tidal fluctuations. 



Shore Processes Test Basin . - This outdoor, reinforced 

 concrete tank is rectangular except that 50-foot triangular sections 

 are omitted on two corners (see Figures 1, 8, and 9). Horizontal 

 dimensions are 150 x 300 feet, and the depth is 3 feet. The tank is 

 presently subdivided with a removable concrete wall into two basins, 

 100 x 150 feet, and 200 x 150 feet. 



Movable wave generators of the push-pull bulkhead type, 

 nine with bulkhead face widths of 20 feet and one with a width of 15 

 feet, are available. Each is powered by a 7-1/2 hp A.C. variable- 

 speed electric drive and is equipped with an 8-inch variable eccentric 

 arm for changing the wave height. The machines were designed to 

 give a continuous range of wave heights up to about 8 inches with a 

 period, range of 0.8 to 4.0 seconds in 2-1/2 feet of water. Although 

 somewhat larger periods can be generated} wave heights of 8 inches 

 cannot be obtained with periods greater than 4 seconds. The machines 

 may be divided into two sets which may be operated independently to 

 produce simultaneously two separate wave trains of completely 

 different characteristics. The wave machines may also be operated 



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