ee ———E——————————E 
SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) 
wave envelope, a distance approximately twice the tank width. This current 
pattern in the 6-foot tank began to disintegrate after about 70 hours. 
The profile in the 6-foot tank was still changing at 135 hours 
when the experiment ended; in the 10-foot tank, the profile had reached 
approximate equilibrium after 25 hours. In the 6-foot tank, the foreshore 
eroded throughout the test, but in the 10-foot tank it quickly stabilized. 
In the 6-foot tank, the offshore consisted of an almost flat shelf and a 
steep seaward slope as long as the circulation prevailed, but became more 
gently sloping after the circulation disappeared. In the 10-foot tank, the 
offshore was less steep and stabilized after about 50 hours. 
Reflection coefficient, K,, varied from 0.17 to 0.31 in the 6-foot tank, 
increasing as the shelf developed during the time of active circulation. Kp 
then began decreasing as the steep offshore slope began flattening. In the 
10-foot tank, Kp was higher, varying from 0.24 to 0.37 and tended to increase 
with steepening of the foreshore. 
2 UNCLASSIFIED 
SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) 
