APPENDIX 



EXPERII-ffiNTAL PROCEDURES FOR 71Y-06 and 71Y-10 



This appendix docioments those aspects of the experimental procedures 

 unique to experiments 71Y-06 and 71Y-10. The procedures common to all 

 experiments are documented in Volume I (Stafford and Chesnutt, 1977). 



1. Experimental Layout . 



At the beginning of the 1971 experiments, the movable-bed profiles 

 were constructed with sufficient sand to move the initial SWL intercept 

 7 feet closer to the generator. Because the initial SWL intercept on the 

 movable bed is the standard reference point, the tapes along the center 

 of each pair of tanks were moved to establish the new origin 7 feet 

 seaward of the origin used in experiments 70Y-06 and 70-10 (Chesnutt and 

 Stafford, 1977) . This resulted in a 7-foot offset of the origin in the 

 fixed-bed tanks. Figure A-1 shows the position of the initial profiles 

 within each pair of tanks and the adjusted x-axis. 



2. Data Collection , 

 a. Regular Data . 



(1) Wave Height Variability . During the first 10-minute run of 

 each experiment and from 375 to 375:10 hours in experiment 71Y-06, a con- 

 tinuous water surface elevation was recorded at station 25 near the toe 

 of the movable-bed slope (Fig. A-1). Wave envelopes in all subsequent 

 runs were recorded with wave gages moving toward and away from the gen- 

 erators along the center of each tank from station +15 to +85 in experi- 

 ment 71Y-06 and +15 to +50 in experiment 71Y-10 with the instrument 

 carriage moving at a near-constant speed of 10 feet per minute. Wave 

 records 002 to 006 from experiment 71Y-06 contain only one envelope because 

 the runs were too short to permit recording of two envelopes. 



(2) Breakers . Table 3 indicates the times during runs when 

 breaker data were collected, which included taking 35-millimeter slides 



of the breakers three times during each run, recording the breaker position 

 in the logbook just before the end of each run, and preparing the visual 

 observation form near the end of each run. The first two procedures were 

 used throughout the two experiments and the use of the visual observation 

 form was initiated 18 August 1971, at 78 hours in experiment 71Y-10 and 

 140 hours in experiment 71Y-06. 



Unlike the two experiments in 1970, the carriage and camera locations 

 were not maintained at the same positions throughout the tests; therefore, 

 the slides were not useful for determining breaker position. Since the 

 breaker station recorded in the logbook was the position along the center- 

 line of the tank, lateral variations in breaker positions were not recorded. 

 The visual observation form was used to sketch the breaker position 



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