illustrated in Figure 6) using a scrape and trowel, and initial profiles were taken. As previously stated, 

 wave rods were calibrated to ±0.002 ft tolerance prior to each test to ensure accuracy of recorded wave 

 data. As Wcis done in the prototype tests, regular waves were run in short bursts to minimize the effects of 

 re-reflection off the wave board. Irregular waves were run for times equal to the scaled equivalent of the 

 prototype wave runs. Time for water surface stilling was allowed between runs. Reflection coefficients 

 measured during the tests at the gages nearest the wave board ranged from 0.06 to 0.2, but wave height 

 variation never exceeded the ±20 percent specified for the prototype tests. 



86. Center-line profiles were taken during a test corresponding to similar profile measurements in the 

 prototype after the same number of waves. Profiles were taken along each sidewall of the flume at the 

 conclusion of each test to document observed cross-tank variations. A graduated rod with a 2-in.-diam 

 circular foot pod wcis used to obtain all center-line profiles, as shown in Figure 7. Elevations were normally 

 obtained along the profile at 0.5-ft intervals with additional elevations recorded as necessary to document 

 profile irregularities, such as the erosion scrap. A benchmark elevation was taken at the beginning and end 

 of every profile measurement to ensure that vertical elevations were consistent throughout the tests. 

 Profiles measured along the flume side walls were obtained using a surveyor's level and graduated rod. The 

 same benchmark was used for both the center-line profiles and the wall profiles so that all profiles could be 

 related to a common datum. 



Model Experiments 



87. A total of 14 tests were conducted in the 6-ft flume at CERC during the two test series 

 documented in this report. Test identification numbers, brief descriptions of each test, and reference to the 

 section of the report that discusses test results are given in Table 3. 



88. Representative results are presented in the following report sections to illustrate observed profile 

 development. Complete results are given in the report appendices. Wave analysis results for each 

 experiment are given in Appendix B, the experiment profile data are tabulated in Appendix C, the 

 experiment profile plots are in Appendix D, and comparison of profiles from different cases (model versus 

 model and model versus prototype) are shown in Appendix E. 



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