generated in the tank. Wave Condition 1 falls on the broken waves -regular 

 wave border. Wave Conditions 11-13 indicate two and three solitons may form. 

 Condition 14 lies in the confused wave region, and Condition 15 falls on the 

 border of regular waves and two solitons. Condition 15 was examined visually, 

 and it was determined that no solitons formed. Regular waves were expected 

 for Conditions 2-9. In an effort to generate only stable waves, and also to 

 limit the total number of tests (about 100 tests) , five stable wave conditions 

 were selected with H /L - values ranging from 0.0088 to 0.09. (The maximum 

 wave steepness attainable is given by the Michell (1893) criterion H /L 

 = 0.142). The low steepness wave, Condition 15, was included to cover a range 

 in wave steepness of one order of magnitude. Condition 15 had the lowest wave 

 steepness with the highest wave height that could be generated at 1.25- ft SWL 

 without producing solitons. 



Bar Design 



98. Selection of representative bar geometry was based on results of 

 Larson and Kraus (1989) . Larson and Kraus examined morphologic features 

 produced in large wave tanks by regular waves (Saville 1957, Kaj ima et al. 

 1983, Kraus and Larson 1988). Saville conducted tests in a 635-ft-long, 

 15-ft-wide and 20-ft-deep wave tank, and Kaj ima et al. conducted tests in a 

 205-m-long, 3.4-m-wide, and 6-m-deep wave tank. Mean sand grain sizes were in 

 the range of 0.20 to 0.47 mm in these experiments. Waves were of a field 

 scale with heights reaching 1.8m, and periods were as long as 16 sec. 



99. Larson and Kraus (1989) found that the equilibrium bars formed in 

 these regular wave studies generally exhibited three predominant angles: a 

 lower seaward angle y3 x , an upper seaward angle /J 2 > ancl a shoreward angle 

 /? 3 . The area covered by /3 2 was fairly small and was a secondary angle. 

 The average seaward angle p 1 of the bars ranged between 8 to 12 deg, with 

 local slopes as great as 20 deg. The average shoreward bar angle for beach 

 profiles near equilibrium was 28 deg, and ranged from 20 to 35 deg. Average 

 secondary seaward bar angle /3 Z ranged between 4 to 8 deg. 



100. Bar geometry generated in a small tank was also examined in the 

 present study. Fowler and Smith (1986) conducted movable-bed tests in the 

 same tank used in this study. The purpose was to compare scaling relation- 

 ships developed by Noda (1972), Lepetit and Leroy (1977), Vellinga (1982), 



66 



