Hughes (1983) , and Hallermeier* for movable beds by modeling large-scale tests 

 of Saville (1957) . Sand sizes modeled in the laboratory cannot usually be 

 scaled the same as distances and lengths because grain sizes with mean 

 diameters less than 0.08 mm become cohesive and behave as clay and silt. The 

 scaling relationships give distorted scales; that is, the horizontal and 

 vertical scales are not the same, to compensate for larger sand sizes. The 

 distorted scales gave initial slopes as steep as 1:3.9. Sand, coal, and glass 

 beads were used as model sediments in the Fowler and Smith study, but only 

 tests conducted with sand that resulted in erosional bar formations were 

 analyzed to determine bar angles. The small-scale cases analyzed in the 

 present study consisted of sand sizes of 0.22 and 0.40 mm, and wave heights 

 ranging from 5.0 to 9.5 cm. 



101. The three predominant angles defined by Larson and Kraus (1989) 

 were also found to be present in the smaller tank tests. The average angle 

 for each group was calculated in the same manner as Larson and Kraus to deter- 

 mine /^ , fi 2 > and Pz • Average /9 X was 20 deg, ranging between 4 and 

 37 deg. Average /3 3 was 8 deg and ranged between and 14 deg. A 0-deg 

 angle indicates a terrace bar system (Figure 26). Average /9 2 was 6.5 deg. 

 The steep seaward angles produced in the small-scale study were a result of 

 the steep initial slopes. 



Figure 26. Sketch of terraced bar 



R. G. Hallermeier, 1984, "Unified Modeling Guidance Based on Sedimenta- 

 tion," Unpublished paper, US Army Engineer Waterways Experiment Station, 

 Coastal Engineering Research Center, Vicksburg, MS. 



67 



