227. It is interesting to note that the erosion and accretion events 

 plotted in Figure 10 are well separated by the simple criterion H/wT = 2 . 

 This value is of the same order of magnitude as that found by Wright and Short 

 (1984) in use of their large field data set and the fall speed parameter 

 evaluated at the breaker line (Table 3). The LWT data do not separate well 

 (Figure 6) by use of only this single parameter, however, and additional 

 unambiguous field data are required to further investigate this point. The 

 profile surveys should encompass the full active profile to allow checking of 

 sand conservation. 



228. In succeeding sections, discussion and analysis are again directed 

 toward profile change produced by regular waves in LWTs , unless noted 

 otherwise . 



Shoreline movement 



229. If shoreline retreat/advance is analyzed instead of bar/berm 

 profile type or global erosion/accretion, a less clear distinction is obtained 

 when only dimensionless fall speed and deepwater wave steepness are used. In 

 this case, incorporation of the initial beach slope increases predictability 

 of the criterion because the initial slope is closely related to the amount of 

 material that moves before equilibriiom is attained. Also, a gentler slope 

 dissipates more incident wave energy because the waves travel a greater 

 distance in the surf zone before reaching the shoreline. Some CRIEPI cases 

 showed that shoreline advance occurred for situations with a gentle initial 

 slope even if considerable erosion took place in the surf zone to produce a 

 distinct barred profile. 



230. Figure 11 plots shoreline retreat and advance that occurred in the 

 CE and CRIEPI experiments, together with a line distinguishing the two types 

 of response. The initial profile slope was included in the numerator of the 

 nondimensional fall speed to increase predictability. The equation of the 

 line in Figure 11 is H^L^ = 0.44 (tan/3 HywT)^"^ . 



Application to small-scale data 



231. The dimensionless sediment fall speed and the deepwater wave 

 steepness were also used to classify the data pertaining to small-scale 

 laboratory profile change found in the experiments performed by Rector (1954), 

 Iwagaki and Noda (1963), and Nayak (1970). As seen from Figure 12a, the 



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