Elapsed Time (hr) 



Figure 8. Growth of maximum bar height Zg through time 



Depth at the bar crest 



54. Depth at the bar crest h c was almost constant throughout a run, 

 as seen in Figure 9. In some cases, h underwent an abrupt change (for 

 example, Case 200), caused by a second bar located inshore that grew and 

 merged with the main breakpoint bar. Thus, although main breakpoint bars 

 moved considerably offshore, they simultaneously grew in size, with the result 

 that the depth at the bar crest remained unchanged. Even the test with a 

 varying water level (Case 911) showed an approximately constant depth over 

 the bar crest during the course of the run, indicating that there was little 

 time lag between the change in water level and response of the profile. In 

 Figure 9, h appears to vary for Case 911 because of the use of a fixed 

 origin that was located at the initial still-water shoreline. 



Bar location and movement 



55. For cases that exhibited significant erosion, the main breakpoint 

 bar usually translated offshore with time. As a convenient measure of the 

 location of the main breakpoint bar, the position of the bar center of mass 

 with respect to the initial still-water shoreline was calculated. Figure 10 

 displays the horizontal location of the bar center of mass as a function of 



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