(b) measure the approach of the profile to an equilibrium 

 condition; and 



(c) identify, and if possible quantify, the effects of 

 other laboratory constraints (e.g., water temperature, tank 

 width and length, and initial slope) on the resulting labo- 

 ratory profile. 



The discussion of results in Section IV of Volumes II to VII covered 

 (a) wave height variability, (b) profile equilibrium, and (c) laboratory 

 effects. This volume discusses those topics in Sections II, III, and 

 IV, respectively. The data from individual experiments are not repeated 

 in this volume, but the results from Volumes II to VII are compared to 

 develop more generalized conclusions (Sec. V) and recommendations 

 (Sec. VI). 



Definitions of coastal engineering terms used in LEBS reports conform 

 to Allen (1972) and the Shore Protection Manual (SPM) (U.S. Army, Corps 

 of Engineers, Coastal Engineering Research Center, 1977). A definition 

 sketch of typical profile zones is shown in Figure 1. The backshore- 

 foreshore boundary is at the upper limit of wave uprush, the foreshore- 

 inshore boundary at the lower limit of wave backrush (low water line) , 

 and the inshore-offshore boundary at a point just seaward of the breaker. 



Plots of contour movement (CONPLT plots) are used in all experiments 

 to show, in one figure, the changes in profile shape along a given pro- 

 file line throughout an entire experiment. An interpretation of these 

 CONPLT plots is given in Section 11,2 of Volumes II to VII. 



The LEBS data have other uses to both the laboratory and field engi- 

 neer. For example, the profile surveys, sediment-size distribution data, 

 and breaker conditions reported in Volumes II to VII, and color slides 

 of the ripple formations (available at CERC) can be used in a more 

 detailed analysis of coastal processes. The shoreline recession rates 

 from several of the experiments can be used by the field engineer, after 

 consideration of scale and laboratory effects, in determining generalized 

 shoreline recession rates. A further analysis of the profile surveys is 

 currently being conducted by CERC to determine temporal variations in 

 net onshore-offshore material transport. The profile data would be use- 

 ful in calibrating a numerical model of profile evolution. 



The LEBS reports are not an all-inclusive study of laboratory 

 effects, because several other known laboratory effects have yet to be 

 examined intensively. These reports serve as an introduction to the 

 subject of laboratory effects and as a guide to some of the problems 

 involved in performing movable-bed coastal engineering model studies 

 and research experiments. 



II. WAVE HEIGHT VARIABILITY 



The nominal (generated) wave height, Hq, in Table 1 is the height 

 of the wave traveling from the generator toward the profile unaffected 



