LABORATORY EFFECTS IN BEACH STUDIES 
VOLUME VI. MOVABLE-BED EXPERIMENTS 
WITH H/Lo = 0.004 
by 
Charles B. Chesnutt and Robert P. Stafford 
I. INTRODUCTION 
1. Background. 
Standing waves in movable-bed profile experiments can affect the 
transport of sediment and alter the development of the profile, 
particularly when the reflection coefficient is large. In addition, 
critical combinations of tank width and standing wave envelope length 
appear to generate circulation cells between wave envelope antinodes. 
The Laboratory Effects in Beach Studies (LEBS) project was initiated 
at the Coastal Engineering Research Center (CERC) in 1966 to investigate 
the causes of wave height variability and other problems associated 
with movable-bed coastal engineering laboratory studies. Ten movable- 
bed laboratory experiments were conducted from 1970 to 1972 in the CERC 
Shore Processes Test Basin (SPTB) to measure the variation in reflection 
as the profile developed toward equilibrium. These LEBS experiments 
are reported in a series of eight volumes. This report (Vol. VI) 
describes the two experiments conducted with H)/Lo = 0.004. Volumes 
II, III, and IV (Chesnutt and Stafford, 1977a, 1977b, 1977c) discuss 
the experiments conducted with H,/L, = 0.021; Volume V (Chesnutt and 
Stafford, 1977d) discusses the experiment with H,/L, = 0.039. The last 
two experiments are discussed in Volume VII. Volume I of the series 
(Stafford and Chesnutt, 1977) discusses the contents and primary 
purposes of these reports. Volumes II and III in this series describe 
four experiments with an initial slope of 0.10 and wave steepness of 
0.021. Those experiments were conducted primarily to (a) relate the 
variation of wave height to the variation in wave reflection caused by 
changes in the movable-bed profile; (b) examine the approach to 
equilibrium profile shape, on the assumption that wave height variability 
would be significantly reduced when the profile was at equilibrium; and 
(c) examine the effect of tank width by running identical experiments 
in tanks 6 and 10 feet wide. 
The two experiments discussed in this study were a direct consequence 
of the earlier experiments. All controllable variables in these experi- 
ments are the same as the variables in Volume III, except that the wave 
steepness was reduced to 0.004 in an attempt to determine how much the 
wave reflection and the reflection variability would be increased by a 
longer wave on the same initial profile. 
2. Experimental Procedures. 
The experimental procedures used in the LEBS experiments are describ- 
ed in Volume I, which provides the necessary details on the equipment, 
