III. University of California Contract DA-49-055-civ-eng-63-4, Transport 
Of Coastal Sediments. (Old Contract DA-49-055-eng-17, "Fundamental 
Mechanics of Sand Movement by Waves" ) 
Work previously carried out under Contract DA-49-055-eng-17 was con- 
tinued under a new contract, Contract DA-49-055-civ-eng-63-4, "Transport 
of Coastal Sediments". 
A report "Sand Movement by Wind" was given limited distribution by the 
University of California as Institute of Engineering Research Technical 
Report Series 72, Issue 7, and is now being published as a Beach Erosion 
Board Technical Memorandum, This report discusses earlier experimental 
results in wind tunnels of sand movement by wind, and describes and com- 
pares results obtained from new wind tunnel tests. Findings of previous 
investigators with respect to rate of sand transport were generally re- 
affirmed, but average flying distance of sand particles was found to be 
much greater, possibly due to the method of calculation. Of particular 
interest are tests on the influence of moisture content on sand movement. 
The experimental data clearly demonstrate that, as the sand moisture con- 
tent increases, the value of the threshold shear velocity of sand movement 
may also materially increase. A quantitative expression of this effect is 
obtained. A further report, "Sand Transport by Wind - Studies with 0.145 
Millimeter Sand", given limited distribution by the University of Cali- 
fornia as Institute of Engineering Research Technical Report HEL 2-5, is 
also included as an appendix. This appendix extends the investigation of 
sand movement by wind to smaller sand particle size ranges, and indicates 
that threshold velocity is best determined by experiment rather than by 
formula when the sand grain size is less than about 0.2 millimeters. 
Another report, "Beach Profile as Affected by Vertical Walls", was 
published as Beach Erosion Board Technical Memorandum No. 134. This report 
presents the results of a laboratory model study to investigate the equi- 
librium beach profile resulting when vertital walls of various top eleva- 
tions above or below the water surface elevation were located in the beach 
zone and subjected to wave action. As might be expected, walls of highest 
relative crest elevation, by allowing less energy to pass over the wall, 
resulted in greater scour in front of the wall; lower walls resulted in 
increased scour areas behind the wall. Effects of wave steepness and grain 
size of beach material were also investigated. As appreciable scale effect 
may be involved in such a study, care must be exercised in interpretation 
of the data for prototype use; nevertheless the data is considered of value 
in considering practical problems involving vertical face walls. 
A further report "Investigation on a Two-Phase Problem in Closed 
Pipes" was given limited distribution by the University of California as 
Institute of Engineering Research Technical Report HEL 2-2, This report 
concerns transportation of sediment in pipelines, and particularly dis- 
cusses two systems for measurement of concentration of the water-sediment 
mixture, and hence the transportation characteristics. Two measuring 
devices were tested, a loop-system consisting of two identical vertical 
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