PROGRESS REPORTS ON RESEARCH SPONSORED BY 

 THE BEACH EROSION BOARD 



Abstracts from progresvs reports on several research contracts in 

 force between universities or other institutions and the Beach Erosion 

 Board, together with brief statements as to the status of research 

 projects being prosecuted in the laboratory of the Beach Erosion Board 

 are presented as follows: 



I. University of California, Contract No. Dk-k9 -00% -eng-8 , Status 

 Report No. 16, 1 July through 30 September 195U . 



Good progress was made on the statistical compilation of the data 

 for the sand samples collected around the rocky promontories in Southern 

 California. This compilation is now 90 percent completed. 



In September a voyage was made in cooperation with Scripps Institution 

 of Oceanography using the vessel E. R. SCRIPPS, to take underwater photo- 

 graphs of the sediments off Point Dume, and the southern side of Catalina 

 Island. A good selection of photographs was obtained by aqualung divers, 

 the divers being trained scientists who made detailed observations of the 

 sea bottom in conjunction with the photographs. A well defined series 

 of ripple marks were present upon the sea bottom in this area, their 

 axes being essentially parallel to the front of the waves approaching 

 the coast. In one place transverse sand waves with amplitudes of 6 to 7 

 feet and heights of nearly 1 foot were observed just outside the breaker 

 zone. The axis of these ripples was essentially at right angles to the 

 coast line. 



II. University of California , Contract No. DA-lj9-OOg-eng-17, Status 

 Reports h,5 and 6, 1 January to 30 September 195U . 



Experimental work on the various stages of ripple formations until 

 their final disappearance was continued using materials of different 

 sizes and density. Analyses indicate that steepness of the ripples during 

 these stages can be described as a function of a diraensionless parameter 

 involving the maximum velocity, density, and size of the particles, and 

 the kinematic viscosity of the fluid in which the motion takes place. The 

 function can also be used to define the initial and general movements and 

 also the initiation and the final disappearance of the ripples. 



III. University of California, Contract No. DA-k9-005-eng-31, Status 

 Report No. 5 (Final) 1 August - 1 October 19& . 



Three reports dealing with water surface roughness and shear stress, 

 and wind waves and set-up in shallow water were in preparation. 



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