Theoretical Investigations . An analytical study has been initiated 

 on friction loss of waves. A iiBthod is developed which will give a more 

 direct solution for the fi-iction wave height as conpaL-ed to the solution 

 by successive appro idinations as given by Putnam and JolTnson, 



The data obtained during the field trip last suini'ier xclII be used to 

 deterirdne the jTriction factors associated x-jith the bottom materials and 

 wave characteristics. The bottom materials at the Atchafala^-a Bay Region 

 consist of a gelatinous inud, particle size range between ,001 mrii aiid 

 .OOL. mm, with a/parfecle diameter of .002 mm. No percolation loss is 

 ejqjected of the wave data obtained last suLiiiBr, and consequently percola-^ 

 tion need not be considered, A report on tliis study will be conpleted by 

 March 1, 19^3. 



V. Waterwa;rs E:cperiment Station^ Vicksburg, I'iississippi, Quarterly Beport 

 for ^^grter ending 31 "December 1952. 



>Jave Ruji-up on Shore Structures . The purpose of this stixdy is to in- 

 vestigate the relationship between water level, wave height, wave p-^riod 

 snd beach slope and wave run-up on selected types of shore structures 

 used to prevent erosion caused by wave action. 



Tests are being conducted using a scale of 1:17 in a wave flume 120 

 feet long, 5 i'eet wide and 5 feet deep. -laves are generated by a plunger- 

 t-^rpe wave machine,- VJave heights are neasured by a parallel-rod- tj^pe wave 

 gage. Selected structures are placed on m.olded beaches, and the height 

 of wave run-up (for no overtopping) and the amount of water overtopping 

 the structure are determined. 



Tests to determine the volumes of over'-^opping water for vertical-faced, 

 monolithic seax^^alls x-fith crox-m elevations of +6.0, +0,9, +12,0 and +1^,0 

 ft. swl, using a beach slope of 1 on 10 and water depths of 25,0, 29.5 and 

 3li,0 ft,, x-jere couple ted during the quarter, 



VI, Beach Erosion Board, Research Division, Project Status Report for 

 Qaarter Ending 31 I'larch 1953 « 



In addition to the research projects under contract to the various 

 institutions xvhich are reported on above, the Research Division of the 

 Beach Erosion Board is carrying out certai-n projects xclth its oxm facilities. 

 The main projects were described in 7ol, 6, No, k of the Bulletin (October 

 1952) and a short description of the x^ork accomplished through the last 

 quarter is given beloxf. 



Study of Effects of Tidal Fluctuations on Wave Prodyiced Beach Profile s - 

 Testing x-xas resui,-Bd in February 3n.d the testing for tte U-hour tidal cycle 

 co5Tpleted, Further testing has had to be discontinued for the present 

 due to the priority of other xfork. 



Ih 



