The Effects of Wind and Salinity Upon the Sedimentation Rates of Soils From Dredging Sites in Alabemarle Sound, North Carolina

Clay, loam, silt, and sand soil samples collected from dredging sites in Albemarle Sound were suspended in solutions of sea water varying from 0 to 25 per cent sea strength. Sedimentation rates were obtained by measuring the amount of light transmission through each solution as described by Coggin, 1960. Test suspensions were placed in a wind tunnel to determine the effect of wind action on sedimentation rates. Except for sand, no appreciable sedimentation of the suspended soils occurred in the zero concentrations of sea water during the entire test period. Rapid sedimentation of the other soil types tested occurred during the first 8 hours in all tests of all sea-water concentrations and no appreciable difference was noted between the various percentages of sea water. A simulated wind velocity of 7 miles per hour had no appreciable effect on the sedimentation rates in 10 per cent sea water. A wind velocity of 14 miles per hour precluded any appreciable sedimentation of soils in the sea-water concentrations tested. The agitational effects of wind action on the material suspended in the solutions was greater than the accelerated rate of sedimentation provided by the sea-water concentrations tested.

MCCOY-358.pdf374.99 KB
Starting page
Ending page