In hydrometer analysis for soil grain size distribution,
usually, the grains passing sieve No. 200 (<0.074 mm)
are used. However, the hydrometer results occasionally give diameters greater
than 0.074 mm. This event causes a mismatch in the curve of grain size
distribution obtained from sieving and hydrometer methods. Hence, a new
approach is proposed for smoothing soil grain size curve determined by
hydrometer using Excel-2007 with simple statistical methods. The treatments
show that in case of large sizes, there are big differences between the values
of soil grain diameters smoothed by Excel-2007 in comparison and the
values measured by references. These differences generally decrease with
decreasing soil grain size diameters. The statistical treatments also divulge whether the hydrometer results are accurate or not. Furthermore, a general equation
has been derived to estimate values of K factor, which is used
for calculating the grain diameters in hydrometer analysis. The equation can be
applied for any specific gravity of soils and for wide range temperatures.
Cite this paper
M. AL-Jumaily and T. AL-Dabbagh, "A New Approach for Smoothing Soil Grain Size Curve Determined by Hydrometer," International Journal of Geosciences
, Vol. 4 No. 9, 2013, pp. 1285-1291. doi: 10.4236/ijg.2013.49123
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