392
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Problems related to the double hydrometer tests pose the
potential for misleading results since the test is associated with a
number of different parameters in the rating systems. Inaccurate
results from the double hydrometer test can significantly affect
the correlation of the final rating, particularly when this test
method is used as the reference methods for the preliminary
classification of the dispersivity of soils (Gerber and Harmse,
1987; Bell and Maud, 1994; Walker, 1997).
It is therefore necessary to stress the importance of
developing and following a standard protocol for the test. In
order to reduce the variation/inconsistencies in results, it is
essential that the test method is reviewed and the optimum
procedure developed. The procedure should be simple and have
as few ambiguities as possible so that no misinterpretations can
occur.
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