6.5.2.3
Compaction by Other Methods—Compaction may
be accomplished by other approved methods, such as by
vibratory packer equipment, where care is taken to obtain a
uniform specimen without segregation of particle sizes (see
Test Methods
D 4253 and D 4254
).
6.5.3
Relative Density Intermediate Between 0 and
100 %—By trial in a separate container of the same diameter
as the permeability cylinder, adjust the compaction to obtain
reproducible values of relative density. Compact the soil in the
permeability cylinder by these procedures in thin layers to a
height about 2.0 cm (0.80 in.) above the upper manometer
outlet.
N
OTE
3—In order to bracket, systematically and representatively, the
relative density conditions that may govern in natural deposits or in
compacted embankments, a series of permeability tests should be made to
bracket the range of field relative densities.
6.6
Preparation of Specimen for Permeability Test:
6.6.1 Level the upper surface of the soil by placing the
upper porous plate or screen in position and by rotating it
gently back and forth.
6.6.2 Measure and record: the final height of specimen,
H
1
− H
2
, by measuring the depth,
H
2
, from the upper surface of
the perforated top plate employed to measure
H
1
to the top of
the upper porous plate or screen at four symmetrically spaced
points after compressing the spring lightly to seat the porous
plate or screen during the measurements; the final weight of
air-dried soil used in the test
(W
1
− W
2
) by weighing the
remainder of soil,
W
2
, left in the pan. Compute and record the
unit weights, void ratio, and relative density of the test
specimen.
6.6.3 With its gasket in place, press down the top plate
against the spring and attach it securely to the top of the
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