Standard Test Method for Particle-Size Analysis of Soils

ABSTRACT
This test method covers the quantitative determination of the distribution of particle sizes in soils. The distribution of particle sizes larger than 75 micrometers (retained on the No. 200 sieve) is determined by sieving, while the distribution of particle sizes smaller than 75 micrometers is determined by a sedimentation process using a hydrometer. The balances, stirring apparatus, hydrometer, sedimentation cylinder, thermometer, sieves, water bath or constant-temperature room, beaker, and timing device used in the method are specified. Sieve analysis, hydrometer analysis, and hygroscopic moisture analysis shall be performed on the sample soil.
SCOPE
1.1 This test method covers the quantitative determination of the distribution of particle sizes in soils. The distribution of particle sizes larger than 75 μm (retained on the No. 200 sieve) is determined by sieving, while the distribution of particle sizes smaller than 75 μm is determined by a sedimentation process, using a hydrometer to secure the necessary data (Note 1 and Note 2). Note 1
Separation may be made on the No. 4 (4.75 μm), No. 40 (425 μm), or No. 200 (75 μm) sieve instead of the No. 10. For whatever sieve used, the size shall be indicated in the report.Note 2
Two types of dispersion devices are provided: (1) a high-speed mechanical stirrer, and (2) air dispersion. Extensive investigations indicate that air-dispersion devices produce a more positive dispersion of plastic soils below the 20-m size and appreciably less degradation on all sizes when used with sandy soils. Because of the definite advantages favoring air dispersion, its use is recommended. The results from the two types of devices differ in magnitude, depending upon soil type, leading to marked differences in particle size distribution, especially for sizes finer than 20 m.

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D422 − 63(Reapproved 2007)
Standard Test Method for
Particle-Size Analysis of Soils
This standard is issued under the fixed designation D422; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 3. Apparatus
3.1 Balances—A balance sensitive to 0.01 g for weighing
1.1 This test method covers the quantitative determination
of the distribution of particle sizes in soils. The distribution of the material passing a No. 10 (2.00-mm) sieve, and a balance
sensitive to 0.1 % of the mass of the sample to be weighed for
particle sizes larger than 75 µm (retained on the No. 200 sieve)
isdeterminedbysieving,whilethedistributionofparticlesizes weighing the material retained on a No. 10 sieve.
smaller than 75 µm is determined by a sedimentation process,
3.2 Stirring Apparatus—Either apparatus A or B may be
using a hydrometer to secure the necessary data (Note 1 and
used.
Note 2).
3.2.1 Apparatus A shall consist of a mechanically operated
stirringdeviceinwhichasuitablymountedelectricmotorturns
NOTE 1—Separation may be made on the No. 4 (4.75-mm), No. 40
(425-µm), or No. 200 (75-µm) sieve instead of the No. 10. For whatever a vertical shaft at a speed of not less than 10 000 rpm without
sieve used, the size shall be indicated in the report.
load. The shaft shall be equipped with a replaceable stirring
NOTE 2—Two types of dispersion devices are provided: (1) a high-
paddle made of metal, plastic, or hard rubber, as shown in Fig.
speed mechanical stirrer, and (2) air dispersion. Extensive investigations
1. The shaft shall be of such length that the stirring paddle will
indicate that air-dispersion devices produce a more positive dispersion of
3 1
operate not less than ⁄4 in. (19.0 mm) nor more than 1 ⁄2 in.
plastic soils below the 20-µm size and appreciably less degradation on all
sizes when used with sandy soils. Because of the definite advantages (38.1 mm) above the bottom of the dispersion cup. A special
favoring air dispersion, its use is recommended. The results from the two
dispersion cup conforming to either of the designs shown in
types of devices differ in magnitude, depending upon soil type, leading to
Fig. 2 shall be provided to hold the sample while it is being
marked differences in particle size distribution, especially for sizes finer
dispersed.
than 20 µm.
3.2.2 Apparatus B shall consist of an air-jet dispersion cup
(See drawing)(Note 3) conforming to the general details
2. Referenced Documents
shown in Fig. 3 (Note 4 and Note 5).
2.1 ASTM Standards:
NOTE 3—The amount of air required by an air-jet dispersion cup is of
D421 Practice for Dry Preparation of Soil Samples for
the order of 2 ft /min; some small air compressors are not capable of
Particle-Size Analysis and Determination of Soil Con-
supplying sufficient air to operate a cup.
stants
NOTE 4—Another air-type dispersion device, known as a dispersion
E11 Specification for Woven Wire Test Sieve Cloth and Test
tube, developed by Chu and Davidson at Iowa State College, has been
shown to give results equivalent to those secured by the air-jet dispersion
Sieves
cups. When it is used, soaking of the sample can be done in the
E100 Specification for ASTM Hydrometers
sedimentation cylinder, thus eliminating the need for transferring the
2.2 ASTM Adjuncts:
slurry. When the air-dispersion tube is used, it shall be so indicated in the
report.
Air-Jet Dispersion Cup for Grain-Size Analysis of Soil
NOTE 5—Water may condense in air lines when not in use. This water
must be removed, either by using a water trap on the air line, or by
blowing the water out of the line before using any of the air for dispersion
purposes.
This test method is under the jurisdiction ofASTM Committee D18 on Soil and
Rock and is the direct responsibility of Subcommittee D18.03 on Texture, Plasticity
3.3 Hydrometer—An ASTM hydrometer, graduated to read
and Density Characteristics of Soils.
in either specific gravity of the suspension or grams per litre of
Current edition approved Oct. 15, 2007. Published October 2007. Originally
ε1
approved in 1935. Last previous edition approved in 2002 as D422 – 63 (2002) .
suspension, and conforming to the requirements for hydrom-
DOI: 10.1520/D0422-63R07.
eters 151H or 152H in Specifications E100. Dimensions of
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
both hydrometers are the same, the scale being the only item of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
difference.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3.4 SedimentationCylinder—Aglass cylinder essentially 18
Available from ASTM International Headquarters. Order Adjunct No.
ADJD0422. in. (457 mm) in height and 2 ⁄2 in. (63.5 mm) in diameter, and
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D422 − 63 (2007)
Metric Equivalents
1 3
in. 0.001 0.049 0.203 ⁄2 ⁄4
mm 0.03 1.24 5.16 12.7 19.0
FIG. 1 Detail of Stirring Paddles
NOTE 6—Aset of sieves giving uniform spacing of points for the graph,
as required in Section 17, may be used if desired. This set consists of the
following sieves:
3-in. (75-mm) No. 16 (1.18-mm)
1 ⁄2-in. (37.5-mm) No. 30 (600-µm)
⁄4-in. (19.0-mm) No. 50 (300-µm)
⁄8-in. (9.5-mm) No. 100 (150-µm)
No. 4 (4.75-mm) No. 200 (75-µm)
No. 8 (2.36-mm)
3.7 Water Bath or Constant-Temperature Room—A water
bath or constant-temperature room for maintaining the soil
suspension at a constant temperature during the hydrometer
analysis. A satisfactory water tank is an insulated tank that
maintains the temperature of the suspension at a convenient
constant temperature at or near 68°F (20°C). Such a device is
illustrated in Fig. 4. In cases where the work is performed in a
room at an automatically controlled constant temperature, the
water bath is not necessary.
3.8 Beaker—A beaker of 250-mL capacity.
3.9 Timing Device—A watch or clock with a second hand.
Metric Equivalents
4. Dispersing Agent
in. 1.3 2.6 3.75
4.1 A solution of sodium hexametaphosphate (sometimes
mm 33 66 95.2
called sodium metaphosphate) shall be used in distilled or
FIG. 2 Dispersion Cups of Apparatus
demineralized water, at the rate of 40 g of sodium
hexametaphosphate/litre of solution (Note 7).
marked for a volume of 1000 mL. The inside diameter shall be
such that the 1000-mL mark is 36 6 2 cm from the bottom on NOTE 7—Solutions of this salt, if acidic, slowly revert or hydrolyze
back to the orthophosphate form with a resultant decrease in dispersive
the inside.
action. Solutions should be prepared frequently (at least once a month) or
3.5 Thermometer—A thermometer accurate to 1°F (0.5°C).
adjusted to pH of 8 or 9 by means of sodium carbonate. Bottles containing
solutions should have the date of preparation marked on them.
3.6 Sieves—A series of sieves, of square-mesh woven-wire
4.2 All water used shall be either distilled or demineralized
cloth, conforming to the requirements of Specification E11.A
water. The water for a hydrometer test shall be brought to the
full set of sieves includes the following (Note 6):
temperature that is expected to prevail during the hydrometer
3-in. (75-mm) No. 10 (2.00-mm)
2-in. (50-mm) No. 20 (850-µm) test. For example, if the sedimentation cylinder is to be placed
1 ⁄2-in. (37.5-mm) No. 40 (425-µm)
in the water bath, the distilled or demineralized water to be
1-in. (25.0-mm) No. 60 (250-µm)
usedshallbebroughttothetemperatureofthecontrolledwater
⁄4-in. (19.0-mm) No. 140 (106-µm)
⁄8-in. (9.5-mm) No. 200 (75-µm) bath; or, if the sedimentation cylinder is used in a room with
No. 4 (4.75-mm)
controlled temperature, the water for the test shall be at the
D422 − 63 (2007)
FIG. 3 Air-Jet Dispersion Cups of Apparatus B
Metric Equivalents
7 1
in. ⁄8 13 6 ⁄4 14 37
mm 22.2 25.4 76.2 158.2 356 940
FIG. 4 Insulated Water Bath
temperature of the room. The basic temperature for the
Nominal Diameter of Approximate Minimum
Largest Particles, Mass of Portion, g
hydrometer test is 68°F (20°C). Small variations of tempera-
in. (mm)
ture do not introduce differences that are of practical signifi-
⁄8 (9.5) 500
cance and do not prevent the use of corrections derived as
⁄4 (19.0) 1000
1 (25.4) 2000
prescribed.
1 ⁄2 (38.1) 3000
2 (50.8) 4000
5. Test Sample
3 (76.2) 5000
5.1 Prepare the test sample for mechanical analysis as
5.1.2 The size of the portion passing the No. 10 sieve shall
outlined in Practice D421. During the preparation procedure
be approximately 115 g for sandy soils and approximately 65
the sample is divided into two portions. One portion contains
g for silt and clay soils.
onlyparticlesretainedontheNo.10(2.00-mm)sievewhilethe
5.2 Provision is made in Section 5 of Practice D421 for
other portion contains only particles passing the No. 10 sieve.
weighing of the air-dry soil selected for purpose of tests, the
The mass of air-dried soil selected for purpose of tests, as
separation of the soil on the No. 10 sieve by dry-sieving and
prescribed in Practice D421, shall be sufficient to yield
washing, and the weighing of the washed and dried fraction
quantities for mechanical analysis as follows:
5.1.1 The size of the portion retained on the No. 10 sieve retained on the No. 10 sieve. From these two masses the
percentages retained and passing the No. 10 sieve can be
shall depend on the maximum size of particle, according to the
following schedule: calculated in accordance with 12.1.
D422 − 63 (2007)
NOTE 8—A check on the mass values and the thoroughness of
temperatures,andcorrectionsfortheintermediatetemperatures
pulverization of the clods may be secured by weighing the portion passing
calculated assuming a straight-line relationship between the
the No. 10 sieve and adding this value to the mass of the washed and
two observed values.
oven-dried portion retained on the No. 10 sieve.
7.3 Prepare 1000 mL of liquid composed of distilled or
SIEVE ANALYSIS OF PORTION RETAINED ON NO.
demineralized water and dispersing agent in the same propor-
tion as will prevail in the sedimentation (hydrometer) test.
(2.00-mm) SIEVE
Place the liquid in a sedimentation cylinder and the cylinder in
the constant-temperature water bath, set for one of the two
6. Procedure
temperatures to be used. When the temperature of the liquid
6.1 Separate the portion retained on the No. 10 (2.00-mm)
becomes constant, insert the hydrometer, and, after a short
sieve into a series of fractions using the 3-in. (75-mm), 2-in.
interval to permit the hydrometer to come to the temperature of
1 3
(50-mm), 1 ⁄2-in. (37.5-mm), 1-in. (25.0-mm), ⁄4-in. (19.0-
the liquid, read the hydrometer at the top of the meniscus
mm), ⁄8-in. (9.5-mm), No. 4 (4.75-mm), and No. 10 sieves, or
formed on the stem. For hydrometer 151H the composite
as many as may be needed depending on the sample, or upon
correction is the difference between this reading and one; for
the specifications for the material under test.
hydrometer 152H it is the difference between the reading and
zero. Bring the liquid and the hydrometer to the other tempera-
6.2 Conduct the sieving operation by means of a lateral and
ture to be used, and secure the composite correction as before.
vertical motion of the sieve, accompanied by a jarring action in
order to keep the sample moving continuously over the surface
8. Hygroscopic Moisture
of the sieve. In no case turn or manipulate fragments in the
sample through the sieve by hand. Continue sieving until not
8.1 When the sample is weighed for the hydrometer test,
more than 1 mass % of the residue on a sieve passes that sieve
weigh out an auxiliary portion of from 10 to 15 g in a small
during 1 min of sieving. When mechanical sieving is used, test
metal or glass container, dry the sample to a constant mass in
the thoroughness of sieving by using the hand method of
an oven at 230 6 9°F (110 6 5°C), and weigh again. Record
sieving as described above.
the masses.
6.3 Determine the mass of each fraction on a balance
9. Dispersion of Soil Sample
conforming to the requirements of 3.1.At the end of weighing,
the sum of the masses retained on all the sieves used should
9.1 When the soil is mostly of the clay and silt sizes, weigh
equal closely the original mass of the quantity sieved.
out a sample of air-dry soil of approximately 50 g. When the
soil is mostly sand the sample should be approximately 100 g.
HYDROMETER AND SIEVE ANALYSIS OF PORTION
9.2 Place the sample in the 250-mL beaker and cover with
PASSING THE NO. 10 (2.00-mm) SIEVE
125 mL of sodium hexametaphosphate solution (40 g/L). Stir
7. Determination of Composite Correction for
until the soil is thoroughly wetted.Allow to soak for at least 16
Hydrometer Reading
h.
7.1 Equations for percentages of soil remaining in
9.3 At the end of the soaking period, disperse the sample
suspension, as given in 14.3, are based on the use of distilled
further, using either stirring apparatus A or B. If stirring
or demineralized water.Adispersing agent is used in the water,
apparatus A is used, transfer the soil-water slurry from the
however, and the specific gravity of the resulting liquid is
beaker into the special dispersion cup shown in Fig. 2, washing
appreciably greater than that of distilled or demineralized
any residue from the beaker into the cup with distilled or
water.
demineralized water (Note 9). Add distilled or demineralized
7.1.1 Both soil hydrometers are calibrated at 68°F (20°C),
water, if necessary, so that the cup is more than half full. Stir
and variations in temperature from this standard temperature
for a period of 1 min.
produce inaccuracies in the actual hydrometer readings. The
NOTE 9—A large size syringe is a convenient device for handling the
amount of the inaccuracy increases as the variation from the
water in the washing operation. Other devices include the wash-water
standard temperature increases.
bottle and a hose with nozzle connected to a pressurized distilled water
7.1.2 Hydrometers are graduated by the manufacturer to be tank.
read at the bottom of the meniscus formed by the liquid on the
9.4 If stirring apparatus B (Fig. 3) is used, remove the cover
stem. Since it is not possible to secure readings of soil
cap and connect the cup to a compressed air supply by means
suspensions at the bottom of the meniscus, readin
...


This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation:D422–63 (Reapproved 2002) Designation: D 422 – 63 (Reapproved 2007)
Standard Test Method for
Particle-Size Analysis of Soils
This standard is issued under the fixed designation D 422; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
´ NOTE—Adjunct references were corrected editorially in July 2006.
1. Scope
1.1 This test method covers the quantitative determination of the distribution of particle sizes in soils. The distribution of
particle sizes larger than 75 µm (retained on the No. 200 sieve) is determined by sieving, while the distribution of particle sizes
smaller than 75 µm is determined by a sedimentation process, using a hydrometer to secure the necessary data (Note 1 and Note
2).
NOTE 1—Separation may be made on the No. 4 (4.75-mm), No. 40 (425-µm), or No. 200 (75-µm) sieve instead of the No. 10. For whatever sieve used,
the size shall be indicated in the report.
NOTE 2—Two types of dispersion devices are provided: (1) a high-speed mechanical stirrer, and (2) air dispersion. Extensive investigations indicate
that air-dispersion devices produce a more positive dispersion of plastic soils below the 20-µm size and appreciably less degradation on all sizes when
used with sandy soils. Because of the definite advantages favoring air dispersion, its use is recommended.The results from the two types of devices differ
in magnitude, depending upon soil type, leading to marked differences in particle size distribution, especially for sizes finer than 20 µm.
2. Referenced Documents
2.1 ASTM Standards:
D 421 Practice for Dry Preparation of Soil Samples for Particle-Size Analysis and Determination of Soil Constants
E11 Specification for Wire-Cloth Sieves for Testing Purposes Specification for Wire Cloth and Sieves for Testing Purposes
E 100 Specification for ASTM Hydrometers
2.2 ASTM Adjuncts:
Air-Jet Dispersion Cup for Grain-Size Analysis of Soil
3. Apparatus
3.1 Balances—Abalancesensitiveto0.01gforweighingthematerialpassingaNo.10(2.00-mm)sieve,andabalancesensitive
to 0.1 % of the mass of the sample to be weighed for weighing the material retained on a No. 10 sieve.
3.2 Stirring Apparatus—Either apparatus A or B may be used.
3.2.1 Apparatus A shall consist of a mechanically operated stirring device in which a suitably mounted electric motor turns a
vertical shaft at a speed of not less than 10 000 rpm without load. The shaft shall be equipped with a replaceable stirring paddle
made of metal, plastic, or hard rubber, as shown in Fig. 1. The shaft shall be of such length that the stirring paddle will operate
3 1
not less than ⁄4 in. (19.0 mm) nor more than 1 ⁄2 in. (38.1 mm) above the bottom of the dispersion cup. A special dispersion cup
conforming to either of the designs shown in Fig. 2 shall be provided to hold the sample while it is being dispersed.
3.2.2 Apparatus B shall consist of an air-jet dispersion cup (SeeADJD0422drawing ) (Note 3) conforming to the general details
shown in Fig. 3 (Note 4 and Note 5).
NOTE 3—The amount of air required by an air-jet dispersion cup is of the order of 2 ft /min; some small air compressors are not capable of supplying
sufficient air to operate a cup.
NOTE 4—Another air-type dispersion device, known as a dispersion tube, developed by Chu and Davidson at Iowa State College, has been shown to
give results equivalent to those secured by the air-jet dispersion cups. When it is used, soaking of the sample can be done in the sedimentation cylinder,
thus eliminating the need for transferring the slurry. When the air-dispersion tube is used, it shall be so indicated in the report.
This test method is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.03 on Texture, Plasticity
and Density Characteristics of Soils.
Current edition approved July 27, 2006. Published March 2003Originally published in 1935. Last previous edition approved in 1998 as D422–63 (1998).
´1
Current edition approved Oct. 15, 2007. Published October 2007. Originally approved in 1935. Last previous edition approved in 2002 as D 422 – 63 (2002) .
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. ForAnnualBookofASTMStandards
, Vol 04.08.volume information, refer to the standard’s Document Summary page on the ASTM website.
Annual Book of ASTM Standards, Vol 14.02.
Available from ASTM International Headquarters. Order Adjunct No. ADJD0422.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 422 – 63 (2007)
Metric Equivalents
1 3
in. 0.001 0.049 0.203 ⁄2 ⁄4
mm 0.03 1.24 5.16 12.7 19.0
FIG. 1 Detail of Stirring Paddles
Metric Equivalents
in. 1.3 2.6 3.75
mm 33 66 95.2
FIG. 2 Dispersion Cups of Apparatus
NOTE 5—Water may condense in air lines when not in use. This water must be removed, either by using a water trap on the air line, or by blowing
the water out of the line before using any of the air for dispersion purposes.
3.3 Hydrometer—An ASTM hydrometer, graduated to read in either specific gravity of the suspension or grams per litre of
suspension, and conforming to the requirements for hydrometers 151H or 152H in Specifications E 100. Dimensions of both
hydrometers are the same, the scale being the only item of difference.
3.4 Sedimentation Cylinder—A glass cylinder essentially 18 in. (457 mm) in height and 2 ⁄2 in. (63.5 mm) in diameter, and
marked for a volume of 1000 mL. The inside diameter shall be such that the 1000-mL mark is 36 6 2 cm from the bottom on the
inside.
3.5 Thermometer—A thermometer accurate to 1°F (0.5°C).
3.6 Sieves—Aseries of sieves, of square-mesh woven-wire cloth, conforming to the requirements of Specification E 11.Afull
set of sieves includes the following (Note 6):
D 422 – 63 (2007)
FIG. 3 Air-Jet Dispersion Cups of Apparatus B
3-in. (75-mm) No. 10 (2.00-mm)
2-in. (50-mm) No. 20 (850-µm)
1 ⁄2-in. (37.5-mm) No. 40 (425-µm)
1-in. (25.0-mm) No. 60 (250-µm)
⁄4-in. (19.0-mm) No. 140 (106-µm)
⁄8-in. (9.5-mm) No. 200 (75-µm)
No. 4 (4.75-mm)
NOTE 6—A set of sieves giving uniform spacing of points for the graph, as required in Section 17, may be used if desired. This set consists of the
following sieves:
3-in. (75-mm) No. 16 (1.18-mm)
1 ⁄2-in. (37.5-mm) No. 30 (600-µm)
⁄4-in. (19.0-mm) No. 50 (300-µm)
⁄8-in. (9.5-mm) No. 100 (150-µm)
No. 4 (4.75-mm) No. 200 (75-µm)
No. 8 (2.36-mm)
3.7 Water Bath or Constant-Temperature Room—A water bath or constant-temperature room for maintaining the soil
suspension at a constant temperature during the hydrometer analysis.Asatisfactory water tank is an insulated tank that maintains
the temperature of the suspension at a convenient constant temperature at or near 68°F (20°C). Such a device is illustrated in Fig.
4. In cases where the work is performed in a room at an automatically controlled constant temperature, the water bath is not
necessary.
3.8 Beaker—A beaker of 250-mL capacity.
Metric Equivalents
7 1
in. ⁄8 13 6 ⁄4 14 37
mm 22.2 25.4 76.2 158.2 356 940
FIG. 4 Insulated Water Bath
D 422 – 63 (2007)
3.9 Timing Device—A watch or clock with a second hand.
4. Dispersing Agent
4.1 A solution of sodium hexametaphosphate (sometimes called sodium metaphosphate) shall be used in distilled or
demineralized water, at the rate of 40 g of sodium hexametaphosphate/litre of solution (Note 7).
NOTE 7—Solutions of this salt, if acidic, slowly revert or hydrolyze back to the orthophosphate form with a resultant decrease in dispersive action.
Solutions should be prepared frequently (at least once a month) or adjusted to pH of 8 or 9 by means of sodium carbonate. Bottles containing solutions
should have the date of preparation marked on them.
4.2 All water used shall be either distilled or demineralized water. The water for a hydrometer test shall be brought to the
temperature that is expected to prevail during the hydrometer test. For example, if the sedimentation cylinder is to be placed in
the water bath, the distilled or demineralized water to be used shall be brought to the temperature of the controlled water bath; or,
if the sedimentation cylinder is used in a room with controlled temperature, the water for the test shall be at the temperature of
the room. The basic temperature for the hydrometer test is 68°F (20°C). Small variations of temperature do not introduce
differences that are of practical significance and do not prevent the use of corrections derived as prescribed.
5. Test Sample
5.1 Prepare the test sample for mechanical analysis as outlined in Practice D 421. During the preparation procedure the sample
is divided into two portions. One portion contains only particles retained on the No. 10 (2.00-mm) sieve while the other portion
contains only particles passing the No. 10 sieve. The mass of air-dried soil selected for purpose of tests, as prescribed in Practice
D 421, shall be sufficient to yield quantities for mechanical analysis as follows:
5.1.1 The size of the portion retained on the No. 10 sieve shall depend on the maximum size of particle, according to the
following schedule:
Nominal Diameter of Approximate Minimum
Largest Particles, Mass of Portion, g
in. (mm)
⁄8 (9.5) 500
⁄4 (19.0) 1000
1 (25.4) 2000
1 ⁄2 (38.1) 3000
2 (50.8) 4000
3 (76.2) 5000
5.1.2 The size of the portion passing the No. 10 sieve shall be approximately 115 g for sandy soils and approximately 65 g for
silt and clay soils.
5.2 Provision is made in Section 5 of Practice D 421 for weighing of the air-dry soil selected for purpose of tests, the separation
of the soil on the No. 10 sieve by dry-sieving and washing, and the weighing of the washed and dried fraction retained on the No.
10 sieve. From these two masses the percentages retained and passing the No. 10 sieve can be calculated in accordance with 12.1.
NOTE 8—A check on the mass values and the thoroughness of pulverization of the clods may be secured by weighing the portion passing the No. 10
sieve and adding this value to the mass of the washed and oven-dried portion retained on the No. 10 sieve.
SIEVE ANALYSIS OF PORTION RETAINED ON NO. 10
(2.00-mm) SIEVE
6. Procedure
6.1 Separate the portion retained on the No. 10 (2.00-mm) sieve into a series of fractions using the 3-in. (75-mm), 2-in.
1 3 3
(50-mm), 1 ⁄2-in. (37.5-mm), 1-in. (25.0-mm), ⁄4-in. (19.0-mm), ⁄8-in. (9.5-mm), No. 4 (4.75-mm), and No. 10 sieves, or as many
as may be needed depending on the sample, or upon the specifications for the material under test.
6.2 Conduct the sieving operation by means of a lateral and vertical motion of the sieve, accompanied by a jarring action in
order to keep the sample moving continuously over the surface of the sieve. In no case turn or manipulate fragments in the sample
through the sieve by hand. Continue sieving until not more than 1 mass % of the residue on a sieve passes that sieve during 1 min
of sieving. When mechanical sieving is used, test the thoroughness of sieving by using the hand method of sieving as described
above.
6.3 Determine the mass of each fraction on a balance conforming to the requirements of 3.1. At the end of weighing, the sum
of the masses retained on all the sieves used should equal closely the original mass of the quantity sieved.
HYDROMETER AND SIEVE ANALYSIS OF PORTION PASSING THE NO. 10 (2.00-mm) SIEVE
7. Determination of Composite Correction for Hydrometer Reading
7.1 Equationsforpercentagesofsoilremaininginsuspension,asgivenin14.3,arebasedontheuseofdistilledordemineralized
water.Adispersing agent is used in the water, however, and the specific gravity of the resulting liquid is appreciably greater than
that of distilled or demineralized water.
D 422 – 63 (2007)
7.1.1 Both soil hydrometers are calibrated at 68°F (20°C), and variations in temperature from this standard temperature produce
inaccuracies in the actual hydrometer readings. The amount of the inaccuracy increases as the variation from the standard
temperature increases.
7.1.2 Hydrometers are graduated by the manufacturer to be read at the bottom of the meniscus formed by the liquid on the stem.
Since it is not possible to secure readings of soil suspensions at the bottom of the meniscus, readings must be taken at the top and
a correction applied.
7.1.3 The net amount of the corrections for the three items enumerated is designated as the composite correction, and may be
determined experimentally.
7.2 For convenience, a graph or table of composite corrections for a series of 1° temperature differences for the range of
expected test temperatures may be prepared and used as needed. Measurement of the composite corrections may be made at two
temperatures spanning the range of expected test temperatures, and corrections for the intermediate temperatures calculated
assuming a straight-line relationship between the two observed values.
7.3 Prepare 1000 mLof liquid composed of distilled or demineralized water and dispersing agent in the same proportion as will
prevail in the sedimentation (hydrometer) test. Place the liquid in a sedimentation cylinder and the cylinder in the
constant-temperature water bath, set for one of the two temperatures to be used. When the temperature of the liquid becomes
constant, insert the hydrometer, and, after a short interval to permit the hydrometer to come to the temperature of the liquid, read
the hydrometer at the top of the meniscus formed on the stem. For hydrometer 151H the composite correction is the difference
between this reading and one; for hydrometer 152H it is the difference between the reading and zero. Bring the liquid and the
hydrometer to the other temperature to be used, and secure the composite correction as before.
8. Hygroscopic Moisture
8.1 When the sample is weighed for the hydrometer test, weigh out an auxiliary portion of from 10 to 15 g in a small metal
or glass container, dry the sample to a constant mass in an oven at 230 6 9°F (110 6 5°C), and weigh again. Rec
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