ASTM D7370/D7370M-14(2021)
(Test Method)Standard Test Method for Determination of Relative Density and Absorption of Fine, Coarse, and Blended Aggregate Using Combined Vacuum Saturation and Rapid Submersion
Standard Test Method for Determination of Relative Density and Absorption of Fine, Coarse, and Blended Aggregate Using Combined Vacuum Saturation and Rapid Submersion
SIGNIFICANCE AND USE
4.1 Relative density (specific gravity) is the characteristic generally used for calculation of the volume occupied by the aggregate in various mixtures containing aggregate, including portland cement concrete, bituminous concrete, and other mixtures that are proportioned or analyzed on an absolute volume basis. Relative density (specific gravity) is also used in the computation of voids in aggregate in Test Method C29/C29M. Relative density (specific gravity) saturated surface dry (SSD) is used if the aggregate is at SSD, that is, if its absorption has been satisfied. Conversely, the relative density (specific gravity) oven dry (OD) is used for computations when the aggregate is dry or assumed to be dry.
4.2 Apparent density and apparent relative density (apparent specific gravity) pertain to the solid material making up the constituent particles not including the pore space within the particles which is accessible to water.
4.3 Absorption values are used to calculate the change in the mass of an aggregate due to water absorbed in the pore spaces within the constituent particles, when it is deemed that the aggregate has been in contact with water long enough to satisfy the absorption potential. The laboratory standard for absorption is that obtained after submerging dry aggregate for a prescribed period of time.
Note 1: There are other test methods that have been used and continue to be used to determine these aggregate properties: Test Methods C127 and C128. This test method may result in values for these properties that are close to or divergent from values from other test methods.
Note 2: The quality of the results produced by this standard are dependent upon the competence of the personnel performing the procedure and the capability, calibration, and the maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this ...
SCOPE
1.1 This test method covers the determination of relative density and absorption of fine aggregates by Method A and coarse and blended aggregates by Method B.
1.2 A multi-laboratory precision and bias statement for coarse and combined aggregate tests in this standard has not been developed at this time. Therefore, this standard should not be used for acceptance or rejection of coarse and combined aggregate materials for purchasing purposes.
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Some values have only SI units because inch-pound equivalents are not used in practice.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
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Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7370/D7370M − 14 (Reapproved 2021)
Standard Test Method for
Determination of Relative Density and Absorption of Fine,
Coarse, and Blended Aggregate Using Combined Vacuum
Saturation and Rapid Submersion
This standard is issued under the fixed designation D7370/D7370M; 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.
1. Scope C29/C29M Test Method for Bulk Density (“Unit Weight”)
and Voids in Aggregate
1.1 This test method covers the determination of relative
C127 Test Method for Relative Density (Specific Gravity)
density and absorption of fine aggregates by Method A and
and Absorption of Coarse Aggregate
coarse and blended aggregates by Method B.
C128 Test Method for Relative Density (Specific Gravity)
1.2 A multi-laboratory precision and bias statement for
and Absorption of Fine Aggregate
coarse and combined aggregate tests in this standard has not
C136/C136M Test Method for Sieve Analysis of Fine and
beendevelopedatthistime.Therefore,thisstandardshouldnot
Coarse Aggregates
be used for acceptance or rejection of coarse and combined
C670 Practice for Preparing Precision and Bias Statements
aggregate materials for purchasing purposes.
for Test Methods for Construction Materials
1.3 The values stated in either SI units or inch-pound units C702/C702M Practice for Reducing Samples of Aggregate
to Testing Size
are to be regarded separately as standard. The values stated in
each system are not necessarily exact equivalents; therefore, to D75/D75M Practice for Sampling Aggregates
D3666 Specification for Minimum Requirements for Agen-
ensure conformance with the standard, each system shall be
used independently of the other, and values from the two cies Testing and Inspecting Road and Paving Materials
D4753 Guide for Evaluating, Selecting, and Specifying Bal-
systems shall not be combined. Some values have only SI units
because inch-pound equivalents are not used in practice. ances and Standard Masses for Use in Soil, Rock, and
Construction Materials Testing
1.4 This standard does not purport to address all of the
E691 Practice for Conducting an Interlaboratory Study to
safety concerns, if any, associated with its use. It is the
Determine the Precision of a Test Method
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
3. Summary of Test Method
mine the applicability of regulatory limitations prior to use.
3.1 Sufficient aggregate sample is dried to constant mass.
1.5 This international standard was developed in accor-
For each test, two representative dry aggregate samples of the
dance with internationally recognized principles on standard-
same material are selected for testing. One sample is evacuated
ization established in the Decision on Principles for the
in a vacuum chamber inside a plastic bag and opened under
Development of International Standards, Guides and Recom-
water for rapid saturation of the aggregate. The dry mass and
mendations issued by the World Trade Organization Technical
submerged mass of the sample are used for calculation of
Barriers to Trade (TBT) Committee.
apparent relative density. The second sample of the same
aggregate is tested in a known volume metal pycnometer. The
2. Referenced Documents
known mass of the pycnometer with water, mass of the dry
2.1 ASTM Standards:
aggregate, and mass of the aggregate and pycnometer filled
with water are used for calculation of unsaturated density. The
results from the two samples tested are then used to calculate
This test method is under the jurisdiction of ASTM Committee D04 on Road
absorption and relative density (OD).
and Paving Materials and is the direct responsibility of Subcommittee D04.51 on
Aggregate Tests.
3.2 This test can be completed in less than 30 min and can
Current edition approved May 1, 2021. Published May 2021. Originally
be used for rapid determination of aggregate properties in
approved in 2008. Last previous edition approved in 2014 as D7370/D7370M – 14.
construction testing laboratories.
DOI: 10.1520/D7370_D7370M-14R21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.3 This test can be performed on fine, coarse, and blended
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
(combined) aggregates by using appropriate plastic bag and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. pycnometer sizes.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7370/D7370M − 14 (2021)
4. Significance and Use 5.3 Sample Holder, for water displacement of the sample,
having no sharp edges.
4.1 Relative density (specific gravity) is the characteristic
generally used for calculation of the volume occupied by the 5.4 Vacuum Chamber, with a pump capable of evacuating a
aggregate in various mixtures containing aggregate, including sealed and enclosed chamber to a pressure of 6 mm Hg
portland cement concrete, bituminous concrete, and other [6 Torr], when at sea level. The device shall automatically seal
mixtures that are proportioned or analyzed on an absolute the plastic bag and exhaust air back into the chamber in a
volume basis. Relative density (specific gravity) is also used in controlled manner to ensure proper conformance of the plastic
the computation of voids in aggregate in Test Method C29/ to the specimen. The air exhaust and vacuum operation time
C29M. Relative density (specific gravity) saturated surface dry shall be set at the factory so that the chamber is brought to
(SSD) is used if the aggregate is at SSD, that is, if its atmospheric pressure in 80 to 125 s, after the completion of the
absorption has been satisfied. Conversely, the relative density vacuum operations.
(specificgravity)ovendry(OD)isusedforcomputationswhen
5.5 Vacuum Measurement Gauge, independent of the
the aggregate is dry or assumed to be dry.
vacuum sealing device that could be placed directly inside the
chamber to verify vacuum performance and the chamber door
4.2 Apparentdensityandapparentrelativedensity(apparent
specific gravity) pertain to the solid material making up the sealing condition of the unit. The gauge shall be capable of
reading down to 3 mm Hg [3 Torr] and readable to 61mmHg
constituent particles not including the pore space within the
particles which is accessible to water. [61 Torr].
4.3 Absorptionvaluesareusedtocalculatethechangeinthe 5.6 Plastic Bags, used with the vacuum device shall be one
of the two following sizes. The smaller bags shall have a
mass of an aggregate due to water absorbed in the pore spaces
within the constituent particles, when it is deemed that the minimumopeningof235mm[9.25in.]andmaximumopening
of 260 mm [10.25 in.] and the larger bags shall have a
aggregatehasbeenincontactwithwaterlongenoughtosatisfy
theabsorptionpotential.Thelaboratorystandardforabsorption minimum opening of 375 mm [14.75 in.] and a maximum
opening of 394 mm [15.5 in.]. The bags shall be of plastic
isthatobtainedaftersubmergingdryaggregateforaprescribed
period of time. material, shall be puncture resistant, and shall be impermeable
to water. The bags shall have a minimum thickness of
NOTE1—Thereareothertestmethodsthathavebeenusedandcontinue
0.127 mm [0.005 in.]. The apparent specific gravity for the
to be used to determine these aggregate properties: Test Methods C127
bags shall be provided by the manufacturer.
and C128. This test method may result in values for these properties that
are close to or divergent from values from other test methods.
5.7 Small Metal Pycnometer, with 137 6 0.2 mm [5.375 6
NOTE 2—The quality of the results produced by this standard are
0.01 in.] ID and 89 6 0.40 mm [3.5 6 0.02 in.] height, for
dependent upon the competence of the personnel performing the proce-
testing fine aggregates. The pycnometer shall be machined to
dure and the capability, calibration, and the maintenance of the equipment
be smooth on all surfaces. The inside of the lid shall be
used.Agencies that meet the criteria of Specification D3666 are generally
considered capable of competent and objective testing, sampling,
machined at a 5° angle to create an inverted conical surface.
inspection, etc. Users of this standard are cautioned that compliance with
The pycnometer shall be equipped with a graduated tempera-
Specification D3666 alone does not completely ensure reliable results.
ture strip to allow the user to visually monitor temperature
Reliable results depend on many factors; following the suggestions of
during testing.
Specification D3666 or similar acceptable guideline provides a means of
evaluating and controlling some of those factors.
5.8 Large Metal Pycnometer, with 198 6 0.2 mm [7.776 6
0.01 in.] ID and 114 6 0.8 mm [4.5 6 0.03 in.] height, for
5. Apparatus
testing coarse and blended aggregate. The pycnometer shall be
5.1 Balance, a balance that conforms to Guide D4753. The
machined to be smooth on all surfaces. The inside of the lid
balance shall be sensitive, readable, and accurate to 0.1 g. The shall be machined at a 5° angle to create an inverted conical
balance shall be equipped with suitable apparatus for suspend-
surface. The pycnometer shall be equipped with a graduated
ing the sample in water. temperature strip to allow the user to visually monitor tem-
perature during testing.
5.2 Water Bath, with minimum dimensions (length by width
by depth) of 610 by 460 by 460 mm [24 by 18 by 18 in.] or a
5.9 Fine Aggregate Fixture, for holding and securing the lid
large cylindrical container with a minimum diameter of on the small metal pycnometer from lifting during fine aggre-
460 mm and depth of 460 mm [18 by 18 in.], for completely
gate tests. The fixture shall be provided with a level indicator.
submerging the sample in water while suspended, equipped
5.10 Accessories—Bag cutting knife or scissors, spray
with an overflow outlet for maintaining a constant water level
bottle filled with isopropyl alcohol, a bucket large enough to
and means to maintain the water temperature at 25 6 1 °C [77
allow the pycnometer to be fully submerged in water, water
6 2 °F].
containers to dispense water into pycnometer during testing,
NOTE 3—It is preferable to keep the water temperature constant by
syringe with a needle no larger in diameter than 3 mm
using a temperature-controlled heater. Also, to reduce the chance for the
[0.125 in.], small paint brush, and 25 65mm[1 6 0.2 in.]
bagtotouchthesidesofthewatertank,itispreferabletoelevatethewater
tank to a level at which the sample can be placed on the weighing wide metal spatula.
mechanism while the operator is standing up (waist height), and the
5.11 Rubber Sheets, for protecting the plastic bags against
placement of the sample and the bag in the water tank can easily be
inspected. punctures caused by sharp edges on coarse and blended
D7370/D7370M − 14 (2021)
aggregate samples.The apparent specific gravity for the rubber 6.3 Calibration of the Large Pycnometer:
sheets shall be provided by the manufacturer. 6.3.1 Prior to testing, condition the pycnometer at 25 6
1 °C [77 6 2 °F] by placing it inside a bucket of water that is
5.12 Thermometric Device, for monitoring the temperature
maintained at 25 6 1 °C [77 6 2 °F].
to within 61°C[62 °F].
6.3.2 Remove the pycnometer from the water bucket and
dry it with a towel. Set the pycnometer on a level surface.
6. Verification
6.3.3 Fill the pycnometer with 25 6 1 °C [77 6 2 °F] water
6.1 System Verification:
to approximately 10 mm [0.375 in.] from the top. Using the
6.1.1 The vacuum settings of the vacuum chamber shall be
alcohol spray bottle, spray the surface of the water to remove
verified once every twelve months and after major repairs and
any air bubbles.
after each shipment or relocation.
6.3.4 Gently place the lid on the pycnometer. Using a
6.1.2 Placethegaugeinsidethevacuumchamberandrecord
syringe filled with 25 6 1 °C [77 6 2 °F] water, slowly fill the
the setting while the vacuum unit is operating. The gauge
pycnometer through the large fill hole on the lid post. Make
shouldindicateapressureof6mmHg[6Torr]orless.Theunit
surethesyringetipisfarenoughinthepycnometertobebelow
shall not be used if the gauge reading is above 6 mm Hg
the water level. Gentle application in this step prevents
[6 Torr].
formation of air bubbles inside the pycnometer. Fill the
6.1.3 Vacuum gauge used for verification shall be standard-
pycnometer until water comes out the 3 mm [0.125 in.] hole on
ized for accuracy on annual basis.
the surface of the lid.
NOTE 4—In-line vacuum gauges, while capable of indicating vacuum
6.3.5 Wipe any remaining water from the top of the lid and
performance of the pump, are not suitable for use in enclosed vacuum
sides with a towel. Place the pycnometer on the scale and
chambers and cannot accurately measure vacuum levels.
NOTE5—TheworksheetinAppendixX1isprovidedasanoptionaltool
record the mass to the nearest 0.1 g.
to the user for recording of masses obtained during this test method. Users
6.3.6 Clean the pycnometer and repeat steps 6.3.2 – 6.3.5
may develop their own worksheet or a computer program for this purpose.
two more times and average the calibration masses obtained in
6.2 Calibration of the Small Pycnometer:
6.3.5.
6.2.1 Prior to testing, condition the pycnometer at 25 6
6.3.7 If the range for the three calibration masses is larger
1 °C [77 6 2 °F] by placing it inside a bucket of water that is
than 1 g, then the test is not being run correctly. Check to see
maintained at 25 6 1 °C [77 6 2 °F]. Use a level indicator or
if the fixture is level. Make certain the water injection with the
the provided level to level the fixture.
syringe is done below the pycnometer water surface and is
6.2.2 Remove the pycnometer from the water bucket and
applied gently. Check the water temperature. Check the pyc-
dry it with a towel. Place the pycnometer in the fixture and
nometer temperature. Repeat the above procedure until you
push it back until it makes contact with the stops.
have three masses that are within 1 g range.
6.2.3 Fill the pycnometer with 25 6 1 °C [77 6 2 °F] water
6.3.8 Re-calibrate the pycnometer for each day of use.
to approximately 10 mm [0.375 in.] from the top. Using the
alcohol spray bottle, spray the surface of the water to remove
7. Sampling
b
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