ASTM C1777 - 20

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Designation: C1777 −20
Standard Test Method for
Rapid Determination of the Methylene Blue Value for Fine
Aggregate or Mineral Filler Using a Colorimeter
1
This standard is issued under the ﬁxed designation C1777; 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*
1.1 This test method provides a rapid test to determine the
amount of methylene blue adsorbed by a specimen of ﬁne
aggregate or mineral ﬁller and can be used both in the
laboratory and in the ﬁeld.
1.2 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
standard.
1.3 The text of this standard refers to notes and footnotes
that provide explanatory material. These notes and footnotes
(excluding those in tables and ﬁgures) shall not be considered
as requirements of this standard.
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 appro-
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
2
C125 Terminology Relating to Concrete and Concrete Ag-
gregates
C702/C702M Practice for Reducing Samples of Aggregate
to Testing Size
D75/D75M Practice for Sampling Aggregates
E11 Speciﬁcation for Woven Wire Test Sieve Cloth and Test
Sieves
2.2 Other Standards:
AASHTO T330 Standard Method of Test for the Qualitative
Detection of Harmful Clays of the Smectite Group in
Aggregates Using Methylene Blue
3
EN 933-9 Tests for geometrical properties of aggregates.
Part 9: Assessment of ﬁnes – Methylene blue test
4
3. Terminology
3.1 Deﬁnitions:
3.1.1 For deﬁnitions of terms used in this standard, refer to
Terminology C125.
3.2 Deﬁnitions of Terms Speciﬁc to This Standard:
3.2.1 mineral ﬁller, n—a ﬁnely divided mineral product at
least 65 % of which passes the 75-µm sieve.
4. Summary of Test Method
4.1 A specimen of ﬁne aggregate or mineral ﬁller is com-
bined with a methylene blue solution of known concentration
and mixed for a prescribed period of time. The specimen
adsorbs some of the methylene blue from solution. The
resulting mixture is ﬁltered and a portion of the ﬁltered solution
is diluted by a ﬁxed amount. A colorimeter is used to determine
the absorbance of the diluted solution, from which the concen-
tration of methylene blue prior to dilution is calculated. The
change in concentration of methylene blue before and after
mixing with ﬁne aggregate or mineral ﬁller is converted to a
methylene blue value and reported in units of mg/g.
5. Signiﬁcance and Use
5.1 This test method is used to determine rapidly the amount
of methylene blue adsorbed by a specimen of ﬁne aggregate or
mineral ﬁller. The result is reported as a methylene blue value
in units of mg of methylene blue adsorbed per g of ﬁne
aggregate or mineral ﬁller. The methylene blue value is a
1
This test method is under the jurisdiction of ASTM Committee C09 on
Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee
C09.20 on Aggregates.
Current edition approved June 1, 2020. Published July 2020. Originally approved
in 2013. Last previous edition approved in 2015 as C1777 – 15. DOI: 10.1520/
C1777-20.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3
Available from American Association of State Highway and Transportation
Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,
http://www.transportation.org.
4
Available from European Committee for Standardization, Avenue Marnix 17,
B-1000 Brussels, Belgium.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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.

function of the amount and characteristics of clay minerals

present in the test specimen. High methylene blue values

indicate increased potential for diminished ﬁne aggregate or

mineral ﬁller performance in a cementitious mixture due to the

presence of clays.

NOTE 1—Results from this test method are not expected to be correlated

with those obtained using AASHTO T 330 or EN 933-9. These three test

methods are likely to give very different numerical values even though the

units are the same. The AASHTO T 330 test is performed only on the

fraction of an aggregate passing the 75 µm sieve, the EN 933-9 test is

performed only on the fraction ﬁner than 2 mm, and this test is performed

on the fraction ﬁner than the 4.75 mm sieve. Therefore, when testing the

same ﬁne aggregate source, the AASHTO test method would give the

highest methylene blue value because any clay present in the specimen

would be concentrated in the fraction ﬁner than the 75 µm sieve. The

AASHTO and EN test methods do not take into account the amount of

material passing the 75 µm sieve or 2 mm sieve, respectively. For

example, a ﬁne aggregate with high methylene blue value measured by the

AASHTO method but low percentage passing the 75 µm sieve may have

less effect on concrete performance than a ﬁne aggregate with low

methylene blue value measured by the AASHTO method but a high

percentage passing the 75 µm sieve. In contrast, this test method expresses

methylene blue value based on the entire ﬁne aggregate or mineral ﬁller

specimen. Additionally, the AASHTO and EN test methods use titration to

determine the amount of methylene blue of known concentration that is

adsorbed by a specimen and require the operator to visually determine the

end point of the test. In contrast, this test method uses a colorimeter to

detect the change in concentration of methylene blue solution before and

after being mixed with the ﬁne aggregate or mineral ﬁller specimen.

NOTE 2—Recommendations for maximum methylene blue values for

speciﬁc applications are not provided in this test method. Maximum

methylene blue values should be established based on successful perfor-

mance of ﬁne aggregate or mineral ﬁller in the applications under

consideration.

6. Interferences

6.1 Methylene blue will degrade when exposed to light.

Store in darkness. No appreciable degradation occurs during

the time it takes to complete the test method.

6.2 Methylene blue will stain glassware and plastic ware.

Therefore, do not reuse such apparatus.

7. Apparatus

7.1 4.75-mm sieve conforming to Speciﬁcation E11.

7.2 Mass balance having a capacity of 50 g or more and

capable of measuring to the nearest 0.1 g or less.

7.3 Micropipette capable of measuring to the nearest 1 µL.

7.4 Colorimeter capable of reading absorbance of a speci-

men at a wavelength of 610 61 nm at operating temperatures

of at least 0 to 50ºC. The colorimeter shall be able to read

absorbance between zero and the absorbance associated with a

0.144 % mass concentration of methylene blue solution.

7.5 Disposable items for each test—two plastic 50-mL test

tubes, one plastic 1-mL vial, one 3-mL syringe with Luer-Lok

adapter, one 0.2-µm syringe ﬁlter, one colorimeter glass cuvette

(or sample cell), one micropipette tip, and two transfer pipettes.

7.6 Additional disposable items for conﬁrming methylene

blue starting concentration—plastic 50-mL test tube, colorim-

eter glass cuvette, micropipette tip, and transfer pipette.

7.7 Additional disposable items for standardizing the

colorimeter—plastic 50-mL test tube, colorimeter glass

cuvette, micropipette tip, and transfer pipette.

7.8 Drying apparatus—A ventilated oven capable of main-

taining a uniform temperature of 110 65°C. Other suitable

drying apparatuses shall be permitted, such as an electric hot

plate or heat lamp. The temperature of the specimen shall not

exceed 150°C. In cases where the ﬁne aggregate or mineral

ﬁller itself is altered by temperature greater than 115°C, use a

ventilated, controlled-temperature oven at 110 65°C.

NOTE 3—Drying by means other than a ventilated oven may be

appropriate for ﬁeld use.

8. Reagents and Materials

8.1 Purity of reagents—reagent grade methylene blue shall

be used in all tests.

8.2 Purity of water—references to water shall be understood

to mean distilled or deionized water.

8.3 Methylene blue test solution—a 0.50 % mass concentra-

tion methylene blue solution based on mass of trihydrate

methylene blue in water.

NOTE 4—Methylene blue is available in both anhydrous and trihydrate

form and can also be obtained in solution form. This test is based on the

mass of the trihydrate form.

9. Sampling, Test Specimens, and Test Units

9.1 Sample ﬁne aggregate in accordance to Practice D75/

D75M.

9.2 Thoroughly mix the sample and reduce it as necessary

using the applicable procedures in Practice C702/C702M.

9.3 If it appears necessary, dampen the material to avoid

segregation or loss of ﬁnes during specimen preparation.

9.4 Obtain at least 30 g of material passing the 4.75-mm

sieve in the following manner:

9.4.1 Separate the sample on the 4.75-mm sieve by means

of a lateral and vertical motion of the sieve, accompanied by a

jarring action so as to keep the sample moving continuously

over the surface of the sieve. Continue the sieving until not

more than 1 mass % of the residue passes the sieve during the

1-min sieving operation. Perform the sieving operation either

by hand or by a mechanical apparatus. When thoroughness of

mechanical sieving is being determined, test by the hand

method described above using a single layer of material on the

sieve.

9.4.2 Break down any lumps of material in the coarse

fraction to pass the 4.75-mm sieve. Use a mortar and rubber-

covered pestle or any other means that will not fracture

aggregate particles. Add this additional material passing the

sieve to the separated ﬁne portion of the sample and mix

thoroughly.

9.5 Dry the test specimen to constant mass by means of the

selected source of heat, and cool to room temperature before

testing. The sample is thoroughly dry when further heating

causes, or would cause, less than 0.1 g additional loss in mass.

9.6 Repeat the procedures in 9.4 and 9.5 to obtain three test

specimens.

C1777 − 20

10. Standardization
10.1 Standardization of the colorimeter for the relationship
between absorbance and the methylene blue concentration—
Insert a glass cuvette approximately
2
⁄
3
full with water into the
colorimeter and zero the instrument. Use the micropipette to
transfer a 130 61 µL aliquot of 0.50 % mass methylene blue
solution to a 50-mL test tube. Dilute the aliquot with water so
that the net mass of the diluted solution is 45.0 60.1 g. Place
a cap on the test tube and gently shake the diluted solution for
561 s. Using a new transfer pipette, ﬁll a glass colorimeter
cuvette approximately
2
⁄
3
full with the diluted solution. Wipe
the cuvette with a clean towel if necessary to remove any
marks. Insert the cuvette with the diluted methylene blue
solution into the colorimeter and measure the absorbance.
Rotate the cuvette within the meter a quarter revolution and
take another measurement. Repeat until four measurements are
made. Calculate the average of the four values, and record as
A
std
to the nearest 0.01 A. Perform this standardization for each
colorimeter at least once every 6 months or whenever the light
source or batteries are replaced (if applicable). Use a freshly-
made 0.5 % mass methylene blue test solution for standardiza-
tion of the colorimeter.
10.2 Determination of actual initial methylene blue
concentration—Before testing the ﬁne aggregate or mineral
ﬁller, determine the actual initial concentration of methylene
blue test solution that will be used. Insert a cuvette approxi-
mately
2
⁄
3
ﬁlled with water into the colorimeter and zero the
instrument. Use the micropipette to transfer a 130 61µL
aliquot of the methylene blue solution to a 50-mL test tube.
Dilute the aliquot with water so that the net mass of the diluted
solution is 45.0 60.1 g. Cap the test tube and gently shake the
diluted solution for 5 61 s. Follow the procedure in 10.1 to
obtain four values of absorbance of the diluted test solution.
Calculate the average of the four values, and record as A
i
.
Determine the actual initial concentration of the test solution,
C
i
, prior to dilution, using the following equation:
C
i
5
~
0.50 %
!
3A
i
A
std
(1)
Repeat the process with two more aliquots. Calculate the
average of the three values and record this as the average initial
concentration of methylene blue in the test solution to the
nearest 0.01 %. Perform this determination of actual initial
concentration each day or whenever a new source or batch of
methylene blue test solution is used.
NOTE 5—10.2 is conducted to ensure the methylene blue solution to be
used in the test is at the correct initial concentration.
10.3 Adjustment of initial concentration of methylene blue
solution—If the actual initial concentration is below 0.48 %,
discard and prepare a new test solution. If the actual initial
concentration is greater than 0.50 %, add sufficient water to
adjust to 0.50 %.
11. Procedure
11.1 Test Specimens—Weigh 20.0 60.1 g of dry ﬁne
aggregate or mineral ﬁller as obtained in Section 9and record
the actual mass of the specimen. Tare a 50-mL test tube, weigh
30.0 60.1 g of methylene blue test solution directly into the
test tube, and record the actual mass of solution. Add the
weighed aggregate to the methylene blue solution, ensuring all
ﬁnes are incorporated.
11.2 Mixing—Cap the test tube and shake the mixture by
hand for 60 61 s and allow to rest for 180 65 s. Shake the
mixture again for 60 61 s to complete the mixing process.
11.3 Filtration—Remove the plunger from the 3-mL-
syringe and attach the 0.2-µm syringe ﬁlter. Using a transfer
pipette, add approximately 2 mL of the specimen mixture to the
syringe and replace the plunger. Push the plunger slowly until
0.5 to 1 mL of the ﬁltered solution is collected in a new 1-mL
vial.
11.4 Dilution—Using the micropipette, transfer 130 61µL
of the ﬁltered solution into a new 50-mL test tube. Dilute the
ﬁltered solution with water until the net mass is 45.0 60.1 g.
Cap the 50-mL test tube and gently shake the diluted solution
for 5 61 s. Using a new transfer pipette, ﬁll a glass colorimeter
cuvette approximately
2
⁄
3
full with the diluted solution.
11.5 Colorimeter zero adjustment—Place a cuvette ﬁlled
approximately
2
⁄
3
with water into the colorimeter and zero the
instrument.
11.6 Absorbance measurement—Remove the cuvette ﬁlled
with water and replace with the cuvette ﬁlled with the diluted
solution. Measure and record the absorbance to the nearest 0.01
A. Rotate the cuvette within the colorimeter a quarter revolu-
tion and take another measurement. Repeat a total of four times
and calculate the average of the four values; record as A
f
.
11.7 Calculation of undiluted ﬁnal methylene blue
concentration—Using the average value of A
f
from 11.6,
calculate the ﬁnal methylene blue concentration, before
dilution, to the nearest 0.01 % using the following equation:
C
f
5
~
0.50 %
!
3A
f
A
std
(2)
11.8 Replicate testing—Repeat steps 11.1 through 11.7 on
two additional specimens.
12. Calculation of Methylene Blue Value
12.1 For each determination of the ﬁnal concentration of
methylene blue solution, determine the methylene blue value
(MBV) in units of mg/g by using the following equation:
MBV 5
~
C
i
2C
f
!~
M
MB
!
M
FM
310 (3)
where:
C
i
= average actual initial concentration of methylene
blue test solution in percent as determined in 10.2,
C
f
= ﬁnal concentration of methylene blue solution in
percent as determined in 11.7,
M
MB
= mass of methylene blue test solution as measured in
11.1, and
M
FM
= mass of ﬁne aggregate or mineral ﬁller as measured
in 11.1.
12.2 Calculate the methylene blue value as the average of
three individual test determinations from 12.1.
C1777 − 20
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摘要：

ASTM C1777-20 是由美国材料与试验协会（ASTM）发布的一项标准测试方法，专门用于通过稳态热流技术测量材料的热导率或热传导性能。该标准适用于均匀或非均匀的固体材料，尤其适用于评估隔热材料、建筑构件以及电子元件的热性能。通过精确控制温度梯度和热流密度，ASTM C1777-20 提供了可重复、可比较的实验室数据，帮助工程师和质量控制人员验证材料的热设计参数并确保其符合建筑节能或工业应用要求。该标准替代了早期版本，在测试装置校准、样品制备条件以及数据处理方法上进行了优化，进一步提升了测量

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