ASTM C67/C67M-23a

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: C67/C67M − 23a American Association State Highway and Transportation
Officials Standard
AASHTO No.: T 32-70
Standard Test Methods for
Sampling and Testing Brick and Structural Clay Tile
This standard is issued under the fixed designation C67/C67M; 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 U.S. Department of Defense.
1. Scope*
Section Heading Section
Measurement of Size 13
1.1 These test methods cover procedures for the sampling
Measurement of Warpage 14
and testing of brick and structural clay tile. Although not
Measurement of Length Change 15
necessarily applicable to all types of units, tests include Initial Rate of Absorption (Suction) (Field Test) 16
Measurement of Void Area in Cored Units 17
modulus of rupture, compressive strength, absorption, satura-
Measurement of Void Area in Deep Frogged Units 18
tion coefficient, effect of freezing and thawing, efflorescence,
Measurement of Out of Square 19
Measurement of Shell and Web Thickness 20
initial rate of absorption and determination of weight, size,
Breaking Load 21
warpage, length change, and void area. (Additional methods of
Imperviousness Test (of Ceramin Glazes) 22
test pertinent to ceramic glazes include imperviousness, chemi-
Chemical Resistance Test (of Ceramic Glazes) 23
cal resistance, opacity, and resistance to crazing. Autoclaved Crazing Test (of Ceramic Glazes) 24
Opacity Test (of Ceramic Glazes) 25
1.2 The text of this standard references notes and footnotes
Precision and Bias 26
Keywords 27
which provide explanatory material. These notes and footnotes
Safety Precautions for Autoclave Equipment and Appendix X1
(excluding those in tables and figures) shall not be considered
Operation
as requirements of the standard.
1.5 This standard does not purport to address all of the
NOTE 1—The testing laboratory performing this test method should be
safety concerns, if any, associated with its use. It is the
evaluated in accordance with Practice C1093.
responsibility of the user of this standard to establish appro-
1.3 The values stated in either SI units or inch-pound units
priate safety, health, and environmental practices and deter-
are to be regarded separately as standard. The values stated in
mine the applicability of regulatory limitations prior to use.
each system are not necessarily exact equivalents; therefore, to
1.6 This international standard was developed in accor-
ensure conformance with the standard, each system shall be
dance with internationally recognized principles on standard-
used independently of the other, and values from the two
ization established in the Decision on Principles for the
systems shall not be combined.
Development of International Standards, Guides and Recom-
1.4 These test methods include the following sections:
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
Section Heading Section
Scope 1
Referenced Documents 2
2. Referenced Documents
Terminology 3
2.1 ASTM Standards:
Sampling 4
Specimen Preparation 5
C150/C150M Specification for Portland Cement
Modulus of Rupture (Flexure Test) 6
C1093 Practice for Accreditation of Testing Agencies for
Compressive Strength 7
Absorption 8 Masonry
Freezing and Thawing 9
C1232 Terminology for Masonry
Initial Rate of Absorption (Suction) (Laboratory 10
E4 Practices for Force Calibration and Verification of Test-
Test)
ing Machines
Efflorescence 11
Weight Per Unit Area 12
E6 Terminology Relating to Methods of Mechanical Testing
E177 Practice for Use of the Terms Precision and Bias in
These test methods are under the jurisdiction of Committee C15 on Manufac-
tured Masonry Units and is the direct responsibility of Subcommittee C15.02 on
Brick and Structural Clay Tile. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved June 1, 2023. Published June 2023. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1937. Last previous edition approved in 2023 as C67/C67M – 23. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C0067_C0067M-23A. the ASTM website.
*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
C67/C67M − 23a
ASTM Test Methods free from drafts, unstacked, with separate placement, for a
E691 Practice for Conducting an Interlaboratory Study to period of at least 4 h and until the surface temperature is within
Determine the Precision of a Test Method 5°F [2.8°C] of the drying room temperature. Do not use
specimens noticeably warm to the touch for any test requiring
3. Terminology
dry units. The specimens shall be stored in the drying room
3.1 Definitions—For definitions relating to sampling and with the required temperature and humidity maintained until
tested.
testing brick, refer to Terminology E6 and Terminology C1232.
5.1.2.1 An alternative method of cooling the specimens to
4. Sampling
approximate room temperature is permitted as follows: Store
units, unstacked, with separate placement, in a ventilated room
4.1 Selection and Preparation of Test Specimens—For the
maintained at a temperature of 75 6 15°F [24 6 8°C], with a
purpose of these tests, full-size brick, tile, or solid masonry
relative humidity between 30 and 70 % for a period of 4 h and
units shall be selected by the purchaser or by the purchaser’s
until the surface temperature is within 5°F [2.8°C] of the
authorized representative. Specimens shall be representative of
ventilated room temperature, with a current of air from an
the lot of units from which they are selected and shall include
electric fan passing over them for a period of at least 2 hours.
specimens representative of the complete range of colors,
The specimens shall be stored in the ventilated room with the
textures, and sizes. Specimens shall be free of or brushed to
required temperature and humidity maintained until tested.
remove dirt, mud, mortar, or other foreign materials unassoci-
ated with the manufacturing process. Brushes used to remove
5.2 Weight Determination:
foreign material shall have bristles of plastic (polymer) or
5.2.1 Weigh five full size specimens that have been dried
horsehair. Wire brushes shall not be used for preparing speci-
and cooled (see 5.1). The scale or balance used shall have a
mens for testing. Specimens exhibiting foreign material that is
capacity of not less than 3000 g and shall be sensitive to 0.5 g.
not removed by brushing shall be discarded to ensure that
5.2.2 Report results separately for each specimen to the
damaged or contaminated specimens are not tested.
nearest 0.1 g, with the average of all specimens tested to the
4.2 Number of Specimens: nearest 0.1 g.
4.2.1 Brick—For the modulus of rupture, compressive
5.3 Removal of Silicone Coatings from Brick Units—The
strength, abrasion resistance, and absorption determinations, at
silicone coatings intended to be removed by this process are
least ten individual brick shall be selected for lots of 1 000 000
any of the various polymeric organic silicone compounds used
brick or fraction thereof. For larger lots, five additional
for water-resistant coatings of brick units. Heat the brick at 950
specimens shall be selected from each additional 500 000 brick
6 50°F [510 6 28°C] in an oxidizing atmosphere for a period
or fraction thereof. Additional specimens are taken at the
of not less than 3 hours. The rate of heating and cooling shall
discretion of the purchaser.
not exceed 300°F [149°C] per hour.
4.2.2 Structural Clay Tile—For the weight determination
NOTE 2—Additional specimen preparation requirements for specific
and for compressive strength and absorption tests, at least five
tests are indicated in the individual test methods.
tile shall be selected from each lot of 250 tons [250 mt] or
fraction thereof. For larger lots, five additional specimens shall
6. Modulus of Rupture (Flexure Test)
be tested for each 500 tons [500 mt] or fraction thereof. In no
6.1 Test Specimens—The test specimens shall consist of
case shall less than five tile be taken. Additional specimens are
whole full-size units that have been dried and cooled (see 5.1).
taken at the discretion of the purchaser.
4.2.3 Ceramic Glazed Units—For imperviousness, chemical Five such specimens shall be tested.
resistance, crazing, and opacity tests, select a representative of
6.2 Procedure:
10 units for lots of 1 000 000 units, or fraction thereof. For
6.2.1 Support the test specimen flatwise unless specified and
larger lots, select five additional specimens from each addi-
reported otherwise (that is, apply the load in the direction of the
tional 500 000 units, or fraction thereof. Do not use specimens
depth of the unit) on a span approximately 1 in. [25 mm] less
selected for 4.2.1 or 4.2.2.
than the basic unit length and loaded at midspan. Specimens
4.3 Identification—Each specimen shall be marked so that it having recesses (panels or depressions) shall be placed so that
is identifiable at any time. Markings shall cover not more than such recesses are on the compression side. Apply the load to
5 % of the superficial area of the specimen. the upper surface of the specimen through a steel bearing plate
1 1
⁄4 in. [6 mm] in thickness and 1 ⁄2 in. [38 mm] in width and of
5. Specimen Preparation
a length at least equal to the width of the specimen.
5.1 Drying and Cooling: 6.2.2 Make sure the supports for the test specimen are free
to rotate in the longitudinal and transverse directions of the test
5.1.1 Drying—Dry the test specimens in a ventilated oven at
221 to 239°F [105 to 115°C] for not less than 24 h and until specimen and adjust them so that they will exert no force in
these directions.
two successive weighings at intervals of 2 h show an increment
of loss not greater than 0.2 % of the last previously determined 6.2.3 Speed of Testing—The rate of loading shall not exceed
weight of the specimen. 2000 lbf [9000 N]/min. This requirement is considered as
5.1.2 Cooling—After drying, cool the specimens in a drying being met when the speed of the moving head of the testing
room maintained at a temperature of 75 6 15°F [24 6 8°C], machine immediately prior to application of the load is not
with a relative humidity between 30 and 70 %. Store the units more than 0.05 in. [1.25 mm]/min.
C67/C67M − 23a
6.3 Calculation and Report: plate, such as glass or machined metal. The casting surface
6.3.1 Calculate and report the modulus of rupture of each plate shall be plane within 0.003 in. [0.1 mm] in 16 in. [400
specimen to the nearest 1 psi [0.01 MPa] as follows: mm] and sufficiently rigid; and so supported that it will not be
measurably deflected during the capping operation. Lightly
S 5 3W~l/2 2 x!/bd (1)
coat it with oil or other suitable material. Repeat this procedure
where:
with the other shellacked surface. Take care that the opposite
S = modulus of rupture of the specimen at the plane of bearing surfaces so formed will be approximately parallel and
failure, lb/in. [Pa], perpendicular to the vertical axis of the specimen and the
W = maximum load indicated by the testing machine, lbf
thickness of the caps will be approximately the same and not
[N],
exceeding ⁄8 in. [3 mm]. Age the caps at least 24 h before
l = distance between the supports, in. [mm],
testing the specimens.
b = net width, (face to face minus voids), of the specimen
NOTE 3—A rapid-setting industrial type gypsum is frequently used for
at the plane of failure, in. [mm],
capping.
d = depth, (bed surface to bed surface), of the specimen at
the plane of failure, in. [mm], and
7.2.4 Sulfur-Filler Capping—Use a mixture containing 40
x = average distance from the midspan of the specimen to
to 60 weight % sulfur, the remainder being ground fire clay or
the plane of failure measured in the direction of the
other suitable inert material passing a No. 100 [150-μm] sieve
span along the centerline of the bed surface subjected to
with or without plasticizer. The casting surface plate require-
tension, in. [mm].
ments shall be as described in 7.2.3. Place four 1-in. [25-mm]
square steel bars on the surface plate to form a rectangular
6.3.2 Calculate and report the average of the modulus of
mold approximately ⁄2 in. [12.5 mm] greater in either inside
rupture determinations to the nearest 1 psi [0.01 MPa].
dimension than the specimen. Heat the sulfur mixture in a
thermostatically controlled heating pot to a temperature suffi-
7. Compressive Strength
cient to maintain fluidity for a reasonable period of time after
7.1 Test Specimens:
contact with the surface being capped. Take care to prevent
7.1.1 Brick—The test specimens shall consist of half brick
overheating, and stir the liquid in the pot just before use. Fill
units that have been dried and cooled (see 5.1), the full height
the mold to a depth of ⁄4 in. [6 mm] with molten sulfur
and width of the unit, with a length equal to one half the full
material. Place the surface of the unit to be capped quickly in
length of the unit 61 in. [25 mm], except as described below.
the liquid, and hold the specimen so that its vertical axis is at
When the test specimen, described above, exceeds the testing
right angles to the capping surface. The thickness of the caps
machine capacity, the test specimens shall consist of dry pieces
shall be approximately the same. Allow the unit to remain
of brick, the full height and width of the unit, with a length not
undisturbed until solidification is complete. Allow the caps to
less than one quarter of the full length of the unit, and with a
cool for a minimum of 2 h before testing the specimens.
gross cross-sectional area perpendicular to bearing not less
2 2
7.3 Procedure:
than 14 in. [90 cm ]. Test specimens shall be obtained by any
method that will produce, without shattering or cracking, a 7.3.1 Test brick specimens flatwise (that is, the load shall be
specimen with approximately plane and parallel ends. Five
applied perpendicular to the bed surface of the brick with the
specimens shall be tested. brick in the stretcher position). Test structural clay tile speci-
7.1.2 Structural Clay Tile—Test five tile specimens that
mens in a position such that the load is applied in the same
have been dried and cooled (see 5.1) in a bearing bed length direction as in service. Center the specimens under the spheri-
equal to the width 61 in. [25 mm]; or test full-size units.
cal upper bearing within ⁄16 in. [2 mm].
7.3.2 The testing machine shall conform to the requirements
7.2 Capping Test Specimens:
of Practices E4.
7.2.1 All specimens shall be dry and cool within the
meaning of 5.1.1 and 5.1.2 before any portion of the capping 7.3.3 The upper bearing shall be a spherically seated,
procedure is carried out. hardened metal block firmly attached at the center of the upper
7.2.2 Fill recessed or paneled surfaces that will become head of the machine. The center of the sphere shall lie at the
bearing surfaces during the compression test with a mortar center of the surface of the block in contact with the specimen.
composed of 1 part by weight of quick-hardening cement The block shall be closely held in its spherical seat, but shall be
conforming to the requirements for Type III cement of Speci- free to turn in any direction, and its perimeter shall have at least
fication C150/C150M, and 2 parts by weight of sand. Age the ⁄4 in. [6 mm] clearance from the head to allow for specimens
specimens at least 48 h before capping them. Where the recess whose bearing surfaces are not exactly parallel. The diameter
exceeds ⁄2 in. [12.5 mm], use a brick or tile slab section or of the bearing surface shall be at least 5 in. [125 mm]. Use a
metal plate as a core fill. Cap the test specimens using one of hardened metal bearing block beneath the specimen to mini-
the two procedures described in 7.2.3 and 7.2.4. mize wear of the lower platen of the machine. The bearing
7.2.3 Gypsum Capping—Coat the two opposite bearing block surfaces intended for contact with the specimen shall
surfaces of each specimen with shellac and allow to dry have a hardness not less than HRC60 (HB 650). These surfaces
thoroughly. Bed one of the dry shellacked surfaces of the shall not depart from plane surfaces by more than 0.001 in.
specimen in a thin coat of neat paste of calcined gypsum [0.03 mm]. When the bearing area of the spherical bearing
(plaster of paris) that has been spread on an oiled nonabsorbent block is not sufficient to cover the area of the specimen, place
C67/C67M − 23a
a steel plate with surfaces machined to true planes within 6 8.3.1.2 Saturation—Submerge the dry, cooled specimen,
0.001 in. [0.03 mm], and with a thickness equal to at least one without preliminary partial immersion, in clean water (soft,
third of the distance from the edge of the spherical bearing to distilled or rain water) at 60 to 86°F [15.5 to 30°C] for the
the most distant corner between the spherical bearing block and specified time. Remove the specimen, wipe off the surface
the capped specimen. water with a damp cloth and weigh the specimen. Complete
7.3.4 Speed of Testing—Apply the load to the specimens in weighing of each specimen within 5 min after removing the
accordance with 7.3.4.1 or 7.3.4.2. specimen from the bath.
7.3.4.1 Speed of Testing—Time Limit—Apply the load, up to
8.3.2 Calculation and Report:
one half of the expected maximum load, at any convenient rate,
8.3.2.1 Calculate and report the cold water absorption of
after which, adjust the controls of the machine so that the
each specimen to the nearest 0.1 % as follows:
remaining load is applied at a uniform rate in not less than 1
Absorption, % 5 100 W 2 W /W (3)
~ !
s d d
nor more than 2 min.
7.3.4.2 Speed of Testing—Rate Limit—Apply the load, up to where:
one half of the expected maximum load, at any convenient rate,
W = dry weight of the specimen, and
d
after which, the remaining load is applied at a rate of
W = saturated weight of the specimen after submersion in
s
3000 6 500 lbf ⁄s [1360 6 228 kg ⁄s].
cold water.
7.4 Calculation and Report:
8.3.2.2 Calculate and report the average cold water absorp-
7.4.1 Calculate and report the compressive strength of each
tion of all specimens to the nearest 0.1 %.
specimen to the nearest 10 psi [70 kPa] as follows:
8.4 1-h, 2-h, and 5-h Boiling Tests:
Compressive strength, C 5 W/ A (2)
8.4.1 Test Specimens—The test specimens shall be the same
where: five specimens used in the 5-h or 24-h cold-water submersion
test where required and shall be used in the state of saturation
C = compressive strength of the specimen, lb/in. [or kg/
2 4
existing at the completion of that test.
cm ] [or Pa·10 ],
W = maximum load, lbf, [or kgf] [or N], indicated by the 8.4.1.1 Dry and cool the test specimens in accordance with
testing machine, and 5.1 when performing the boiling water absorption test without
A = average of the gross areas of the upper and lower
previously conducting the cold water absorption test.
2 2
bearing surfaces of the specimen, in. [or cm ].
8.4.2 Procedure:
NOTE 4—When compressive strength is to be based on net area
8.4.2.1 Return the specimen that has been subjected to the
(example: clay floor tile), substitute for A in the above formula the net
cold-water submersion to the bath, and subject it to the boiling
2 2
area, in in. [or cm ], of the fired clay in the section of minimum area
test as described in 8.4.2.2.
perpendicular to the direction of the load.
8.4.2.2 Submerge the specimen in clean water (soft, distilled
7.4.2 Calculate and report the average of the compressive
or rain water) at 60 to 86°F [15.5 to 30°C] in such a manner
strength determinations to the nearest 10 psi [70 kPa].
that water circulates freely on all sides of the specimen. Heat
the water to boiling, within 1 h, boil continuously for specified
8. Absorption
time, and then allow to cool to 60 to 86°F [15.5 to 30°C] by
8.1 Accuracy of Weighings:
natural loss of heat. Remove the specimen, wipe off the surface
8.1.1 Brick—The scale or balance used shall have a capacity
water with a damp cloth, and weigh the specimen. Complete
of not less than 2000 g, and shall be sensitive to 0.5 g.
weighing of each specimen within 5 min after removing the
8.1.2 Tile—The balance used shall be sensitive to within
specimen from the bath.
0.2 % of the weight of the smallest specimen tested.
8.4.2.3 When the tank is equipped with a drain so that water
8.2 Test Specimens:
at 60 to 86°F [15.5 to 30°C] passes through the tank continu-
8.2.1 Brick—The test specimens shall consist of half brick
ously and at such a rate that a complete change of water takes
conforming to the requirements of 7.1.1. Five specimens shall
place in not more than 2 min, make weighings at the end of
be tested.
1 hour.
8.2.2 Tile—The specimens for the absorption test shall
8.4.3 Calculation and Report:
consist of five tile or three representative pieces from each of
8.4.3.1 Calculate and report the boiling water absorption of
these five tile. Two of the three representative pieces shall be
each specimen to the nearest 0.1 % as follows:
taken from the shells and one from an interior web, the weight
Absorption, % 5 100 W 2 W /W (4)
~ !
b d d
of each piece being not less than 225 g. The specimens shall
have had their rough edges or loose particles ground off. Pieces
where:
taken from tile that have been subjected to compressive
W = dry weight of the specimen, and
d
strength tests shall be free of cracks due to failure in compres-
W = saturated weight of the specimen after submersion in
b
sion.
boiling water.
8.3 5-h and 24-h Submersion Tests:
8.4.3.2 Calculate and report the average boiling water ab-
8.3.1 Procedure:
sorption of all specimens to the nearest 0.1 %.
8.3.1.1 Dry and cool the test specimens in accordance with
5.1 and weigh each one in accordance with 5.2. 8.5 Saturation Coeffıcient:
C67/C67M − 23a
8.5.1 Calculate and report the saturation coefficient of each manual operation on a 24-h a day basis or for the storage of all
specimen to the nearest 0.01 as follows: specimens in a frozen condition when the equipment is not in
operation.
Saturation coefficient 5 W 2 W / W 2 W (5)
~ ! ~ !
c 24 d b 5 d
~ ! ~ !
9.1.3.2 Support each specimen at the bottom of its container
where:
in such a way that the temperature of the heat-exchanging
medium will not be transmitted directly through the bottom of
W = dry weight of the specimen,
d
W = saturated weight of the specimen after 24-h sub-
the container to the full area of the bottom of the specimen,
c(24)
mersion in cold water, and thereby subjecting it to conditions substantially different from
W = saturated weight of the specimen after 5-h submer-
the remainder of the specimen.
b(5)
sion in boiling water.
NOTE 6—A single layer of ⁄8-in. [3-mm] wire zig-zagging every one to
two inches across the bottom of the container has been found adequate for
8.5.2 Calculate and report the average saturation coefficient
supporting specimens.
of all specimens to the nearest 0.01.
9.1.3.3 Temperature-Measuring Equipment, consisting of
9. Freezing and Thawing thermometers, resistance thermometers, or thermocouples, ca-
pable of measuring the temperature within the specimen
NOTE 5—The freezing and thawing test of specimens can be performed
using two different methods, shown below as Method A and Method B.
chamber and at the centers of control specimens to within 2°F
Method A is the original method in C67/C67M that typically requires a
[1°C].
minimum of 12 ⁄2 weeks to complete. Method B is an automated method
based on C666/C666M that has been adapted to testing brick and requires 9.2 Test Specimens:
an apparatus utilizing specialized equipment but provides the same
9.2.1 Specimens Method A:
pass/fail performance as Method A in typically 2 ⁄2 to 3 weeks of testing
9.2.1.1 Brick—The test specimens shall consist of half brick
with failure responses that better mimic those in actual conditions. Some
with approximately plane and parallel ends. When necessary,
procedures are specific to only one method and are identified under that
method. The information contained in each of these subsections is specific smooth any rough ends by trimming off a thin section with a
to that method only.
masonry saw. Specimens damaged in the sawing process shall
be discarded. The specimens shall be free from shattering or
9.1 Apparatus:
unsoundness, visually observed, resulting from the flexure or
9.1.1 Apparatus—Both Methods:
from the absorption tests. Additionally, prepare specimens by
9.1.1.1 Balance, having a capacity of not less than 2000 g
removing all loosely adhering particles, sand or edge shards
and sensitive to 0.5 g.
from the surface or cores. Test five specimens.
9.1.1.2 Drying Oven that provides a free circulation of air
9.2.1.2 Structural Clay Tile—The test specimens shall con-
through the oven and is capable of maintaining a temperature
sist of five tile or of a cell not less than 4 in. [101.6 mm] in
between 221 and 239°F [105 and 115°C].
length sawed from each of the five tile. Specimens damaged in
9.1.1.3 Drying Room, maintained at a temperature of 75 6
the sawing process shall be discarded.
15°F [24 6 8°C], with a relative humidity between 30 and
9.2.2 Specimens Method B:
70 %, and free from drafts.
9.2.2.1 Brick—The test specimens shall consist of full brick
2 2
9.1.2 Apparatus—Method A:
or a partial brick with a minimum of 15 in. [110 cm ] of
finished stretcher face. Specimens damaged in the sawing
9.1.2.1 Compressor, Freezing Chamber, and Circulator of
such design and capacity that the temperature of the air in the process shall be discarded. The specimens shall be free from
shattering or unsoundness, visually observed, resulting from
freezing chamber will not exceed 16°F [−9°C] 1 h after
introducing the maximum charge of units, initially at a tem- the flexure or from the absorption tests. Additionally, prepare
specimens by removing all loosely adhering particles, sand or
perature not exceeding 90°F [32°C].
edge shards from the surface or cores. Test five specimens.
9.1.2.2 Trays and Containers, shallow, metal, having an
1 1
9.2.2.2 Structural Clay Tile—The test specimens shall con-
inside depth of 1 ⁄2 6 ⁄2 in. [38 6 12.5 mm], and of suitable
sist of five tile or a partial tile with a minimum of 15 in. [110
strength and size so that the tray with a charge of frozen units
cm ] of finished face. Specimens damaged in the sawing
is movable by one technician.
process shall be discarded.
9.1.2.3 Thawing Tank of such dimensions as to permit
complete submersion of the specimens in their trays. Adequate
9.3 Procedure:
means shall be provided so that the water in the tank is kept at
9.3.1 Dry and cool the test specimens in accordance with
a temperature of 75 6 10°F [24 6 5.5°C].
5.1. Weigh and record the dry weight of each in accordance
9.1.3 Apparatus—Method B: with 5.2.
9.3.2 Carefully examine each specimen for cracks. A crack
9.1.3.1 The freezing-and-thawing apparatus shall consist of
is defined as a fissure or separation visible to a person with
a suitable chamber or chambers in which the specimens may be
normal vision from a distance of one foot under an illumination
subjected to the specified freezing-and-thawing cycle, together
of not less than 50 fc [540 lx]. Mark each crack its full length
with the necessary refrigerating and heating equipment and
with an indelible felt marking pen.
controls to produce continuously, and automatically, reproduc-
9.3.3 Freezing and Thawing Method A:
ible cycles within the specified temperature and time require-
ments. In the event that the equipment does not operate 9.3.3.1 Submerge the test specimens in the water of the
automatically, provision shall be made for either its continuous thawing tank for 4 6 ⁄2 h.
C67/C67M − 23a
9.3.3.2 Remove the specimens from the thawing tank and 9.3.3.6 After completion of 50 cycles, or when the test
stand them in the freezing trays with one of their head faces specimen has been withdrawn from test as a result of
down. Head face is defined as the end surfaces of a whole
disintegration, dry and weigh the specimen as prescribed in
rectangular brick (which have the smallest area). (See Note 7.)
9.3.1.
A space of at least ⁄2 in. [12.5 mm] shall separate the
9.3.4 Freezing and Thawing Method B:
specimens as placed in the tray. Pour sufficient water into the
9.3.4.1 A sample temperature measurement device meeting
trays so that each specimen stands in ⁄2 in. [12.5 mm] depth of
the requirements given in 9.1.3.3 is mounted in the control
water and then place the trays and their contents in the freezing
sample.
chamber for 20 6 1 h.
(1) If the samples are solid units, one horizontal hole of a
NOTE 7—The dimensions of some brick may prevent specimens from
slightly larger diameter than the temperature sensing device
standing without support on one of their head faces. In such a case, any
shall be drilled perpendicularly into the bed face of one of the
suitable rack or support that will achieve the ⁄2 in. [12.5 mm] separation
1 specimens per test pan. The hole shall be approximately ⁄4 in.
of specimens and the specimen standing in ⁄2 in. [12.5 mm] depth of water
will suffice. [19 mm] in from the finished stretcher face, and to a depth of
approximately one half of the specimen. An L-shaped thermo-
9.3.3.3 Remove the trays from the freezing chamber after
couple is inserted into this hole as the temperature sensor and
20 6 1 h and totally immerse them and their contents in the
can be secured in place with plumbers putty or similar material.
water of the thawing tank for 4 6 ⁄2 h.
(See Fig. 1.)
9.3.3.4 Freeze the test specimens by the procedure in 9.3.3.2
(2) If the sample has core holes, place the sample tempera-
one cycle each day of the normal work week. Following the
4 6 ⁄2 h thawing after the last freeze-thaw cycle of the normal ture L-shaped thermocouple in the bottom of the lowest core
work week, remove the specimens from the trays and store hole and check that the measurement end of the temperature
them for 44 6 1 h in the drying room. Do not stack or pile
measurement sensor is roughly equidistant from both bed faces
units. Provide a space of at least 1 in. [25 mm] between all
of one of the specimens per test pan. The temperature sensor
specimens. Following this period of air drying, inspect the
can be secured in place with dense polystyrene or similar
specimens, submerge them in the water of the thawing tank for
material pressed into the core hole, keeping the temperature
4 6 ⁄2 h, and again subject them to a normal week of freezing
sensor in contact with the surface of the core hole. (See Fig. 2.)
and thawing cycles in accordance with 9.3.3.2 and 9.3.3.3.
9.3.4.2 Submerge the dry, cooled specimens, without pre-
When a normal 5-day work week is interrupted, put specimens
liminary partial immersion, in clean water (soft, distilled or
into a drying cycle, which meets or extends past the 44 6 1 h
rain water) at 60 to 86°F [15.5 to 30°C] for a minimum of 24
drying time outlined in the procedures of this section.
hours.
9.3.3.5 Continue the alternations of drying and submersion
9.3.4.3 The five specimens are placed in the test pan(s) with
in water for 4 6 ⁄2 h, followed by 5 cycles of freezing and
the finished stretcher face oriented down. The specimen with
thawing or the number of cycles needed to complete a normal
the temperature measurement device should be located near the
work week, until a total of 50 cycles of freezing and thawing
center of the pan. The samples should be oriented so that they
has been completed. Stop the test when the test specimen
are spaced at least ⁄4 in. [6 mm] apart.
develops a crack as defined in 9.4.3, breaks, or appears to have
lost more than 3 % of its original weight by disintegration as 9.3.4.4 The pan is then filled and maintained with
judged by visual inspection. ⁄4 6 0.25 in. [19 6 6 mm] of water.
FIG. 1 Typical Configuration for Testing Solid Units
C67/C67M − 23a
FIG. 2 Typical Configuration for Testing Cored Units
9.3.4.5 The samples are placed in a freezer and cycled for extensions of previously marked cracks. Examine the speci-
50 freezing and thawing cycles in accordance with the require- mens for disintegration during the freeze-thaw process.
ments given in 9.3.4.5. 9.4.3 Rating—A specimen is considered to fail the freezing
(1) The nominal freezing-and-thawing cycle shall consist and thawing test under any of the following circumstances:
of alternately lowering the temperature of the specimens from 9.4.3.1 Breakage and Weight Loss—A separation or disin-
40 to 7°F [4 to –14°C] and raising it from 7 to 40°F [–14 to tegration resulting in a weight loss of greater than that
4°C]. The total time required to perform a complete freezing- permitted by the referenced unit specification for the appropri-
and-thawing cycle shall not be less than 2 h. ate classification.
(2) The cooling period is completed when the temperature 9.4.3.2 Cracking—A specimen develops a crack during the
at the centers of the specimens reach 7 6 3°F [–14 6 2°C], and freezing and thawing procedure that exceeds the length per-
the heating period is completed when the temperature reaches mitted by the referenced unit standard for the appropriate
40 6 3°F [4 6 2°C], with the temperature at the center of the classification. If none of the above circumstances occur, the
control specimen at no time reaching a temperature higher than specimens are considered to pass the freezing and thawing test.
68°F [20°C]. 9.4.4 Report—The report shall state whether the sample
(3) The time required for the temperature at the center of passed or failed the test. Any specimen that fails shall be
the control specimen to be reduced from 40 to 7°F [4 to –14°C] identified with a fail rating and the reason for classification as
shall be not less than 30 minutes, and the time required for the a failure. If Method A is being performed, the number of cycles
temperature at the center of the control specimen to be raised causing failure shall be reported in the event failure occurs
from 7 to 40°F [–14 to 4°C] shall be not less than 30 minutes. prior to 50 cycles.
(4) During cycling, the difference between the temperature
at the center of the control specimen and the temperature at its 10. Initial Rate of Absorption (Suction) (Laboratory Test)
surface shall at no time exceed 82°F [28°C].
10.1 Apparatus:
(5) During cycling, the temperature at the specimen surface
10.1.1 Trays or Containers—Watertight trays or containers,
shall at no time exceed 90°F [32°C].
having an inside depth of not less than ⁄2 in. [12.5 mm], and of
(6) When the sequence of freezing-and-thawing cycles 2
such length and width that an area of not less than 300 in.
must be interrupted, store the specimens in a frozen condition. 2
[2000 cm ] of water surface is provided. The bottom of the tray
9.3.5 After completion of 50 cycles, or when the test
shall provide a plane, horizontal upper surface, when suitably
specimen has been withdrawn from test as a result of
supported, so that an area not less than 8 in. [200 mm] in length
disintegration, dry and weigh the specimen as prescribed in
by 6 in. [150 mm] in width will be level when tested by a spirit
9.3.1.
level.
9.4 Calculations, Examination, Rating and Report: 10.1.2 Supports for Brick—Two noncorrodible metal sup-
9.4.1 Calculation—Calculate the loss in weight as a per- ports consisting of bars between 5 and 6 in. [125 and 150 mm]
centage of the original weight of the dried specimen. in length, having triangular, half-round, or rectangular cross
9.4.2 Examination—Re-examine the surface of the speci- sections such that the thickness (height) will be approximately
mens for cracks (see 9.3.2) and record the presence of any new ⁄4 in. [6 mm]. The thickness of the two bars shall agree within
cracks developed during the freezing-thawing testing proce- 0.001 in. [0.03 mm] and, when the bars are rectangular in cross
dure. Measure and record the length of the new cracks and any section, their width shall not exceed ⁄16 in. [8 mm].
C67/C67M − 23a
10.1.3 Means for Maintaining Constant Water Level— weighings at intervals of 2 h show an increment of loss not
Suitable means for controlling the water level above the upper greater than 0.2 % of the last previously determined weight of
surface of the supports for the brick within 60.01 in. [0.25 the specimen.
mm] (see Note 8), including means for adding water to the tray
10.3.2 Measure to the nearest 0.05 in. [1.25 mm] the length
at a rate corresponding to the rate of removal by the brick
and width of the flatwise surface of the test specimen of
undergoing test (see Note 9). For use in checking the adequacy
rectangular units or determine the area of other shapes to
of the method of controlling the rate of flow of the added water,
similar accuracy that will be in contact with the water. Weigh
a reference brick or half brick shall be provided whose
the specimen to the nearest 0.5 g.
displacement in ⁄8 in. [3 mm] of water corresponds to the brick
10.3.3 Adjust the position of the tray for the absorption test
or half brick to be tested within 62.5 %. Completely submerge
so that the upper surface of its bottom will be level when tested
the reference brick in water for not less than 3 h preceding its
by a spirit level, and set the saturated reference brick (10.1.3)
use.
in place on top of the supports. Add water until the water level
is ⁄8 6 0.01 in. [3.00 6 0.25 mm] above the top of the
NOTE 8—A suitable means for obtaining accuracy in control of the
supports. When testing tile with scored bed surfaces, the depth
water level is provided by attaching to the end of one of the bars two stiff
metal wires that project upward and return, terminating in points; one of
of water level is ⁄8 6 0.01 in. [3.00 6 0.25 mm] plus the depth
1 1
which is ⁄8 − 0.01 in. [3.00 – 0.25 mm] and the other ⁄8 + 0.01 in.
of scores.
[3.00 + 0.25 mm] above the upper surface or edge of the bar. Such precise
10.3.4 After removal of the reference brick, set the test brick
adjustment is obtainable by the use of depth plates or a micrometer
in place flatwise, counting zero time as the moment of contact
microscope. When the water level with respect to the upper surface or
edge of the bar is adjusted so that the lower point dimples the water
of the brick with the water. During the period of contact (1 min
surface when viewed by reflected light and the upper point is not in
6 1 s) keep the water level within the prescribed limits by
contact with the water, the water level is within the limits specified. Any
adding water as required. At the end of 1 min 6 1 s, lift the
other suitable means for fixing and maintaining a constant depth of
brick from contact with the water, wipe off the surface water
immersion shall be permitted when equivalent accuracy is obtained. An
with a damp cloth, and reweigh the brick to the nearest 0.5 g.
example of such other suitable means is the use of rigid supports movable
with respect to the water level.
Wiping shall be completed within 10 s of removal from contact
NOTE 9—A rubber tube leading from a siphon or gravity feed and
with the water, and weighing shall be completed within 2 min.
closed by a spring clip will provide a suitable manual control. The
so-called “chicken-feed” devices as a rule lack sensitivity and do not
NOTE 11—Place the brick in contact with the water quickly, but without
operate with the very small changes in water level permissible in this test.
splashing. Set the brick in position with a rocking motion to avoid the
entrapping of air on its under surface. Test brick with frogs or depressions
10.1.4 Balance, having a capacity of not less than 3000 g,
in one flatwise surface with the frog or depression uppermost. Test molded
and sensitive to 0.5 g.
brick with the struck face down.
10.1.5 Drying Oven, conforming to the requirements of
10.4 Calculation and Report:
9.1.1.2.
10.4.1 The difference in weight in grams between the initial
10.1.6 Timing Device—A suitable timing device, preferably
and final weighings is the weight in grams of water absorbed
a stop watch or stop clock, which shall indicate a time of 1 min
by the brick during 1-min contact with the water. When the
to the nearest 1 s.
area of its flatwise surface (length times width) does not differ
2 2 2 2
more than 60.75 in. [5 cm ] (62.5 %) from 30 in. [200 cm ],
10.2 Test Specimens, consisting of whole brick. Five speci-
report the gain in weight of each specimen to the nearest 0.1 g,
mens shall be tested.
as its initial rate of absorption in 1 min.
10.3 Procedure:
10.4.2 When the area of its flatwise surface differs more
10.3.1 The initial rate of absorption shall be determined for 2 2 2 2
than 6 0.75 in. [5 cm ] (62.5 %) from 30 in. [200 cm ],
the test specimen as specified, either oven-dried or ambient 2 2
calculate the equivalent gain in weight from 30 in. [200 cm ]
air-dried. When not specified, the initial rate of absorption shall
of each specimen to the nearest 0.1 g as follows:
be determined for the test specimens oven-dried. Dry and cool
X 5 30 W/LB metric X 5 200 W/LB (6)
~ !
the test specimens in accordance with the applicable proce-
dures 10.3.1.1 or 10.3.1.2. Complete the test procedure in
where:
accordance with 10.3.2, 10.3.3, and 10.3.4. 2 2
X = gain in weight corrected to basis of 30 in. [200 cm ]
flatwise area,
NOTE 10—There is no correlated relationship between the value of
W = actual gain in weight of specimen, g,
initial rate of absorption for ambient air-dried and oven-dried units. The
test methods provide different information. L = length of specimen, in., [cm], and
B = width of specimen, in., [cm].
10.3.1.1 Oven-dried Procedure—Dry and cool the test
specimens in accordance with 5.1. 10.4.3 Report the corrected gain in weight, X, of each
specimen to the nearest 0.1 g, as the initial rate of absorption
10.3.1.2 Ambient Air-dried Procedure—Store units
in 1 min.
unstacked, with separate placement in a ventilated room
maintained at a temperature of 75 6 15°F [24 6 8°C] with a 10.4.4 When the test specimen is a cored brick, calculate the
relative humidity between 30 % and 70 % for a period of 4 h, net area and substitute for LB in the equation given in 10.4.2.
with a current of air from an electric fan passing over them for Report the corrected gain in weight, X, of each specimen to the
a period of at least 2 hours. Continue until two successive nearest 0.1 g, as the initial rate of absorption in 1 min.
C67/C67M − 23a
10.4.5 When the specimen is non-prismatic, calculate the several specimens are tested in the same container, separate the
net area by suitable geometric means and substitute for LB in individual specimens by a spacing of at least 2 in. [50 mm].
the equation given in 10.4.2.
NOTE 13—Do not test specimens from different sources simultaneously
in the same container, because specimens with a considerable content of
10.5 Calculate and report the average initial rate of absorp-
soluble salts will contaminate salt-free specimens.
tion of all specimens tested to the nearest 0.1 g/min/30
2 2 NOTE 14—Empty and clean the pans or trays after each test.
in. [200 cm ].
11.4.2 Store the second specimen from each of the five pairs
10.6 Report the method of drying as oven-dried (in accor-
in the drying room without contact with water.
dance with 10.3.1.1) or ambient air-dried (in accordance with
11.4.3 At the end of 7 days, inspect the first set of specimens
10.3.1.2).
and then dry both sets using one of the two methods described
in 11.3.1 and 11.3.2.
11. Efflorescence
11.5 Examination and Rating—After drying, examine and
11.1 Apparatus:
compare each pair of specimens, observing the top and all four
11.1.1 Trays and Containers—Watertight shallow pans or
faces of each specimen from a distance of 10 ft [3 m] under an
trays made of corrosion-resistant metal or o
...