ASTM C1038/C1038M-24

Standard Test Method for Expansion of Hydraulic Cementitious Material Mortar Bars Stored in Water

SIGNIFICANCE AND USE
4.1 This test method is used to determine the amount of expansion of a mortar bar when it is stored in water. The amount of mortar-bar expansion may relate to the amount of sulfate in the cementitious material; expansion may become excessive when the cementitious material contains too much sulfate.  
4.2 Some cementitious material specifications limit the amount of sulfate contained in those materials by requiring that the amount of expansion in water not exceed a specified value.
SCOPE
1.1 This test method covers the determination of the expansion of mortar bars made using hydraulic cementitious materials, of which sulfate is an integral part.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.3 The text of this standard refers to notes and footnotes that provide explanatory material. These notes shall not be considered as requirements of the 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.2)  
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

• Status: Published
• Publication Date: 31-Mar-2024
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: C01 - Cement
• Drafting Committee: C01.28 - Sulfate Content

Relations

• Replaces: ASTM C1038/C1038M-19 - Standard Test Method for Expansion of Hydraulic Cement Mortar Bars Stored in Water
• Effective Date: 01-Apr-2024
• Refers: ASTM C219-24 - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Apr-2024
• Refers: ASTM C109/C109M-21 - Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50 mm] Cube Specimens)
• Effective Date: 15-Jul-2021
• Refers: ASTM C219-20a - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Aug-2020
• Referred By: ASTM C1157/C1157M-23 - Standard Performance Specification for Hydraulic Cement
• Effective Date: 01-Apr-2024
• Referred By: ASTM C1600/C1600M-23 - Standard Specification for Rapid Hardening Hydraulic Cement
• Effective Date: 01-Apr-2024
• Referred By: ASTM C595/C595M-23 - Standard Specification for Blended Hydraulic Cements
• Effective Date: 01-Apr-2024
• Referred By: ASTM C150/C150M-22 - Standard Specification for Portland Cement
• Effective Date: 01-Apr-2024
• Referred By: ASTM C183/C183M-23 - Standard Practice for Sampling and the Amount of Testing of Hydraulic Cement
• Effective Date: 01-Apr-2024
• Referred By: ASTM C989/C989M-24 - Standard Specification for Slag Cement for Use in Concrete and Mortars
• Effective Date: 01-Apr-2024

Overview

ASTM C1038/C1038M-24 is an internationally recognized standard test method developed by ASTM International for determining the expansion of mortar bars made from hydraulic cementitious materials stored in water. The primary focus of this standard is to assess the dimensional stability and volumetric expansion of cementitious mortar bars, which can be an important indicator of sulfate content in the cement. Excessive expansion often points to higher sulfate levels that can compromise the durability and performance of cement-based construction materials.

This test method is widely used in quality control and specification compliance within the cement, concrete, and construction industries. Its procedures provide critical data that help manufacturers and specifiers ensure that hydraulic cementitious materials meet certain performance requirements, especially regarding sulfate content.

Key Topics

• Expansion Measurement: The standard outlines the procedures for preparing and storing mortar bars and subsequently measuring their expansion after immersion in water at set intervals, most notably at the 14-day mark.
• Significance of Sulfate Content: The expansion of mortar bars in water is closely related to the sulfate content of hydraulic cementitious materials. High sulfate levels may lead to excessive expansion, affecting structural integrity.
• Test Specimen Preparation: Detailed guidance is provided for mixing, molding, and curing mortar bars, including requirements for dimensions, materials (such as graded sand and mixing water), and curing conditions.
• Units and Measurements: The test method specifies the use of both SI (metric) and inch-pound (imperial) units, which are to be used separately to ensure consistency and avoid non-conformance.
• Precision and Safety: The standard addresses the procedures for evaluating measurement precision and provides safety warnings due to the caustic nature of fresh hydraulic cement mixes.

Applications

ASTM C1038/C1038M is essential for:

• Cement Manufacturers: Assuring product compliance by limiting the sulfate content of hydraulic cement through expansion testing.
• Concrete Producers: Evaluating the suitability of cementitious materials for use in concrete mixes to ensure long-term durability and reduced risk of expansion-induced cracking.
• Specifiers and Regulators: Using expansion data as part of quality control to enforce limits on sulfate levels in cementitious materials as required by regional or international specifications.
• Research and Development: Investigating the performance characteristics of new or modified cement formulations under water storage conditions.

This test method is applicable to portland cement, blended cements, and other hydraulic cementitious materials where sulfate content and stability are critical factors affecting performance over time.

Related Standards

ASTM C1038/C1038M-24 references or is associated with several other ASTM standards, including:

• ASTM C109/C109M: Test Method for Compressive Strength of Hydraulic Cement Mortars
• ASTM C114: Test Methods for Chemical Analysis of Hydraulic Cement
• ASTM C125: Terminology Relating to Concrete and Concrete Aggregates
• ASTM C219: Terminology Relating to Hydraulic and Other Inorganic Cements
• ASTM C305: Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars
• ASTM C490: Practice for Use of Apparatus for the Determination of Length Change
• ASTM C511: Specification for Mixing Rooms and Water Storage Tanks for Testing
• ASTM C778: Specification for Standard Sand
• ASTM C1005: Specification for Reference Masses and Devices for Determining Mass and Volume
• ASTM C1437: Test Method for Flow of Hydraulic Cement Mortar

Practical Value

Compliance with ASTM C1038/C1038M-24 helps ensure that hydraulic cementitious materials will perform reliably and resist undesirable expansion due to excess sulfates when used in concrete construction. Adhering to this test method protects stakeholders throughout the supply chain from the risks associated with unsound or unstable materials, ultimately enhancing the quality and longevity of concrete structures.

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: C1038/C1038M − 24
Standard Test Method for
Expansion of Hydraulic Cementitious Material Mortar Bars
Stored in Water
This standard is issued under the fixed designation C1038/C1038M; 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* Hydraulic Cement Mortars (Using 50 mm [2 in.] Cube
Specimens)
1.1 This test method covers the determination of the expan-
C114 Test Methods for Chemical Analysis of Hydraulic
sion of mortar bars made using hydraulic cementitious
Cement
materials, of which sulfate is an integral part.
C125 Terminology Relating to Concrete and Concrete Ag-
1.2 The values stated in either SI units or inch-pound units
gregates
are to be regarded separately as standard. The values stated in
C219 Terminology Relating to Hydraulic and Other Inor-
each system may not be exact equivalents; therefore, each
ganic Cements
system shall be used independently of the other. Combining
C305 Practice for Mechanical Mixing of Hydraulic Cement
values from the two systems may result in non-conformance
Pastes and Mortars of Plastic Consistency
with the standard.
C490 Practice for Use of Apparatus for the Determination of
Length Change of Hardened Cement Paste, Mortar, and
1.3 The text of this standard refers to notes and footnotes
that provide explanatory material. These notes shall not be Concrete
C511 Specification for Mixing Rooms, Moist Cabinets,
considered as requirements of the standard.
Moist Rooms, and Water Storage Tanks Used in the
1.4 This standard does not purport to address all of the
Testing of Hydraulic Cements and Concretes
safety concerns, if any, associated with its use. It is the
C778 Specification for Standard Sand
responsibility of the user of this standard to establish appro-
C1005 Specification for Reference Masses and Devices for
priate safety, health, and environmental practices and deter-
Determining Mass and Volume for Use in Physical Testing
mine the applicability of regulatory limitations prior to use.
of Hydraulic Cements
(Warning—Fresh hydraulic cementitious mixtures are caustic
C1437 Test Method for Flow of Hydraulic Cement Mortar
and may cause chemical burns to skin and tissue upon
prolonged exposure. )
3. Terminology
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
3.1 Definitions:
ization established in the Decision on Principles for the
3.1.1 See Terminology C219 and Terminology C125.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4. Significance and Use
Barriers to Trade (TBT) Committee.
4.1 This test method is used to determine the amount of
expansion of a mortar bar when it is stored in water. The
2. Referenced Documents
amount of mortar-bar expansion may relate to the amount of
2.1 ASTM Standards:
sulfate in the cementitious material; expansion may become
C109/C109M Test Method for Compressive Strength of
excessive when the cementitious material contains too much
sulfate.
This test method is under the jurisdiction of ASTM Committee C01 on Cement
4.2 Some cementitious material specifications limit the
and is the direct responsibility of Subcommittee C01.28 on Sulfate Content.
amount of sulfate contained in those materials by requiring that
Current edition approved April 1, 2024. Published April 2024. Originally
approved in 1985. Last previous edition approved in 2019 as C1038/C1038M – 19. the amount of expansion in water not exceed a specified value.
DOI: 10.1520/C1038_C1038M-24.
Section on Safety, Manual of Cement Testing, Annual Book of Standards,
5. Apparatus
Vol. 04.01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.1 Reference Masses and Mass-Determining Devices, con-
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
forming to the requirements of Specification C1005. Evaluate
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. the device for precision and bias at a total load of 2 kg.
*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
C1038/C1038M − 24
5.2 Glass Graduates, Molds, and Length Comparator, con- 8.3.2 Mix the mortar in accordance with the procedure
forming to the requirements of Specification C490. described in Practice C305.
8.4 Molding Test Specimens—Immediately upon comple-
5.3 Moist Cabinet or Room, conforming to the requirements
of Specification C511. tion of mixing, remove the paddle and the bowl from the mixer
and shake the excess mortar from the paddle into the bowl. Fill
5.4 Mixer, Bowl, and Paddle, conforming to the require-
the mold in two layers, compacting each layer with the tamper.
ments of Practice C305.
Work the mortar into the corners, around the gauge studs, and
5.5 Trowel and Tamper, conforming to the requirements of
along the surfaces of the mold with the tamper until a
Test Method C109/C109M.
homogeneous specimen is obtained. After the top layer has
been compacted, cut the mortar off flush with the top of the
6. Temperature and Relative Humidity
mold and smooth the surface with a few strokes of the trowel.
6.1 Molding Room, Dry Materials, and Mixing Water—
9. Storage of Test Specimens
Maintain the temperature of the molding room, dry materials,
9.1 Initial Storage—Immediately upon completion of
and mixing water at 23.0 °C 6 4.0 °C [73.5 °F 6 7.0 °F], and
molding, place the test specimens in the moist cabinet or moist
maintain the relative humidity of the molding room at not less
room. Keep all test specimens in the molds in the moist cabinet
than 50 %.
or moist room for 22.5 h 6 0.5 h with upper surfaces exposed
to the moist air but protected from dripping water. After this
7. Reagents and Materials
time, remove the specimens from the molds, properly identify,
7.1 Mixing Water—Potable water is satisfactory for routine
and place in water or saturate
...

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.
Designation: C1038/C1038M − 19 C1038/C1038M − 24
Standard Test Method for
Expansion of Hydraulic Cement Cementitious Material
Mortar Bars Stored in Water
This standard is issued under the fixed designation C1038/C1038M; 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 covers the determination of the expansion of mortar bars made using hydraulic cement, cementitious
materials, of which sulfate is an integral part.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.3 The text of this standard refers to notes and footnotes that provide explanatory material. These notes shall not be considered
as requirements of the 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 appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns
to skin and tissue upon prolonged exposure. )
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.
2. Referenced Documents
2.1 ASTM Standards:
C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 50 mm [2 in.] Cube Specimens)
C114 Test Methods for Chemical Analysis of Hydraulic Cement
C125 Terminology Relating to Concrete and Concrete Aggregates
C219 Terminology Relating to Hydraulic and Other Inorganic Cements
C305 Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic Consistency
C490 Practice for Use of Apparatus for the Determination of Length Change of Hardened Cement Paste, Mortar, and Concrete
C511 Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic
Cements and Concretes
C778 Specification for Standard Sand
This test method is under the jurisdiction of ASTM Committee C01 on Cement and is the direct responsibility of Subcommittee C01.28 on Sulfate Content.
Current edition approved Dec. 15, 2019April 1, 2024. Published January 2020April 2024. Originally approved in 1985. Last previous edition approved in 20142019 as
C1038/C1038M – 14b.C1038/C1038M – 19. DOI: 10.1520/C1038_C1038M-19.10.1520/C1038_C1038M-24.
Section on Safety, Manual of Cement Testing, Annual Book of Standards, Vol. 04.01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on 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
C1038/C1038M − 24
C1005 Specification for Reference Masses and Devices for Determining Mass and Volume for Use in Physical Testing of
Hydraulic Cements
C1437 Test Method for Flow of Hydraulic Cement Mortar
3. Terminology
3.1 Definitions:
3.1.1 See Terminology C219 and Terminology C125.
4. Significance and Use
4.1 This test method is used to determine the amount of expansion of a mortar bar when it is stored in water. The amount of
mortar-bar expansion may relate to the amount of sulfate in the cement; cementitious material; expansion may become excessive
when the cement cementitious material contains too much sulfate.
4.2 Some cement cementitious material specifications limit the amount of sulfate contained in hydraulic cementthose materials by
requiring that the amount of expansion in water not exceed a specified value.
5. Apparatus
5.1 Reference Masses and Mass-Determining Devices, conforming to the requirements of Specification C1005. Evaluate the
device for precision and bias at a total load of 2 kg.
5.2 Glass Graduates, Molds, and Length Comparator, conforming to the requirements of Specification C490.
5.3 Moist Cabinet or Room, conforming to the requirements of Specification C511.
5.4 Mixer, Bowl, and Paddle, conforming to the requirements of Practice C305.
5.5 Trowel and Tamper, conforming to the requirements of Test Method C109/C109M.
6. Temperature and Relative Humidity
6.1 Molding Room, Dry Materials, and Mixing Water—Maintain the temperature of the molding room, dry materials, and mixing
water at 23.023.0 °C 6 4.0 °C [73.5[73.5 °F 6 7.0 °F], and maintain the relative humidity of the molding room at not less than
50 %.
7. Reagents and Materials
7.1 Mixing Water—Potable water is satisfactory for routine tests. For all cooperative tests and in case of dispute, use reagent water
as defined in Test Methods C114.
7.2 Graded Sand—Sand for making the test specimens shall conform to the requirements for graded standard sand in Specification
C778.
8. Procedure
8.1 Number and Dimensions of Test Specimens—Make four 25 by 25 by 285-mm [1 by 1 by 11 ⁄4-in.] test specimens for each
cement. The effective gauge length of these specimens is 250 mm [10 in.].cementitious material.
NOTE 1—In routine tests, 25 by 25 by 160-mm [1 by 1 by 6 ⁄4-in.] specimens may be used; however, in case of dispute, results obtained with 25 by 25
by 285-mm [1 by 1 by 11 ⁄4-in.] specimens shall govern. The effective gauge length of this specimen is 125 mm [5 in.].
8.1.1 The dimensions of the test specimens shall be 25 mm by 25 mm by 285 mm [1 in. by 1 in. by 11 ⁄4 in.] or 25 mm by 25 mm
by 160 mm [1 in. by 1 in. by 6 ⁄4 in.]. In case of dispute, results obtained with 25 mm by 25 mm by 285 mm [1 in. by 1 in. by
11 ⁄4 in.] specimens shall govern.
C1038/C1038M − 24
8.2 Specimen Molds—Prepare the specimen molds in accordance with the requirements of Specification C490, except cover the
interior surfaces of the mold with a release agent. A release agent will be acceptable if i
...