ASTM C928/C928M-20a

Standard Specification for Packaged, Dry, Rapid-Hardening Cementitious Materials for Concrete Repairs

ABSTRACT
This specification covers packaged, dry, cementitious mortar or concrete materials for rapid repairs to hardened hydraulic-cement concrete pavements and structures. Materials that contain organic compounds, such as bitumens, epoxy resins, and polyesters, as the principal binder are not included. Packaged, dry, concrete material contains aggregate of which at least 5% by mass of the total mixture is retained. Packaged, dry, mortar material contains aggregate of which less than 5% by mass of the total mixture is retained. Aqueous solutions, aqueous emulsions or dispersions may be included as components of the packaged materials. Aggregates must be included as a component of the packaged materials. Both packaged dry concrete and mortar shall be mechanically mixed with the use of a mixing liquid. Different test methods shall be performed in order to determine the following properties: compressive strength, length change, scaling resistance, and slant shear bond strength.
SCOPE
1.1 This specification covers packaged, dry, cementitious mortar or concrete materials for rapid repairs to hardened hydraulic-cement concrete pavements and structures. Materials that contain organic compounds, such as bitumens, epoxy resins, and polymers, as the principal binder are not included.  
1.1.1 Packaged, dry, concrete material contains aggregate of which at least 5 % by mass of the total mixture is retained on a 9.5-mm [3/8-in.] sieve.  
1.1.2 Packaged, dry, mortar material contains aggregate of which less than 5 % by mass of the total mixture is retained on a 9.5-mm [3/8-in.] sieve.  
1.2 Aqueous solutions, aqueous emulsions or dispersions may be included as components of the packaged materials. The manufacturer may specify that these liquids are to replace some or all of the mixing water.  
1.3 Aggregates must be included as a component of the packaged materials. The manufacturer may recommend job site addition of specific amounts and types of additional aggregates to his product for some uses. However, such reformulated products are not within the scope of this specification.  
1.4 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.  
1.5 The following safety hazards caveat pertains to the test methods portion of this specification:  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.  
1.6 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-Aug-2020
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: C09 - Concrete and Concrete Aggregates
• Drafting Committee: C09.43 - Packaged Dry Combined Materials

Relations

• Refers: ASTM E96/E96M-24 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 01-Mar-2024
• Refers: ASTM C670-24a - Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
• Effective Date: 01-Feb-2024
• Refers: ASTM C670-24 - Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM C109/C109M-23 - Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 50 mm [2 in.] Cube Specimens)
• Effective Date: 15-Dec-2023
• Refers: ASTM C39/C39M-23 - Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
• Effective Date: 01-Dec-2023
• Refers: ASTM E96/E96M-23 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 15-Nov-2023
• Refers: ASTM C125-19a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 15-Dec-2019
• Refers: ASTM C125-19 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jan-2019
• Refers: ASTM C125-18b - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Oct-2018
• Refers: ASTM C125-18a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jul-2018
• Refers: ASTM C125-18 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 01-Jan-2018
• Refers: ASTM C157/C157M-17 - Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete
• Effective Date: 15-Aug-2017
• Refers: ASTM C39/C39M-17b - Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
• Effective Date: 01-Aug-2017
• Refers: ASTM C125-16 - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 15-Dec-2016
• Refers: ASTM C39/C39M-16b - Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
• Effective Date: 01-Aug-2016

Overview

ASTM C928/C928M-20a is the internationally recognized standard specification developed by ASTM International for packaged, dry, rapid-hardening cementitious materials used in concrete repairs. This standard specifies requirements for materials supplied as dry mortars or concrete, designed specifically for rapid repairs of hardened hydraulic-cement concrete pavements and structures. The primary purpose of the standard is to ensure that repair materials deliver consistent performance, durability, and suitability for quick restoration of concrete surfaces.

This specification excludes materials using organic binders, such as bitumens, epoxies, and polyesters, focusing solely on cement-based systems. Both packaged mortar and packaged concrete falling under this standard must contain aggregate and may include aqueous solutions or dispersions. The scope ensures that materials provide the necessary mechanical mixing performance, compressive strength, bond strength, and resistance to environmental challenges.

---

Key Topics

• Material Types: Covers both packaged, dry concrete and mortar, distinguished by the proportion of aggregate retained on a 9.5-mm sieve.
  • Concrete: ≥5% retained aggregate by mass.
  • Mortar: <5% retained aggregate by mass.
• Material Components: Requires inclusion of aggregates and may include aqueous ingredients as specified by the manufacturer.
• Performance Evaluation: Stipulates properties such as compressive strength, bond strength, length change (shrinkage/expansion), and scaling resistance.
• Test Methods: Refers to established ASTM test methods for verifying physical and mechanical properties, including compressive strength (C39/C39M, C109/C109M), bond strength (C882), and scaling resistance (C672/C672M).
• Packaging and Labeling: Defines requirements for net mass, water vapor transmission of packaging materials, and clear labeling for compliance and traceability.
• Safety and Compliance: Outlines the user's responsibility to implement appropriate safety, health, and environmental practices, and adhere to all applicable regulations.

---

Applications

ASTM C928/C928M-20a is widely utilized in the construction and maintenance of transportation infrastructure, industrial floors, and commercial or municipal structures requiring rapid repair to concrete surfaces. Common applications include:

• Roadway and runway repair: Quickly restores traffic pavements, airfields, and bridge decks, minimizing downtime and disruption.
• Repair of industrial slabs and loading docks: Enables fast turnaround in operational environments where extended closure is not feasible.
• Structural restoration: Supports urgent repairs in parking structures, tunnels, and water infrastructure where durability and compatibility with existing concrete are critical.
• Weather-critical environments: Ensures repairs are resilient against freeze-thaw cycles, deicing agents, and moisture ingress.

Contractors, civil engineers, and maintenance crews rely on this standard to select rapid-hardening repair products that meet stringent service requirements for strength development, dimensional stability, and resistance to harsh service conditions.

---

Related Standards

When working with cementitious repair materials for concrete, consider these related ASTM standards for comprehensive quality assurance:

• ASTM C39/C39M: Test Method for Compressive Strength of Cylindrical Concrete Specimens
• ASTM C109/C109M: Test Method for Compressive Strength of Hydraulic Cement Mortars
• ASTM C143/C143M: Test Method for Slump of Hydraulic-Cement Concrete
• ASTM C157/C157M: Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete
• ASTM C672/C672M: Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals
• ASTM C882: Test Method for Bond Strength of Epoxy-Resin Systems Used With Concrete by Slant Shear

These referenced standards ensure the consistency, reliability, and safety of fast-track concrete repair operations, supporting robust long-term performance in demanding environments.

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:C928/C928M −20a
Standard Specification for
Packaged, Dry, Rapid-Hardening Cementitious Materials for
Concrete Repairs
This standard is issued under the fixed designation C928/C928M; 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* 1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This specification covers packaged, dry, cementitious
ization established in the Decision on Principles for the
mortar or concrete materials for rapid repairs to hardened
Development of International Standards, Guides and Recom-
hydraulic-cement concrete pavements and structures. Materials
mendations issued by the World Trade Organization Technical
that contain organic compounds, such as bitumens, epoxy
Barriers to Trade (TBT) Committee.
resins, and polymers, as the principal binder are not included.
1.1.1 Packaged, dry, concrete material contains aggregate of
2. Referenced Documents
which at least5%by mass of the total mixture is retained on
a 9.5-mm [ ⁄8-in.] sieve. 2.1 ASTM Standards:
1.1.2 Packaged, dry, mortar material contains aggregate of C39/C39M Test Method for Compressive Strength of Cylin-
which less than5%by mass of the total mixture is retained on drical Concrete Specimens
a 9.5-mm [ ⁄8-in.] sieve. C78 Test Method for Flexural Strength of Concrete (Using
Simple Beam with Third-Point Loading)
1.2 Aqueous solutions, aqueous emulsions or dispersions
C109/C109M Test Method for Compressive Strength of
may be included as components of the packaged materials.The
Hydraulic Cement Mortars (Using 2-in. or [50 mm] Cube
manufacturermayspecifythattheseliquidsaretoreplacesome
Specimens)
or all of the mixing water.
C125 Terminology Relating to Concrete and Concrete Ag-
1.3 Aggregates must be included as a component of the
gregates
packaged materials. The manufacturer may recommend job
C143/C143M Test Method for Slump of Hydraulic-Cement
site addition of specific amounts and types of additional
Concrete
aggregates to his product for some uses. However, such
C157/C157M Test Method for Length Change of Hardened
reformulated products are not within the scope of this specifi-
Hydraulic-Cement Mortar and Concrete
cation.
C192/C192M Practice for Making and Curing Concrete Test
1.4 The values stated in either SI units or inch-pound units Specimens in the Laboratory
C403/C403M Test Method for Time of Setting of Concrete
are to be regarded separately as standard. The values stated in
each system may not be exact equivalents; therefore, each Mixtures by Penetration Resistance
C490/C490M Practice for Use of Apparatus for the Deter-
system shall be used independently of the other. Combining
values from the two systems may result in non-conformance mination of Length Change of Hardened Cement Paste,
Mortar, and Concrete
with the standard.
C494/C494M Specification for Chemical Admixtures for
1.5 The following safety hazards caveat pertains to the test
Concrete
methods portion of this specification: This standard does not
C666/C666M Test Method for Resistance of Concrete to
purport to address all of the safety concerns, if any, associated
Rapid Freezing and Thawing
with its use. It is the responsibility of the user of this standard
C670 Practice for Preparing Precision and Bias Statements
to establish appropriate safety, health, and environmental
for Test Methods for Construction Materials
practices and determine the applicability of regulatory limita-
C672/C672M Test Method for Scaling Resistance of Con-
tions prior to use.
crete Surfaces Exposed to Deicing Chemicals
This specification is under the jurisdiction of ASTM Committee C09 on
Concrete and ConcreteAggregates and is the direct responsibility of Subcommittee
C09.43 on Packaged Dry Combined Materials. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Sept. 1, 2020. Published October 2020. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1980. Last previous edition approved in 2020 as C928/C928M – 20. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/C0928_C0928M-20A. 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
C928/C928M−20a
C702 PracticeforReducingSamplesofAggregatetoTesting 5.1.1 Consider a total chloride ion content (Berman,
3,4
Size 1972) in the packaged repair material greater than 600
3 3
C778 Specification for Standard Sand
g/m [1 lb/yd ] of the hardened repair material indicative that
C882 Test Method for Bond Strength of Epoxy-Resin Sys-
the packaged material contains sufficient chlorides to cause
tems Used With Concrete By Slant Shear
corrosion to steel reinforcement when the concrete is exposed
C1012 Test Method for Length Change of Hydraulic-
to weather, is on the ground, or is in an otherwise moist
Cement Mortars Exposed to a Sulfate Solution
environment. A much lower chloride ion content is suggested
E96/E96M Test Methods for Water Vapor Transmission of
for use in prestressed concrete. Guidance for such users is
Materials
outside the scope of this specification.
3. Terminology
5.2 If the material contains metallic iron in excess of 1 % by
weight, the package markings shall contain the following
3.1 Definitions—For definitions of terms used in this speci-
statement in letter size no smaller than the directions for use:
fication refer to Terminology C125.
If small or scattered spots of iron-staining are considered objec-
4. Materials and Manufacture tionable, do not use this material where it will be exposed.
4.1 Three types of packaged, dry, rapid-hardening concrete
6. Performance Requirements
and three types of packaged, dry, rapid-hardening mortar are
identified in Table 1.
6.1 The materials shall comply with the performance re-
quirements in Table 1 for the applicable type.
5. Chemical Composition
5.1 If the material contains soluble chlorides or other
ingredients in sufficient quantity to cause corrosion to steel
Berman, H.A., Determination of Chloride in Hardened Portland Cement Paste,
reinforcement, the package markings shall contain the follow-
Mortar, and Concrete, ASTM Journal of Materials, Vol. 7 , No. 3, pp. 330–335,
ing statement in letter size no smaller than the directions for 1972.
Clear, K. C., and Harrigan, E. T., “Sampling and Testing for Chloride Ion in
use:
Concrete,” Report No. FHWA-RD77-85, Federal Highway Administration,
This material is not recommended for use in a moist environment in contact
Washington, DC, August 1977 (Available as PB 275–428/AS National Technical
with steel reinforcement.
Information Services).
A
TABLE 1 Performance Requirements
3 h 1 day 7 days 28 days
Compressive Strength, min, MPa [psi]
B
R1 concrete or mortar 3.5 [500] 14 [2000] 28 [4000]
B
R2 concrete or mortar 7.0 [1000] 21 [3000] 28 [4000]
B
R3 concrete or mortar 21 [3000] 35 [5000] 35 [5000]
Bond strength, min, MPa [psi]
R1, R2, and R3 concrete or mortar — 7 [1000] 10 [1500] —
Length change, based on length at 3 h, max, %
allowable increase after 28 days in water +0.15
R1, R2, and R3 concrete or mortar
allowable decrease after 28 days in air –0.15
C
Consistency of concrete or mortar concrete slump, Flow of mortar,
min, mm [in.] min, %
R1 consistency after 15 min after addition of mixing liquid 75 [3] 100
R2 and R3 consistency at 5 min after addition of mixing liquid 75 [3] 100
Scaling resistance to deicing chemicals after 25 cycles of freezing and thawing
Concrete, max visual rating 2.5
D 2 2
Mortar, max scaled material 5 kg/m [1 lb/ft ]
A
It is recognized that other characteristics of rapid-hardening concrete repair materials might need consideration. Such characteristics might be necessary in some
environments and applications; however, to impose specification limits on all products is considered beyond the scope of this specification. Optional considerations with
suggested methods of test may include tests for the following:
Time of setting Test Method C403/C403M
Flexural strength Test Method C78
Freeze thaw Test Method C666/C666M, Procedure A
Sulfate expansion Test Method C1012
B
The strength at 28 days shall be not less than the strength at 7 days.
C
Slump or flow requirements are waived for materials intended for vertical or overhead applications.
D 2 2
A 250-mm [10-in.] square spalled to an average depth of 3 mm [ ⁄8 in.] for 100 % of its surface would have about 10 kg/m [2.0 lb/ft ] of scaled material.
C928/C928M−20a
7. Sampling material can be mixed and applied at temperatures that lie
beyond the range of 20 6 8 °C [70 6 15 °F], the product must
7.1 A lot is the quantity of packaged repair material nor-
meet the requirements of Table 1. Specimens must be made
mally placed on a pallet. In general, this quantity will weigh
and cured in accordance with the procedures of this section.
from 900 to 1800 kg [2000 to 4000 lb].
The mixing, molding and curing temperatures during the first 3
7.2 A unit sample is a single package of material randomly
h after molding shall be within 61°C[62 °F] of the extreme
selected from the lot.
temperature(s) stated by the manufacturer in the package
markings.
8. Specimen Preparation
9. Test Methods
8.1 Concrete—Mechanically mix the packaged dry concrete
material with mixing liquid. Determine the properties of the
9.1 Manifestly Faulty Specimens—Treat manifestly faulty
unhardened mixture, and mold and cure the specimens in specimens in accordance with the corresponding section in
accordance with Practice C192/C192M or modifications as
Specification C494/C494M.
outlined herein.
9.2 Compressive Strength—Prepare and test three test speci-
8.1.1 The sample of packaged dry material shall be any
mensforeachageoftestandeachlevelofmixingtemperature.
combination of whole packages yielding not less than 20 L[ ⁄3
Test in accordance with Test Method C39/C39M for concrete
ft ] of hardened material.
and Test Method C109/C109M for mortar.
8.1.2 Base the quantity of water, other liquid component, or
9.3 Length Change—Prepare and test three specimens (set)
both added to the sample on the quantity per bag stated in the
in accordance with Test Method C157/C157M, except as
directions for use.
modified by this section and 8.3. The molds for casting test
8.1.3 Place the sample in the mixing machine and add the
specimens and the length comparator shall comply with the
required amount of liquid. Start mixing immediately. Continue
requirements of Practice C490/C490M.
mixingforthelengthoftimeindicatedinthedirectionsforuse.
9.3.1 Preparation of Specimen Molds and Material
8.1.4 When making the slump test in accordance with Test
Conditioning—The temperature of the mixing water and the
Method C143/C143M, schedule work so the test will be
materials used to prepare the test specimens shall be 23 6 2.0
completed in 5 6 ⁄2 min after the mixing liquid is added to the
1 °C [73.5 6 3.5 °F] except as modified by 8.3. The air
R2 or R3 materials or 15 6 ⁄2 min after mixing the liquid with
temperatureofthemixingroom,moldsandbaseplatesshallbe
the R1 materials.
maintained at 23 6 2.0 °C [73.5 6 3.5 °F] and at a relative
8.1.5 Mold the required number of specimens using addi-
humidity of not less than 50 % except if modified by 8.3.
tional samples as may be necessary, mixed in accordance with
Prepare the specimen molds in accordance with the require-
8.1.1 – 8.1.4. Do not use the mixtures for molding test
ments of Practice C490/C490M. Mold dimensions shall be at
specimens when the slump is less than that specified in Table
least three times the nominal aggregate size. The test specimen
1.
for mortar shall be a prism of 25-mm [1-in.] square cross-
NOTE 1—Where the nominal maximum particle size is not greater than
section and approximately 285-mm [11 ⁄4-in.] in length. The
25 mm [1 in.], the use of cylindrical molds 100 mm [4 in.] in diameter by
test specimen for concrete, which all the aggregate passes a
200 mm [8 in.] in length is suggested.
50-mm [2-in.] sieve, shall be a prism of 100-mm [4-in.] square
8.2 Mortar—Mechanically mix packaged dry mortar mate-
cross-section and approximately 285-mm [11 ⁄4-in.] long.
rial with mixing liquid. Determine the properties of the
However, a prism of 75-mm [3-in.] square cross-section shall
unhardened mixture, and mold and cure the specimens in
be used if all the aggregate passes a 25-mm [1-in.] sieve and a
accordancewithTestMethodC109/C109Mormodificationsas
50-mm [2-in.] square cross-section shall be used if all aggre-
outlined herein.
gates passes a 13-mm [ ⁄2-in.] sieve.
8.2.1 Thesampleofpackageddrymaterialshallweigh3000
9.3.2 Initial Curing and Demolding of Test Specimens—
6 3 g [6.6 6 0.005 lb] and shall be representatively obtained
Cure the test specimens in the molds at 23 6 2.0 °C [73.5 6
from a whole package in accordance with Practice C702.
3.5 °F] and not less than 50 % relative humidity except if
8.2.2 Base the quantity of water, or other liquid component,
modified by 8.3. Remove specimens from the m
...

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: C928/C928M − 20 C928/C928M − 20a
Standard Specification for
Packaged, Dry, Rapid-Hardening Cementitious Materials for
Concrete Repairs
This standard is issued under the fixed designation C928/C928M; 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 specification covers packaged, dry, cementitious mortar or concrete materials for rapid repairs to hardened hydraulic-
cement concrete pavements and structures. Materials that contain organic compounds, such as bitumens, epoxy resins, and
polymers, as the principal binder are not included.
1.1.1 Packaged, dry, concrete material contains aggregate of which at least 5 % by mass of the total mixture is retained on a
9.5-mm [ ⁄8-in.] sieve.
1.1.2 Packaged, dry, mortar material contains aggregate of which less than 5 % by mass of the total mixture is retained on a
9.5-mm [ ⁄8-in.] sieve.
1.2 Aqueous solutions, aqueous emulsions or dispersions may be included as components of the packaged materials. The
manufacturer may specify that these liquids are to replace some or all of the mixing water.
1.3 Aggregates must be included as a component of the packaged materials. The manufacturer may recommend job site addition
of specific amounts and types of additional aggregates to his product for some uses. However, such reformulated products are not
within the scope of this specification.
1.4 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.
1.5 The following safety hazards caveat pertains to the test methods portion of this specification: 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.
1.6 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.
This specification is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.43 on
Packaged Dry Combined Materials.
Current edition approved Jan. 1, 2020Sept. 1, 2020. Published January 2020October 2020. Originally approved in 1980. Last previous edition approved in 20192020 as
C928/C928M – 19.C928/C928M – 20. DOI: 10.1520/C0928_C0928M-20.10.1520/C0928_C0928M-20A.
*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
C928/C928M − 20a
2. Referenced Documents
2.1 ASTM Standards:
C39/C39M Test Method for Compressive Strength of Cylindrical Concrete Specimens
C78 Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading)
C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50 mm] Cube Specimens)
C125 Terminology Relating to Concrete and Concrete Aggregates
C143/C143M Test Method for Slump of Hydraulic-Cement Concrete
C157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete
C192/C192M Practice for Making and Curing Concrete Test Specimens in the Laboratory
C403/C403M Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance
C490/C490M Practice for Use of Apparatus for the Determination of Length Change of Hardened Cement Paste, Mortar, and
Concrete
C494/C494M Specification for Chemical Admixtures for Concrete
C666/C666M Test Method for Resistance of Concrete to Rapid Freezing and Thawing
C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
C672/C672M Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals
C702 Practice for Reducing Samples of Aggregate to Testing Size
C778 Specification for Standard Sand
C882 Test Method for Bond Strength of Epoxy-Resin Systems Used With Concrete By Slant Shear
C1012 Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution
E96/E96M Test Methods for Water Vapor Transmission of Materials
3. Terminology
3.1 Definitions—For definitions of terms used in this specification refer to Terminology C125.
4. Materials and Manufacture
4.1 Three types of packaged, dry, rapid-hardening concrete and three types of packaged, dry, rapid-hardening mortar are identified
in Table 1.
5. Chemical Composition
5.1 If the material contains soluble chlorides or other ingredients in sufficient quantity to cause corrosion to steel reinforcement,
the package markings shall contain the following statement in letter size no smaller than the directions for use:
This material is not recommended for use in a moist environment in contact
with steel reinforcement.
3,4 3 3
5.1.1 Consider a total chloride ion content (Berman, 1972) in the packaged repair material greater than 600 g/m [1 lb/yd ] of
the hardened repair material indicative that the packaged material contains sufficient chlorides to cause corrosion to steel
reinforcement when the concrete is exposed to weather, is on the ground, or is in an otherwise moist environment. A much lower
chloride ion content is suggested for use in prestressed concrete. Guidance for such users is outside the scope of this specification.
5.2 If the material contains metallic iron in excess of 1 % by weight, the package markings shall contain the following statement
in letter size no smaller than the directions for use:
If small or scattered spots of iron-staining are considered objec-
tionable, do not use this material where it will be exposed.
6. Performance Requirements
6.1 The materials shall comply with the performance requirements in Table 1 for the applicable type.
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.
Berman, H. A., Determination of Chloride in Hardened Portland Cement Paste, Mortar, and Concrete, ASTM Journal of Materials, Vol. 7 , No. 3, pp. 330–335, 1972.
Clear, K. C., and Harrigan, E. T., “Sampling and Testing for Chloride Ion in Concrete,” Report No. FHWA-RD77-85, Federal Highway Administration, Washington, DC,
August 1977 (Available as PB 275–428/AS National Technical Information Services).
C928/C928M − 20a
A
TABLE 1 Performance Requirements
3 h 1 day 7 days 28 days
Compressive Strength,
min, MPa [psi]
B
3.5 [500] 14 [2000] 28 [4000]
R1 concrete or mortar
B
3.5 [500] 14 [2000] 28 [4000]
R1 concrete or mortar
B
7.0 [1000] 21 [3000] 28 [4000]
R2 concrete or mortar
B
7.0 [1000] 21 [3000] 28 [4000]
R2 concrete or mortar
B
21 [3000] 35 [5000] 35 [5000]
R3 concrete or mortar
B
21 [3000] 35 [5000] 35 [5000]
R3 concrete or mortar
Bond strength, min, MPa [psi]
— 7 [1000] 10 [1500] —
R1, R2 and R3 concrete or mortar
— 7 [1000] 10 [1500] —
R1, R2, and R3 concrete or mortar
Length change, based on length at 3 h, max, %
allowable increase after 28 days in water +0.15
R1, R2, and R3 concrete
allowable increase after 28 days in water +0.15
R1, R2, and R3 concrete
or mortar
or mortar
allowable decrease after 28 days in air –0.15
Consistency of concrete concrete slump, Flow of mortar,
C
or mortar min, mm [in.] min, %
R1 consistency after 15 min 75 [3] 100
after addition of mixing liquid
R2 and R3 consistency at 5 min after addition of mixing liquid 75 [3] 100
Scaling resistance to deicing
chemicals after 25 cycles of
freezing and thawing
Concrete, max visual rating 2.5
D 2 2
Mortar, max scaled material 5 kg/m [1 lb/ft ]
A
It is recognized that other characteristics of rapid-hardening concrete repair materials might need consideration. Such characteristics might be necessary in some
environments and applications; however, to impose specification limits on all products is considered beyond the scope of this specification. Optional considerations with
suggested methods of test may include tests for the following:
Time of setting Test Method C403/C403M
Flexural strength Test Method C78
Freeze thaw Test Method C666/C666M, Procedure A
Sulfate expansion Test Method C1012
B
The strength at 28 days shall be not less than the strength at 7 days.
C
Slump or flow requirements are waived for materials intended for vertical or overhead applications.
D 2 2
A 250-mm [10-in.] square spalled to an average depth of 3 mm [ ⁄8 in.] for 100 % of its surface would have about 10 kg/m [2.0 lb/ft ] of scaled material.
7. Sampling
7.1 A lot is the quantity of packaged repair material normally placed on a pallet. In general, this quantity will weigh from 900 to
1800 kg [2000 to 4000 lb].
7.2 A unit sample is a single package of material randomly selected from the lot.
8. Specimen Preparation
8.1 Concrete—Mechanically mix the packaged dry concrete material with mixing liquid. Determine the properties of the
unhardened mixture, and mold and cure the specimens in accordance with Practice C192/C192M or modifications as outlined
herein.
8.1.1 The sample of packaged dry material shall be any combination of whole packages yielding not less than 20 L [ ⁄3 ft ] of
hardened material.
8.1.2 Base the quantity of water, other liquid component, or both added to the sample on the quantity per bag stated in the
directions for use.
C928/C928M − 20a
8.1.3 Place the sample in the mixing machine and add the required amount of liquid. Start mixing immediately. Continue mixing
for the length of time indicated in the directions for use.
8.1.4 When making the slump test in accordance with Test Method C143/C143M, schedule work so the test will be completed in
1 1
5 6 ⁄2 min after the mixing liquid is added to the R2 or R3 materials or 15 6 ⁄2 min after mixing the liquid with the R1 materials.
8.1.5 Mold the required number of specimens using additional samples as may be necessary, mixed in accordance with 8.1.1 –
8.1.4. Do not use the mixtures for molding test specimens when the slump is less than that specified in Table 1.
NOTE 1—Where the nominal maximum particle size is not greater than 25 mm [1 in.], the use of cylindrical molds 100 mm [4 in.] in diameter by 200
mm [8 in.] in length is suggested.
8.2 Mortar—Mechanically mix packaged dry mortar material with mixing liquid. Determine the properties of the unhardened
mixture, and mold and cure the specimens in accordance with Test Method C109/C109M or modifications as outlined herein.
8.2.1 The sample of packaged dry material shall weigh 3000 6 3 g [6.6 6 0.005 lb] and shall be representatively obtained from
a whole package in accordance with Practice C702.
8.2.2 Base the quantity of water, or other liquid component, or both added during mixing on the quantity per unit of weight stated
in the directions for use.
8.2.3 When making the flow test in accordance with the section on consistency in Test Method C109/C109M, schedule work so
1 1
the test will be completed in 5 6 ⁄2 min after the start of mixing liquid with the R2 or R3 materials or 15 6 ⁄2 min after mixing
the liquid with the R1 materials.
8.2.4 Mold the required number of specimens using additional samples as necessary mixed in accordance with 8.2.1 – 8.2.3. Do
not use the mixtures for molding test specimens when the flow is less than that specified in Table 1.
8.3 In those cases where the manufacturer has indicated in the package markings, or elsewhere, that the packaged repair material
can be mixed and applied at temperatures that lie beyond the range of 20 6 8 °C [70 6 15 °F], the product must meet the
requirements of Table 1. Specimens must be made and cured in accordance with the procedures of this section. The mixing,
molding and curing temperatures during the first 3 h after molding shall be within 61 °C [62 °F] of the extreme temperature(s)
stated by the manufacturer in the package markings.
9. Test Methods
9.1 Manifestly Faulty Specimens—Treat manifestly faulty specimens in accordance with the corresponding section in Specification
C494/C494M.
9.2 Compressive Strength—Prepare and test three test specimens for each age of test and each level of mixing temperature. Test
in accordance with Test Method C39/C39M for concrete and Test Method C109/C109M for mortar.
9.3 Length Change—Prepare and test three specimens (set) in accordance with Test Method C157/C157M, except as modified by
this section and 8.3. The molds for casting test specimens and the length comparator shall comply with the requirements of Practice
C490/C490M.
9.3.1 Preparation of Specimen Molds and Material Conditioning—The temperature of the mixing water and the materials used
to prepare the test specimens shall be 23 6 2.0 °C [73.5 6 3.5 °F] except as modified by 8.3. The air temperature of the mixing
room, molds and base plates shall be maintained at 23 6 2.0 °C [73.5 6 3.5 °F] and at a relative humidity of not less than 50 %
except if modified by 8.3. Prepare the specimen molds in accordance with the requirements of Practice C490/C490M. Mold
dimensions shall be at least three times the nominal aggregate size. The test specimen for mortar shall be a prism of 25-mm [1-in.]
square cross-section and approximately 285-mm [11 ⁄4-in.] in length. The test specimen for concrete, which all the aggregate passes
a 50-mm [2-in.] sieve, shall be a prism of 100-mm [4-in.] square cross-section and approximately 285-mm
...