ASTM C876-22a

Standard Test Method for Corrosion Potentials of Uncoated Reinforcing Steel in Concrete

SIGNIFICANCE AND USE
4.1 This test method is suitable for in-service evaluation and for use in research and development work.  
4.2 This test method is applicable to members regardless of their size or the depth of concrete cover over the reinforcing steel. Concrete cover in excess of 75 mm (3 in.) can result in an averaging of adjacent reinforcement corrosion potentials that can result in a loss of the ability to discriminate variation in relative corrosion activity.  
4.3 This test method is not applicable to reinforced concrete structures with epoxy-coated reinforcement.  
4.4 This test method is not applicable to reinforced concrete structures in which waterproofing membranes are located between the reinforcement cage and the concrete surface as they can prevent the conduction of electricity and result in erroneous readings.  
4.5 This test method may be used at any time during the life of a concrete member after the concrete has set, although it is generally most useful for evaluating mature reinforced concrete that is suspected to be susceptible to corrosion.  
4.6 The results obtained by the use of this test method shall not be considered as a means for estimating the structural properties of the steel or of the reinforced concrete member.  
4.7 Temperature and humidity can impact potential readings. This is particularly important for periodic testing of the same test location. An increase in the temperature leads to increasing ionic mobility, which in turn affects the reference electrode’s potential. The temperature influence can be neglected if the measurements are taken within the range of 22.2 °C ± 5.5 °C (72 °F ± 10 °F). Otherwise, the temperature-dependency of the measurements must be taken into account.  
4.8 The potential measurements should be interpreted by engineers or technical specialists experienced in the fields of concrete materials and corrosion testing. It is often necessary to use other complementary data such as chloride contents, depth of carbonation, ...
SCOPE
1.1 This test method covers the estimation of the electrical corrosion potential of uncoated reinforcing steel in field and laboratory concrete, for the purpose of determining the corrosion activity of the reinforcing steel.  
1.2 This test method is limited by electrical circuitry. Concrete surface in building interiors and desert environments lose sufficient moisture so that the concrete resistivity becomes so high that special testing techniques not covered in this test method may be required (see 5.1.4.1). Concrete surfaces that are coated or treated with sealers may not provide an acceptable electrical circuit. The basic configuration of the electrical circuit is shown in Fig. 1.
FIG. 1 Reference Electrode Circuitry  
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered 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.  
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: Historical
• Publication Date: 31-Aug-2022
• ICS: 77.140.15 - Steels for reinforcement of concrete
• Technical Committee: G01 - Corrosion of Metals
• Drafting Committee: G01.14 - Corrosion of Metals in Construction Materials

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C876 − 22a
Standard Test Method for
Corrosion Potentials of Uncoated Reinforcing Steel in
1
Concrete
This standard is issued under the fixed designation C876; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E691Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
1.1 This test method covers the estimation of the electrical
G3Practice for Conventions Applicable to Electrochemical
corrosion potential of uncoated reinforcing steel in field and
Measurements in Corrosion Testing
laboratory concrete, for the purpose of determining the corro-
G193Terminology and Acronyms Relating to Corrosion
sion activity of the reinforcing steel.
G16Guide for Applying Statistics to Analysis of Corrosion
1.2 This test method is limited by electrical circuitry.
Data
Concrete surface in building interiors and desert environments
losesufficientmoisturesothattheconcreteresistivitybecomes
3. Terminology
so high that special testing techniques not covered in this test
method may be required (see 5.1.4.1). Concrete surfaces that
3.1 Fordefinitionsoftermsusedinthistestmethod,referto
are coated or treated with sealers may not provide an accept-
Terminology G193.
able electrical circuit. The basic configuration of the electrical
circuit is shown in Fig. 1.
4. Significance and Use
1.3 The values stated in SI units are to be regarded as
4.1 Thistestmethodissuitableforin-serviceevaluationand
standard. The values given in parentheses after SI units are
for use in research and development work.
providedforinformationonlyandarenotconsideredstandard.
4.2 This test method is applicable to members regardless of
1.4 This standard does not purport to address all of the
their size or the depth of concrete cover over the reinforcing
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- steel. Concrete cover in excess of 75 mm (3 in.) can result in
priate safety, health, and environmental practices and deter- an averaging of adjacent reinforcement corrosion potentials
mine the applicability of regulatory limitations prior to use.
that can result in a loss of the ability to discriminate variation
1.5 This international standard was developed in accor-
in relative corrosion activity.
dance with internationally recognized principles on standard-
4.3 Thistestmethodisnotapplicabletoreinforcedconcrete
ization established in the Decision on Principles for the
structures with epoxy-coated reinforcement.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.4 Thistestmethodisnotapplicabletoreinforcedconcrete
Barriers to Trade (TBT) Committee.
structures in which waterproofing membranes are located
between the reinforcement cage and the concrete surface as
2. Referenced Documents
they can prevent the conduction of electricity and result in
2
2.1 ASTM Standards:
erroneous readings.
4.5 Thistestmethodmaybeusedatanytimeduringthelife
1
This test method is under the jurisdiction of ASTM Committee G01 on
of a concrete member after the concrete has set, although it is
Corrosion of Metals and is the direct responsibility of Subcommittee G01.14 on
Corrosion of Metals in Construction Materials.
generally most useful for evaluating mature reinforced con-
Current edition approved Sept. 1, 2022. Published September 2022. Originally
crete that is suspected to be susceptible to corrosion.
approved in 1977. Last previous edition approved in 2022 as C876–22. DOI:
10.1520/C0876-22A.
4.6 The results obtained by the use of this test method shall
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
not be considered as a means for estimating the structural
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
properties of the steel or of the reinforced concrete member.
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C876 − 22a
FIG. 1 Reference Electrode Circuitry
4.7 Temperature and humidity can impact potential read- corrosion potential of reinforcing steel embedded in concrete
ings. This is particularly important for periodic testing of the over the temperature range from 0°C to 49°C (32°F to
same test location. An increase in the temperature leads to 120°F).
increasing ionic mobility, which in turn affects the reference
5.
...

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: C876 − 22 C876 − 22a
Standard Test Method for
Corrosion Potentials of Uncoated Reinforcing Steel in
1
Concrete
This standard is issued under the fixed designation C876; 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 estimation of the electrical corrosion potential of uncoated reinforcing steel in field and laboratory
concrete, for the purpose of determining the corrosion activity of the reinforcing steel.
1.2 This test method is limited by electrical circuitry. Concrete surface in building interiors and desert environments lose sufficient
moisture so that the concrete resistivity becomes so high that special testing techniques not covered in this test method may be
required (see 5.1.4.1). Concrete surfaces that are coated or treated with sealers may not provide an acceptable electrical circuit.
The basic configuration of the electrical circuit is shown in Fig. 1.
1.3 The values stated in inch-poundSI units are to be regarded as standard. The values given in parentheses are mathematical
conversions to after SI units that are provided for information only and are not considered 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.
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
2.1 ASTM Standards:
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
G3 Practice for Conventions Applicable to Electrochemical Measurements in Corrosion Testing
G15G193 Terminology and Acronyms Relating to Corrosion and Corrosion Testing (Withdrawn 2010)
G16 Guide for Applying Statistics to Analysis of Corrosion Data
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology G15G193.
1
This test method is under the jurisdiction of ASTM Committee G01 on Corrosion of Metals and is the direct responsibility of Subcommittee G01.14 on Corrosion of
Metals in Construction Materials.
Current edition approved Aug. 1, 2022Sept. 1, 2022. Published September 2022. Originally approved in 1977. Last previous edition approved in 20152022 as
C876–15.–22. DOI: 10.1520/C0876-22.10.1520/C0876-22A.
2
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C876 − 22a
FIG. 1 Reference Electrode Circuitry
4. Significance and Use
4.1 This test method is suitable for in-service evaluation and for use in research and development work.
4.2 This test method is applicable to members regardless of their size or the depth of concrete cover over the reinforcing steel.
Concrete cover in excess of 3 in. (75 mm)75 mm (3 in.) can result in an averaging of adjacent reinforcement corrosion potentials
that can result in a loss of the ability to discriminate variation in relative corrosion activity.
4.3 This test method is not applicable to reinforced concrete structures with epoxy-coated reinforcement.
4.4 This test method is not applicable to reinforced concrete structures in which waterproofing membranes are located between
the reinforcement cage and the concrete surface as they can prevent the conduction of electricity and result in erroneous readings.
4.5 This test method may be used at any time during the life of a concrete member after the concrete has set, although it is
generally most useful for evaluating mature reinforced concrete that is suspected to be susceptible to corrosion.
4.6 The results obtained by the use of this test method shall not be
...