ASTM A775/A775M-22

Standard Specification for Epoxy-Coated Steel Reinforcing Bars

ABSTRACT
This specification covers deformed and plain steel reinforcing bars with protective epoxy coating applied by the electrostatic spray method. The surface of the steel reinforcing bars to be coated shall be cleaned by abrasive blast cleaning to near-white metal. The number and frequency of tests for coating thickness, continuity, flexibility and adhesion are specified. If the specimen for coating thickness or flexibility fails to meet the specified requirements, two retests on random samples shall be conducted for each failed test.
SCOPE
1.1 This specification covers deformed and plain steel reinforcing bars with protective epoxy coating applied by the electrostatic spray method.
Note 1: The coating applicator is identified throughout this specification as the manufacturer.  
1.2 Other organic coatings may be used provided they meet the requirements of this specification.  
1.3 Requirements for coatings are contained in Annex A1.  
1.4 Requirements for patching material are contained in Annex A2.  
1.5 Guidelines for construction practices at the job-site are presented in Appendix X1.  
1.6 This specification is applicable for orders in either inch-pound units (as Specification A775) or SI units [as Specification A775M].  
1.7 The values stated in either inch-pound units or SI 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.  
1.8 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.  
1.9 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-2022
• ICS: 77.140.15 - Steels for reinforcement of concrete
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.05 - Steel Reinforcement

Relations

• Refers: ASTM G8-24 - Standard Test Methods for Cathodic Disbonding of Coated Steel
• Effective Date: 01-Feb-2024
• Refers: ASTM A1035/A1035M-23a - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 01-Nov-2023
• Refers: ASTM D374/D374M-23 - Standard Test Methods for Thickness of Solid Electrical Insulation
• Effective Date: 01-Oct-2023
• Refers: ASTM G62-23 - Standard Test Methods for Holiday Detection of Coatings used to Protect Pipelines
• Effective Date: 01-Oct-2023
• Refers: ASTM G20-10(2019) - Standard Test Method for Chemical Resistance of Pipeline Coatings
• Effective Date: 01-Oct-2019
• Refers: ASTM A1035/A1035M-19 - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 01-Sep-2019
• Refers: ASTM D2967-07(2017) - Standard Test Method for Corner Coverage of Powder Coatings
• Effective Date: 01-Jun-2017
• Refers: ASTM A1035/A1035M-16b - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 15-Oct-2016
• Refers: ASTM A1035/A1035M-16a - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 01-Mar-2016
• Refers: ASTM A1035/A1035M-16 - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 15-Jan-2016
• Refers: ASTM A996/A996M-15 - Standard Specification for Rail-Steel and Axle-Steel Deformed Bars for Concrete Reinforcement
• Effective Date: 01-Jul-2015
• Refers: ASTM A1035/A1035M-15 - Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
• Effective Date: 01-Jul-2015
• Refers: ASTM A615/A615M-15 - Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
• Effective Date: 01-Apr-2015
• Refers: ASTM A996/A996M-14a - Standard Specification for Rail-Steel and Axle-Steel Deformed Bars for Concrete Reinforcement
• Effective Date: 01-Oct-2014
• Refers: ASTM A615/A615M-14 - Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
• Effective Date: 01-Apr-2014

Overview

ASTM A775/A775M-22: Standard Specification for Epoxy-Coated Steel Reinforcing Bars establishes requirements for deformed and plain steel reinforcing bars coated with a protective epoxy layer. Issued by ASTM International, this standard details the application of epoxy coatings-primarily by the electrostatic spray method-to enhance corrosion resistance in steel reinforcement used in concrete structures. The specification covers requirements from material selection, surface preparation, and coating processes to testing, handling, inspection, and acceptance criteria.

This standard is widely recognized for promoting the long-term durability of reinforced concrete in corrosive environments, ensuring reliable performance in infrastructure and building projects.

Key Topics

• Scope and Applicability

  • Covers both deformed and plain steel reinforcing bars
  • Suitable for applications requiring corrosion protection via epoxy coating
  • Applicable in both inch-pound (A775) and SI (A775M) units

• Epoxy Coating Process

  • Protective epoxy applied using electrostatic spray
  • Steel surfaces must be cleaned by abrasive blast to near-white metal standard
  • Thorough testing for coating thickness, continuity (holidays), flexibility, and adhesion

• Quality and Retesting

  • Sampling and test frequency for confirming coating performance specified
  • Retesting permitted if initial tests on coating thickness or flexibility do not conform

• Material and Surface Preparation

  • Requirements for base steel (e.g., ASTM A615, A706, A996, A1035)
  • Approval guidelines for patching materials and repair processes

• Inspection, Certification, and Handling

  • Inspection procedures established between buyer and manufacturer
  • Handling and storage recommendations minimize coating damage
  • Certification and reporting to validate compliance

• International Standardization Compliance

  • Developed in line with World Trade Organization technical barriers to trade principles

Applications

Epoxy-coated steel reinforcing bars complying with ASTM A775/A775M-22 are widely used in:

• Bridges and Highway Infrastructure

  • Protects steel reinforcement in decks, piers, and abutments against chlorides and deicing agents

• Marine and Coastal Structures

  • Enhances durability of concrete exposed to saltwater and corrosive environments

• Parking Structures

  • Resists aggressive exposure conditions, such as water, salts, and chemicals

• Water Treatment Plants

  • Essential for reinforced concrete tanks and basins subject to chemical exposure

• Buildings in Aggressive Environments

  • Used in basement walls, foundation slabs, and structures where moisture or chemical intrusion is expected

By improving the corrosion resistance of steel rebar, the specification encourages longer service life, reduced maintenance, and predictable performance in critical infrastructure projects.

Related Standards

Several related industry standards complement or are referenced in ASTM A775/A775M-22:

• ASTM A615/A615M: Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
• ASTM A706/A706M: Low-Alloy Steel Bars for Concrete Reinforcement
• ASTM A996/A996M: Rail-Steel and Axle-Steel Deformed Bars
• ASTM A1035/A1035M: Low-Carbon, Chromium Steel Bars
• ASTM B117: Salt Spray (Fog) Testing for Corrosion
• SSPC-SP 10: Surface Preparation Standard for Near-White Blast Cleaning
• SSPC-PA 2: Measurement of Dry Coating Thickness
• ACI 301: Specifications for Structural Concrete

Referencing these standards ensures comprehensive quality control, from the base steel’s properties to surface preparation and coating performance, providing an integrated approach to preventing steel corrosion in reinforced concrete.

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Keywords: ASTM A775, epoxy-coated rebar, steel reinforcing bars, corrosion protection, concrete reinforcement standards, fusion-bonded epoxy, construction materials, rebar coating, infrastructure durability, ASTM standards.

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:A775/A775M −22
Standard Specification for
Epoxy-Coated Steel Reinforcing Bars
This standard is issued under the fixed designationA775/A775M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 2. Referenced Documents
1.1 This specification covers deformed and plain steel 2.1 ASTM Standards:
reinforcing bars with protective epoxy coating applied by the A615/A615MSpecificationforDeformedandPlainCarbon-
electrostatic spray method. Steel Bars for Concrete Reinforcement
A706/A706MSpecification for Deformed and Plain Low-
NOTE 1—The coating applicator is identified throughout this specifica-
Alloy Steel Bars for Concrete Reinforcement
tion as the manufacturer.
A944Test Method for Comparing Bond Strength of Steel
1.2 Other organic coatings may be used provided they meet
Reinforcing Bars to Concrete Using Beam-End Speci-
the requirements of this specification.
mens
1.3 Requirements for coatings are contained in Annex A1.
A996/A996MSpecification for Rail-Steel and Axle-Steel
Deformed Bars for Concrete Reinforcement
1.4 Requirements for patching material are contained in
A1035/A1035M Specification for Deformed and Plain,
Annex A2.
Low-Carbon, Chromium, Steel Bars for Concrete Rein-
1.5 Guidelines for construction practices at the job-site are
forcement
presented in Appendix X1.
B117Practice for Operating Salt Spray (Fog) Apparatus
1.6 This specification is applicable for orders in either
D374/D374MTest Methods for Thickness of Solid Electri-
inch-pound units (as Specification A775) or SI units [as
cal Insulation
Specification A775M].
D2967Test Method for Corner Coverage of Powder Coat-
ings
1.7 The values stated in either inch-pound units or SI units
D4060Test Method for Abrasion Resistance of Organic
are to be regarded separately as standard. The values stated in
Coatings by the Taber Abraser
each system may not be exact equivalents; therefore, each
E2937Guide for Using Infrared Spectroscopy in Forensic
system shall be used independently of the other. Combining
Paint Examinations
values from the two systems may result in non-conformance
G8Test Methods for Cathodic Disbonding of Pipeline Coat-
with the standard.
ings
1.8 This standard does not purport to address all of the
G14TestMethodforImpactResistanceofPipelineCoatings
safety concerns, if any, associated with its use. It is the
(Falling Weight Test)
responsibility of the user of this standard to establish appro-
G20Test Method for Chemical Resistance of Pipeline Coat-
priate safety, health, and environmental practices and deter-
ings
mine the applicability of regulatory limitations prior to use.
G62Test Methods for Holiday Detection in Pipeline Coat-
1.9 This international standard was developed in accor-
ings
dance with internationally recognized principles on standard-
2.2 NACE Standards:
ization established in the Decision on Principles for the
RP-287-87Field Measurement of Surface Profile of Abra-
Development of International Standards, Guides and Recom-
sive Blast-Cleaned Steel Surface Using a Replica Tape
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1 2
This specification is under the jurisdiction ofASTM Committee A01 on Steel, For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
A01.05 on Steel Reinforcement. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Sept. 1, 2022. Published November 2022. Originally the ASTM website.
approved in 1981. Last previous edition approved in 2019 as A775/A775M – 19. Available from NACE International (NACE), 1440 South Creek Dr., Houston,
DOI: 10.1520/A0775_A0775M-22. TX 77084-4906, http://www.nace.org.
*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
A775/A775M−22
2.3 SSPC Specifications: 4.2.4 Specific requirements for test frequency (9.1),
SSPC-PA2Measurement of Dry Coating Thickness with 4.2.5 A report of the results of the tests performed on the
Magnetic Gages coated steel reinforcing bars (14.1),
SSPC-SP10Near-White Blast Cleaning 4.2.6 Requirements for inspection (12.1),
SSPC-VIS1Pictorial Surface Preparation Standards for 4.2.7 Manufacturer qualification and certification require-
Painting Steel Surfaces ments (if any), and
4.2.8 Other special requirements, if any.
2.4 CRSI Documents:
“Voluntary Certification Program for Fusion Bonded Epoxy
NOTE2—Itisrecommendedthatthecoatingapplicationproceduresand
Coating Applicator Plants”
processes be audited by an independent certification program for epoxy
coating applicator plants such as that provided by the Concrete Reinforc-
2.5 ACI Standards:
ing Steel Institute, or equivalent.
ACI301Specifications for Structural Concrete
NOTE 3—Deformed Grade 60 bars toASTM A615 – _____; 20000 ft,
No. 6, 40 ft 0 in. long in secured lifts with sufficient spacers or padding,
3. Terminology
or both; epoxy-coated to ASTM A775 – _____; including written
certifications for the powder coating and coated bars, and 1 qt of patching
3.1 Definitions of Terms Specific to This Standard:
material.
3.1.1 conversion coating, n—preparation of the blast-
[Atypicalorderingdescriptionisasfollows:DeformedGrade420bars
cleaned steel surface prior to coating application that is
to ASTM A615M – _____; 6000 m, No. 19, 12 m long in secured lifts
designed to pretreat the metal to promote coating adhesion,
with sufficient spacers or padding, or both; epoxy-coated to ASTM
A775M – _____; including written certifications for the powder coating
reduce metal-coating reactions, improve corrosion resistance,
and coated bars, and 1 L of patching material.]
and increase blister resistance.
3.1.2 disbonding, n—loss of adhesion between the fusion-
5. Materials
bonded epoxy coating and the steel reinforcing bar.
5.1 Steel reinforcing bars to be coated shall meet the
3.1.3 fusion-bonded epoxy coating, n—product containing
requirements of one of the following specifications: A615,
pigments, thermosetting epoxy resins, crosslinking agents, and
A706, A996, or A1035 [A615M, A706M, A996M, or
other additives, which is applied in the form of a powder onto
A1035M], as specified by the purchaser and shall be free of
a clean, heated metallic substrate and fuses to form a continu-
contaminants such as oil, grease, or paint.
ous barrier coating.
NOTE4—Priortocoating,thesteelreinforcingbarsshouldbeinspected
3.1.4 holiday, n—discontinuity in a coating that is not
fortheirsuitabilityforcoating.Barswithsharpedgesonthedeformations,
discernible to a person with normal or corrected vision. rolled-in slivers, or other surface imperfections are difficult to coat
properly and should not be coated. The coating will flow away from the
3.1.5 patching material, n—liquid two-part epoxy coating
sharpedgesandmayresultininadequatecoatingthicknessatthesepoints.
used to repair damaged coating and to coat uncoated areas on
5.2 The powder coating shall meet the requirements of
the surface of a coated bar.
AnnexA1. Upon request, the purchaser shall be provided with
3.1.6 wetting agent, n—material that lowers the surface
the test report for review.
tension of water allowing it to penetrate more effectively into
5.2.1 A written certification shall be furnished to the pur-
small discontinuities in the coating, giving a more accurate
chaserthatproperlyidentifiesthenumberofeachlotofpowder
indication of the holiday count.
coatingusedintheorder,materialquantityrepresented,dateof
manufacture, name and address of the powder coating
4. Ordering Information
manufacturer,andastatementthatthesuppliedpowdercoating
4.1 Ordersforepoxy-coatedsteelreinforcingbarsunderthis
is the same composition as that qualified according to Annex
specification shall contain the following information:
A1 of this specification.
4.1.1 Specificationandyearofissueforthereinforcingbars
5.2.2 The powder coating shall be stored in a temperature-
to be coated (5.1),
controlled environment following the written recommenda-
4.1.2 Quantity of bars,
tions of the powder coating manufacturer until ready for use.
4.1.3 Size and grade of bars, and
At that point, if the storage temperature is below the plant
4.1.4 ASTM designation A775 [A775M] and year of issue.
ambient temperature, the powder coating shall be given suffi-
cient time to reach approximate plant ambient temperature.
4.2 Thepurchasershallhavetheoptiontospecifyadditional
The powder coating shall be used within the powder coating
requirements, including but not limited to the following:
manufacturer’s written recommended shelf life.
4.2.1 Requirements for review of test data to demonstrate
that the powder coating meets Annex A1 (5.2),
5.3 If specified in the order, a representative 8-oz [0.2-kg]
4.2.2 Representative sample of epoxy powder coating (5.3),
sampleofthepowdercoatingshallbesuppliedtothepurchaser
4.2.3 Quantity of patching material (5.4.4),
from each batch. The sample shall be packaged in an airtight
container and identified by batch number.
5.4 Patching material for repairing damaged coating and
Available from Society for Protective Coatings (SSPC), 40 24th St., 6th Floor,
Pittsburgh, PA 15222-4656, http://www.sspc.org.
uncoatedareasshallbeinertinconcreteandfeasibleforrepairs
Available from Concrete Reinforcing Steel Institute (CRSI), 933 North Plum
at the applicator plant or at the fabricating shop.
Grove Rd., Schaumburg, IL 60173–4758, http://www.crsi.org.
5.4.1 The powder coating manufacturer shall specify the
AvailablefromAmericanConcreteInstitute(ACI),P.O.Box9094,Farmington
Hills, MI 48333-9094, http://www.concrete.org. approved patching material to be used with their powder.
A775/A775M−22
NOTE 8—The use of infrared and temperature-indicating crayon mea-
5.4.2 Patching material shall be approved in accordance
surement of the steel reinforcing bars is recommended.
with Annex A2 in this specification prior to use.
5.4.3 The patching material manufacturer shall specify the 7.3 The powder coating shall be applied by electrostatic
method of metal surface preparation, and the procedures for spray or other suitable method.
application of the patching material.
8. Requirements for Coated Steel Reinforcing Bars
5.4.4 If specified in the order, patching material shall be
supplied to the purchaser. 8.1 Coating Thickness:
8.1.1 Thecoatingthicknessmeasurementsaftercuringshall
6. Surface Preparation
be7to12mils[175to300µm]forbarssizesNos.3to5[Nos.
10 to 16] and 7 to 16 mils [175 to 400 µm] for bar sizes Nos.
6.1 The surface of the steel reinforcing bars to be coated
shall be cleaned by abrasive blast cleaning to near-white metal 6 to 18 [Nos. 19 to 57]. The upper thickness limit shall not
apply to repaired areas of damaged coating.
in accordance with SSPC-SP10.Additional surface treatment,
as indicated in 6.3, is permitted. 8.1.2 A single recorded steel reinforcing bar coating thick-
ness measurement is the average of three individual gage
6.1.1 UseofSSPC-VIS1asavisualstandardofcomparison
to define the final surface condition is permitted. readings obtained between four consecutive deformations. A
minimum of five recorded measurements shall be taken ap-
6.1.2 Average blast profile maximum roughness depth read-
ings of 1.5 to 4.0 mils [0.04 to 0.10 mm], as determined by proximately evenly spaced along each side of the test speci-
mens (a minimum of ten recorded measurements per bar).
replica tape measurements using NACE RP-287-87, shall be
considered suitable as an anchor pattern. 8.1.3 For acceptance purposes, the average of all recorded
coating thickness measurements shall not be less than the
NOTE 5—The use of a “profilometer” type surface measurement
specified minimum thickness or more than the specified
instrument that measures the peak count as well as the maximum profile
maximum thickness. No single recorded coating thickness
depth is recommended.
NOTE 6—Abrasive blast cleaning of steel reinforcing bars with a high
measurementshallbelessthan80%ofthespecifiedminimum
degree (>90%) of grit in the cleaning media provides the most suitable
thickness or more than 120 % of the specified maximum
anchor profile for coating adhesion. After grit has been recycled, a small
thickness.
portion will take on the appearance of shot.
8.1.4 Measurements shall be made in accordance with
6.2 Multidirectional, high-pressure dry air knives shall be
SSPC-PA2, following the instructions for calibration and use
used after blasting to remove dust, grit, and other foreign
recommended by the thickness gage manufacturer. Pull-off or
matterfromtheblast-cleanedsteelsurface.Theairknivesshall
fixed probe gages shall be used. “Pencil-type” pull-off gages
not deposit oil on the steel reinforcing bars.
that require the operator to observe the reading at the instant
the magnet is pulled from the surface shall not be used.
NOTE 7—It is recommended that incoming steel reinforcing bars and
blast media be checked for salt contamination prior to use. Blast media
8.1.5 The coating thickness shall be measured on the body
found to be salt contaminated should be rejected. Steel reinforcing bars
of a straight length of steel reinforcing bar between the
found to be salt contaminated from exposure to deicing salts or salt spray
deformations.
should be cleaned by acid washing or other suitable methods to remove
salt contaminants from the surface prior to blast cleaning.
8.2 Coating Continuity:
8.2.1 The manufacturer’s plant shall have an operational
6.3 It shall be permissible for the manufacturer to use a
in-line 67.5 V, 80 000 Ω, wet-sponge type direct-current
chemical wash or conversion of the blast-cleaned steel rein-
holiday detector or equivalent method with an automated
forcing bar surface, or both, to enhance coating adhesion.This
holiday counting system to determine the acceptability of the
pretreatmentshallbeappliedafterabrasivecleaningandbefore
epoxy-coated steel reinforcing bars prior to shipment.
coating,inaccordancewiththewrittenapplicationinstructions
8.2.2 If in-line detector or equivalent method is inoperable
specified by the pretreatment manufacturer.
or unavailable, an off-line holiday detector or handheld detec-
7. Coating Application
tor shall be permitted provided that 100 % of the epoxy-coated
steel reinforcing bars are tested and all holiday counts are
7.1 If pretreatment is used in the preparation of the surface,
recorded.
the powder coating shall be applied to the cleaned and
pretreatedsteelreinforcingbarsurfaceassoonaspossibleafter
NOTE 9—Handheld holiday detector checks should be performed each
surface treatments have been completed, and before visible
production day to verify the accuracy of the in-line system. Handheld
holiday detectors offer a reliable way to correlate data obtained from the
oxidation of the surface occurs as discernible to a person with
in-line holiday detector and automated counting system.
normal or corrected vision. In no case shall application of the
coating be delayed more than 3 h after cleaning. 8.2.3 On average, there shall not be more than 3 holidays
per metre [one holiday per foot] on a coated steel reinforcing
7.2 The fusion-bonded epoxy powder coating shall be
bar. The average applies to the full production length of a bar.
appliedinaccordancewiththewrittenrecommendationsofthe
8.2.4 Awetting agent shall be used in accordance with Test
manufacturer of the powder coating for initial steel surface
Methods G62 in the inspection for holidays on the coated steel
temperature range and post application curing requirements.
reinforcing bars.
During continuous operations, the temperature of the surface
immediately prior to coating shall be measured using infrared 8.3 Coating Flexibility:
guns or temperature indicating crayons, or both, at least once 8.3.1 The coating flexibility shall be evaluated by bending
every 30 min. production coated steel reinforcing bars at a uniform rate
A775/A775M−22
aroundamandrelofspecifiedsizewithinamaximumspecified 9.2.3 Random tests shall be made for coating continuity.
time period as prescribed in Table 1. The two longitudinal ribs
10. Retests
shall be placed in a plane perpendicular to the mandrel radius.
The test specimens shall be between 68°F and 86°F [20°C 10.1 Ifthespecimenforcoatingthicknessorflexibilityfails
and 30°C].
to meet the specified requirements, two retests on random
8.3.2 Cracking or disbonding of the coating on the outside samplesshallbeconductedforeachfailedtest.Iftheresultsof
radius of the bent bar visible to a person with normal or
both retests meet the specified requirements, the coated steel
corrected vision shall be considered cause for rejection of the reinforcing bars represented by the samples shall be accepted.
coated steel reinforcing bars represented by the bend test
11. Permissible Amount of Damaged Coating and Repair
sample.
of Damaged Coating
NOTE 10—The qualification requirements for coating flexibility (see
11.1 The maximum amount of repaired damaged coating
A1.3.6.1) prescribe bending a No. 6 [No. 19] deformed bar around a 6-in.
[150-mm] diameter mandrel. The bend test requirements in Table 1 for shall not exceed 1% of the total surface area in each 1-ft [0.3
evaluating the coating flexibility of production-coated steel reinforcing
m] of the bar.This limit on repaired damaged coating shall not
bars, for bar sizes Nos. 3 to 8 [Nos. 10 to 25], are not compatible with
include sheared or cut ends that are coated with patching
fabrication bending practices. Finished bend diameters for bar sizes Nos.
material (see 11.4).
3 to 8 [Nos. 10 to 25] used in actual construction are smaller than the
mandrel diameters in Table 1. Thus, the finished bends of production-
11.2 All damaged coating due to fabrication and handling
coated bars, particularly the smaller bar sizes used for stirrups and ties,
(to the point of shipment to the job-site) shall be repaired with
should be examined closely for hairline cracking on the outside radius of
patching material conforming to Annex A2.
the bent bar. If hairline cracking is present, it should be repaired with
patching material.
NOTE 11—If the amount of repaired damaged coating in any 1-ft
[0.3-m] length of a coated bar, exceeds 1%, that section should be
8.3.3 A test in which fracture or partial failure of the steel
removed from the coated steel reinforcing bar and discarded. In patching
reinforcing bar, or cracking or disbonding caused by imperfec-
damaged coating , care should be taken not to apply the patching material
tions in the bar surface visible after performing the bend test
over an excessive area of the intact coating during the repair process.Too
occurs, shall be considered an invalid test and the test shall be
large an area of thick patching material especially on smaller-size
repeated on a new specimen.
reinforcing bars is likely to cause a reduction in bond strength of the bars
to concrete.
8.4 The requirements for coated steel reinforcing bars shall
11.3 Repairedareasshallhaveaminimumcoatingthickness
be met at the manufacturer’s plant prior to shipment.
of 7 mils [175 µm].
9. Number of Tests
11.4 When coated bars are sheared, saw-cut, or cut by other
9.1 The purchaser shall have the option to specify the
means during the fabrication process, the cut ends shall be
sampling and test schedule for the number and frequency of coated with patching material. Coated steel reinforcing bars
tests for coating thickness, continuity, and flexibility.
shall not be flame cut.
9.2 Ifthenumberandfrequencyoftestsarenotspecifiedby 11.5 Repair of damaged coating shall be performed in
the purchaser the following apply:
accordance with the patching material manufacturer’s written
9.2.1 Tests for coating thickness shall be made on a mini- recommendations.
mum of two bars of each size every two production hours,
12. Inspection
9.2.2 Bendtestsforcoatingflexibilityshallbeconductedon
at least one bar of each size every four production hours, and
12.1 Inspection of the epoxy-coated steel reinforcing bars
shall be agreed upon between the purchaser and the manufac-
turer as part of the purchase order or contract.
TABLE 1 Bend Test Requirements
A615, A706, A615M, A706M,
13. Rejection
A996, or A1035 A996M, or A1035M
Bend 13.1 Coated steel reinforcing bars represented by test speci-
Time to
Mandrel Mandrel Angle
mens that do not meet the requirements of this specification
Bar Bar Comple-
Diameter, Diameter, (After
No. No. tion max,
A A shall be rejected and marked with a contrasting color paint or
in. mm Rebound,
s
degrees) other suitable identification. At the manufacturer’s option, the
3 3 10 75 180 15 affected lot shall be replaced or, alternatively, stripped of
4 4 13 100 180 15
coating, recleaned, recoated, and resubmitted for acceptance
5 5 16 125 180 15
testing in accordance with the requirements of this specifica-
6 6 19 150 180 15
7 7 22 175 180 45 tion.
8 8 25 200 180 45
NOTE 12—If the coating is not to be stripped from the rejected steel
9 9 29 230 180 45
10 10 32 250 180 45 reinforcing bars, the bars should be scrapped or with the purchaser’s
11 11 36 280 180 45
approval used as uncoated steel reinforcing bars.
14 17 43 430 90 45
18 23 57 580 90 45
14. Certification
A
Mandreldiametersspecifiedforsimilarsize(shownonthesameline)inch-pound
14.1 The purchaser shall be furnished with, at the time of
and metric bars may be interchanged.
shipment, written certification that samples representing each
A775/A775M−22
lot of coated steel reinforcing bars have been either tested or bundles of coated steel reinforcing bars. The bars or bundles
inspected as directed in this specification and the requirements shall not be dropped or dragged.
have been met. When specified in the purchase order or
15.2 If circumstances require storing coated steel reinforc-
contract, a report of the test results shall be furnished.
ingbarsoutdoorsformorethantwomonths,protectivestorage
measures shall be implemented to protect the material from
14.2 A Material Test Report, Certificate of Inspection, or
sunlight, salt spray and weather exposure. If the manufacturer
similar document printed from or used in electronic form from
storescoatedsteelreinforcingbarsoutdoorswithoutprotective
an electronic data interchange (EDI) transmission shall be
covering,thedateonwhichthecoatedbarsareplacedoutdoors
regardedashavingthesamevalidityasacounterpartprintedin
shall be recorded on the identification tag on the bundled steel.
the certifier’s facility. The content of the EDI transmitted
Coated steel reinforcing bars, whether individual bars or
document must meet the requirements of the invoked ASTM
bundles of bars, or both, shall be covered with opaque
standard(s) and conform to any EDI agreement between the
polyethylene sheeting or other suitable opaque protective
purchaser and the supplier. Notwithstanding the absence of a
material. For stacked bundles, the protective covering shall be
signature, the organization submitting the EDI transmission is
drapedaroundtheperimeterofthestack.Thecoveringshallbe
responsible for the content of the report.
secured adequately, and allow for air circulation around the
bars to minimize condensation under the covering.
NOTE13—Theindustrydefinitioninvokedhereis:EDIisthecomputer-
to-computer exchange of business information in a standard format such
15.3 Coated steel reinforcing bars, whether individual bars
as ANSI ASC X12.
or bundles of bars, or both, shall be stored off the ground on
protective cribbing.
15. Handling and Identification
15.4 The identification of all steel reinforcing bars shall be
15.1 All systems for handling coated steel reinforcing bars
maintained throughout the coating and fabrication processes to
shall have padded contact areas. All bundling bands shall be
the point of shipment.
padded or suitable banding shall be used to prevent damage to
16. Keywords
thecoating.Allbundlesofcoatedsteelreinforcingbarsshallbe
lifted with a strong back, spreader bar, multiple supports, or a 16.1 coating requirements; concrete reinforcement; corro-
platform bridge to prevent bar-to-bar abrasion from sags in the sion resistance; epoxy coating; steel bars
ANNEXES
(Mandatory Information)
A1. REQUIREMENTS FOR ORGANIC COATINGS FOR STEEL REINFORCING BARS
A1.1 Powder Coatings A1.2.3 Test Specimens:
A1.2.3.1 The following specimens shall be submitted as a
A1.1.1 This annex covers qualification requirements for
minimum for test:
barrier organic coatings for protecting steel reinforcing bars
(1) Fourteen 4-ft [1.2-m] long No. 6, Grade 60 [No. 19,
from corrosion.
Grade 420] deformed steel reinforcing bars, with a coating
A1.1.2 The powder coating shall be of organic composition
thickness of 7mils to 12 mils [175µm to 300 µm],
except for the pigment which may be inorganic if used.
(2) Six uncoated and uncleaned No. 6 [No. 19] steel
A1.2 Test Materials reinforcing bars, 4-ft [1.2-m] long, and from the same lot of
steel as the coated bars,
A1.2.1 A 1-lb [0.5-kg] sample of the powder coating with
(3) Four4in.by4in.by0.05in.[100mmby100mmby
its generic description and its infrared spectrum shall be
1.3mm]steelplateswithcenterholesforTaberabraserscoated
submitted to the testing agency.The infrared spectrum shall be
to a thickness of 10mils 6 2 mils [250µm 6 50 µm].
obtainedwithFourierTransformInfraredSpectroscopy(FTIR)
(4) Four free films of coating material with a thickness of
usingGuideE2937.Thespectrumandgenericdescriptionshall
7milsto9mils[175µmto225µm].Thefilmsshallbeatleast
become an integral part of the qualification test report.
4in. by 4 in. [100mm by 100 mm].
NOTE A1.1—The infrared spectrum uniquely identifies the powder
(5) Fourteen coated No. 6 [No. 19] steel reinforcing bars,
sample.
10-in. [0.25-m] long, coated to a thickness of 7mils to 12 mils
A1.2.2 Asample of patching material conforming to Annex
[175µm to 300 µm]. The coated steel reinforcing bars shall
A2 shall be submitted to the testing agency.The product name
have their ends sealed with patching material.
and a description of the patching material shall be given in the
A1.2.3.2 Steel reinforcing bars with a nominal diameter
test report.
within 60.04 in. [61 mm] of No. 6 [No. 19] bars shall be
acceptable for qualification testing.
A775/A775M−22
A1.2.3.3 The coating on the bars and films tested shall be A1.3.3.2 The anode shall be a 6-in. [150-mm] long solid
free of holes, voids, contamination, cracks and damaged areas. platinum electrode (0.06 in. [1.6 mm] nominal diameter) or
The coated bars shall be checked for holidays using a 67.5-V, platinized wire (0.125 in. [3.2 mm] nominal diameter);
80 000-Ω, wet-sponge type dc holiday detector in accordance A1.3.3.3 A calomel reference electrode shall be used;
withTestMethodsG62.Thetotalnumberofholidaysfoundon A1.3.3.4 The electrolyte solution shall be 3% NaCl by
the bar specimens tested shall be reported. mass dissolved in distilled water;
A1.2.3.4 Coating thickness measurements shall be made in A1.3.3.5 Theelectrolytesolutiontemperatureshallbe75°F
accordance with 8.1. 6 3.6°F [24°C 6 2°C];
...

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: A775/A775M − 19 A775/A775M − 22
Standard Specification for
Epoxy-Coated Steel Reinforcing Bars
This standard is issued under the fixed designation A775/A775M; 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*
1.1 This specification covers deformed and plain steel reinforcing bars with protective epoxy coating applied by the electrostatic
spray method.
NOTE 1—The coating applicator is identified throughout this specification as the manufacturer.
1.2 Other organic coatings may be used provided they meet the requirements of this specification.
1.3 Requirements for coatings are contained in Annex A1.
1.4 Requirements for patching material are contained in Annex A2.
1.5 Guidelines for construction practices at the job-site are presented in Appendix X1.
1.6 This specification is applicable for orders in either inch-pound units (as Specification A775) or SI units [as Specification
A775M].
1.7 The values stated in either inch-pound units or SI 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.
1.8 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.
1.9 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 A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.05
on Steel Reinforcement.
Current edition approved June 1, 2019Sept. 1, 2022. Published June 2019November 2022. Originally approved in 1981. Last previous edition approved in 20172019 as
A775/A775M – 17.19. DOI: 10.1520/A0775_A0775M-19.10.1520/A0775_A0775M-22.
*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
A775/A775M − 22
2. Referenced Documents
2.1 ASTM Standards:
A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
A706/A706M Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete Reinforcement
A944 Test Method for Comparing Bond Strength of Steel Reinforcing Bars to Concrete Using Beam-End Specimens
A996/A996M Specification for Rail-Steel and Axle-Steel Deformed Bars for Concrete Reinforcement
A1035/A1035M Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement
B117 Practice for Operating Salt Spray (Fog) Apparatus
D374/D374M Test Methods for Thickness of Solid Electrical Insulation
D2967 Test Method for Corner Coverage of Powder Coatings
D4060 Test Method for Abrasion Resistance of Organic Coatings by the Taber Abraser
E2937 Guide for Using Infrared Spectroscopy in Forensic Paint Examinations
G8 Test Methods for Cathodic Disbonding of Pipeline Coatings
G14 Test Method for Impact Resistance of Pipeline Coatings (Falling Weight Test)
G20 Test Method for Chemical Resistance of Pipeline Coatings
G62 Test Methods for Holiday Detection in Pipeline Coatings
2.2 NACE Standards:
RP-287-87 Field Measurement of Surface Profile of Abrasive Blast-Cleaned Steel Surface Using a Replica Tape
2.3 SSPC Specifications:
SSPC-PA 2 Measurement of Dry Coating Thickness with Magnetic Gages
SSPC-SP 10 Near-White Blast Cleaning
SSPC-VIS 1 Pictorial Surface Preparation Standards for Painting Steel Surfaces
2.4 CRSI Documents:
“Voluntary Certification Program for Fusion Bonded Epoxy Coating Applicator Plants”
2.5 ACI Standards:
ACI 301 Specifications for Structural Concrete
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 conversion coating, n—preparation of the blast-cleaned steel surface prior to coating application that is designed to pretreat
the metal to promote coating adhesion, reduce metal-coating reactions, improve corrosion resistance, and increase blister
resistance.
3.1.2 disbonding, n—loss of adhesion between the fusion-bonded epoxy coating and the steel reinforcing bar.
3.1.3 fusion-bonded epoxy coating, n—product containing pigments, thermosetting epoxy resins, crosslinking agents, and other
additives, which is applied in the form of a powder onto a clean, heated metallic substrate and fuses to form a continuous barrier
coating.
3.1.4 holiday, n—discontinuity in a coating that is not discernible to a person with normal or corrected vision.
3.1.5 patching material, n—liquid two-part epoxy coating used to repair damaged or uncoated areas. coating and to coat uncoated
areas on the surface of a coated bar.
3.1.6 wetting agent, n—material that lowers the surface tension of water allowing it to penetrate more effectively into small
discontinuities in the coating, giving a more accurate indication of the holiday count.
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.
Available from NACE International (NACE), 1440 South Creek Dr., Houston, TX 77084-4906, http://www.nace.org.
Available from Society for Protective Coatings (SSPC), 40 24th St., 6th Floor, Pittsburgh, PA 15222-4656, http://www.sspc.org.
Available from Concrete Reinforcing Steel Institute (CRSI), 933 North Plum Grove Rd., Schaumburg, IL 60173–4758, http://www.crsi.org.
Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http://www.concrete.org.
A775/A775M − 22
4. Ordering Information
4.1 Orders for epoxy-coated steel reinforcing bars under this specification shall contain the following information:
4.1.1 Specification and year of issue for the reinforcing bars to be coated (5.1),
4.1.2 Quantity of bars,
4.1.3 Size and grade of bars, and
4.1.4 ASTM designation A775 [A775M] and year of issue.
4.2 The purchaser shall have the option to specify additional requirements, including but not limited to the following:
4.2.1 Requirements for review of test data to demonstrate that the powder coating meets Annex A1 (5.2),
4.2.2 Representative sample of epoxy powder coating (5.3),
4.2.3 Quantity of patching material (5.4.25.4.4),
4.2.4 Specific requirements for test frequency (9.1),
4.2.5 A report of the results of the tests performed on the coated steel reinforcing bars (14.1),
4.2.6 Requirements for inspection (12.1),
4.2.7 Manufacturer qualification and certification requirements (if any), and
4.2.8 Other special requirements, if any.
NOTE 2—It is recommended that the coating application procedures and processes be audited by an independent certification program for epoxy coating
applicator plants such as that provided by the Concrete Reinforcing Steel Institute, or equivalent.
NOTE 3—Deformed Grade 60 bars to ASTM A615 – _____; 20 000 ft, No. 6, 40 ft 0 in. long in secured lifts with sufficient spacers or padding, or both;
epoxy-coated to ASTM A775 – _____; including written certifications for the powder coating and coated bars, and 1 qt of patching material.
[A typical ordering description is as follows: Deformed Grade 420 bars to ASTM A615M – _____; 6000 m, No. 19, 12 m long in secured lifts with
sufficient spacers or padding, or both; epoxy-coated to ASTM A775M – _____; including written certifications for the powder coating and coated bars,
and 1 L of patching material.]
5. Materials
5.1 Steel reinforcing bars to be coated shall meet the requirements of one of the following specifications: A615, A706, A996, or
A1035 [A615M, A706M, A996M, or A1035M], as specified by the purchaser and shall be free of contaminants such as oil, grease,
or paint.
NOTE 4—Prior to coating, the steel reinforcing bars should be inspected for their suitability for coating. Bars with sharp edges on the deformations,
rolled-in slivers, or other surface imperfections are difficult to coat properly and should not be coated. The coating will flow away from the sharp edges
and may result in inadequate coating thickness at these points.
5.2 The powder coating shall meet the requirements of Annex A1. Upon request, the purchaser shall be provided with the test
report for review.
5.2.1 A written certification shall be furnished to the purchaser that properly identifies the number of each lot of powder coating
used in the order, material quantity represented, date of manufacture, name and address of the powder coating manufacturer, and
a statement that the supplied powder coating is the same composition as that qualified according to Annex A1 of this specification.
5.2.2 The powder coating shall be stored in a temperature-controlled environment following the written recommendations of the
powder coating manufacturer until ready for use. At that point, if the storage temperature is below the plant ambient temperature,
A775/A775M − 22
the powder coating shall be given sufficient time to reach approximate plant ambient temperature. The powder coating shall be used
within the powder coating manufacturer’s written recommended shelf life.
5.3 If specified in the order, a representative 8-oz [0.2-kg] sample of the powder coating shall be supplied to the purchaser from
each batch. The sample shall be packaged in an airtight container and identified by batch number.
5.4 Patching material for repairing damaged coating shall be compatible with the coating, and uncoated areas shall be inert in
concrete,concrete and feasible for repairs at the applicator plant or at the fabricating shop. Patching material shall be approved in
accordance with Annex A2 prior to use.
5.4.1 The powder coating manufacturer shall specify the approved patching material to be used with their powder.
5.4.2 Patching material shall be approved in accordance with Annex A2 in this specification prior to use.
5.4.3 The patching material manufacturer shall specify the metals method of metal surface preparation, and the procedures for
application of the patching material.
5.4.4 If specified in the order, patching material conforming to Annex A2 and recommended by the powder coating manufacturer
shall be supplied to the purchaser.
6. Surface Preparation
6.1 The surface of the steel reinforcing bars to be coated shall be cleaned by abrasive blast cleaning to near-white metal in
accordance with SSPC-SP 10. Additional surface treatment, as indicated in 6.3, is permitted.
6.1.1 Use of SSPC-VIS 1 as a visual standard of comparison to define the final surface condition is permitted.
6.1.2 Average blast profile maximum roughness depth readings of 1.5 to 4.0 mils [0.04 to 0.10 mm], as determined by replica tape
measurements using NACE RP-287-87, shall be considered suitable as an anchor pattern.
NOTE 5—The use of a “profilometer” type surface measurement instrument that measures the peak count as well as the maximum profile depth is
recommended.
NOTE 6—Abrasive blast cleaning of steel reinforcing bars with a high degree (>90 %) of grit in the cleaning media provides the most suitable anchor
profile for coating adhesion. After grit has been recycled, a small portion will take on the appearance of shot.
6.2 Multidirectional, high-pressure dry air knives shall be used after blasting to remove dust, grit, and other foreign matter from
the blast-cleaned steel surface. The air knives shall not deposit oil on the steel reinforcing bars.
NOTE 7—It is recommended that incoming steel reinforcing bars and blast media be checked for salt contamination prior to use. Blast media found to
be salt contaminated should be rejected. Steel reinforcing bars found to be salt contaminated from exposure to deicing salts or salt spray should be cleaned
by acid washing or other suitable methods to remove salt contaminants from the surface prior to blast cleaning.
6.3 It shall be permissible for the manufacturer to use a chemical wash or conversion of the blast-cleaned steel reinforcing bar
surface, or both, to enhance coating adhesion. This pretreatment shall be applied after abrasive cleaning and before coating, in
accordance with the written application instructions specified by the pretreatment manufacturer.
7. Coating Application
7.1 If pretreatment is used in the preparation of the surface, the powder coating shall be applied to the cleaned and pretreated steel
reinforcing bar surface as soon as possible after surface treatments have been completed, and before visible oxidation of the surface
occurs as discernible to a person with normal or corrected vision. In no case shall application of the coating be delayed more than
3 h after cleaning.
7.2 The fusion-bonded epoxy powder coating shall be applied in accordance with the written recommendations of the
manufacturer of the powder coating for initial steel surface temperature range and post application curing requirements. During
continuous operations, the temperature of the surface immediately prior to coating shall be measured using infrared guns or
A775/A775M − 22
temperature indicating crayons, or both, at least once every 30 min.
A775/A775M − 22
NOTE 8—The use of infrared and temperature-indicating crayon measurement of the steel reinforcing bars is recommended.
7.3 The powder coating shall be applied by electrostatic spray or other suitable method.
8. Requirements for Coated Steel Reinforcing Bars
8.1 Coating Thickness:
8.1.1 The coating thickness measurements after curing shall be 7 to 12 mils [175 to 300 μm] for bars sizes Nos. 3 to 5 [Nos. 10
to 16] and 7 to 16 mils [175 to 400 μm] for bar sizes Nos. 6 to 18 [Nos. 19 to 57]. The upper thickness limit shall not apply to
repaired areas of damaged coating.
8.1.2 A single recorded steel reinforcing bar coating thickness measurement is the average of three individual gage readings
obtained between four consecutive deformations. A minimum of five recorded measurements shall be taken approximately evenly
spaced along each side of the test specimens (a minimum of ten recorded measurements per bar).
8.1.3 For acceptance purposes, the average of all recorded coating thickness measurements shall not be less than the specified
minimum thickness or more than the specified maximum thickness. No single recorded coating thickness measurement shall be
less than 80 % of the specified minimum thickness or more than 120 % of the specified maximum thickness.
8.1.4 Measurements shall be made in accordance with SSPC-PA 2, following the instructions for calibration and use recommended
by the thickness gage manufacturer. Pull-off or fixed probe gages shall be used. “Pencil-type” pull-off gages that require the
operator to observe the reading at the instant the magnet is pulled from the surface shall not be used.
8.1.5 The coating thickness shall be measured on the body of a straight length of steel reinforcing bar between the deformations.
8.2 Coating Continuity:
8.2.1 The manufacturer’s plant shall have an operational in-line 67.5 V, 80 000 Ω, wet-sponge type direct-current holiday detector
or equivalent method with an automated holiday counting system to determine the acceptability of the epoxy-coated steel
reinforcing bars prior to shipment.
8.2.2 If in-line detector or equivalent method is inoperable or unavailable, an off-line holiday detector or handheld detector shall
be permitted provided that 100 % of the epoxy-coated steel reinforcing bars are tested and all holiday counts are recorded.
NOTE 9—Handheld holiday detector checks should be performed each production day to verify the accuracy of the in-line system. Handheld holiday
detectors offer a reliable way to correlate data obtained from the in-line holiday detector and automated counting system.
8.2.3 On average, there shall not be more than 3 holidays per metre [one holiday per foot] on a coated steel reinforcing bar. The
average applies to the full production length of a bar.
8.2.4 A wetting agent shall be used in accordance with Test Methods G62 in the inspection for holidays on the coated steel
reinforcing bars.
8.3 Coating Flexibility:
8.3.1 The coating flexibility shall be evaluated by bending production coated steel reinforcing bars at a uniform rate around a
mandrel of specified size within a maximum specified time period as prescribed in Table 1. The two longitudinal ribs shall be
placed in a plane perpendicular to the mandrel radius. The test specimens shall be between 6868 °F and 86°F [2086 °F [20 °C and
30°C].30 °C].
8.3.2 Cracking or disbonding of the coating on the outside radius of the bent bar visible to a person with normal or corrected vision
shall be considered cause for rejection of the coated steel reinforcing bars represented by the bend test sample.
NOTE 10—The qualification requirements for coating flexibility (see A1.3.6.1) prescribe bending a No. 6 [No. 19] deformed bar around a 6-in. [150-mm]
diameter mandrel. The bend test requirements in Table 1 for evaluating the coating flexibility of production-coated steel reinforcing bars, for bar sizes
A775/A775M − 22
TABLE 1 Bend Test Requirements
A615, A706, A615M, A706M,
A996, or A1035 A996M, or A1035M
Bend
Time to
Mandrel Mandrel Angle
Bar Bar Comple-
Diameter, Diameter, (After
No. No. tion max,
A A
in. mm Rebound,
s
degrees)
3 3 10 75 180 15
4 4 13 100 180 15
5 5 16 125 180 15
6 6 19 150 180 15
7 7 22 175 180 45
8 8 25 200 180 45
9 9 29 230 180 45
10 10 32 250 180 45
11 11 36 280 180 45
14 17 43 430 90 45
18 23 57 580 90 45
A
Mandrel diameters specified for similar size (shown on the same line) inch-pound
and metric bars may be interchanged.
Nos. 3 to 8 [Nos. 10 to 25], are not compatible with fabrication bending practices. Finished bend diameters for bar sizes Nos. 3 to 8 [Nos. 10 to 25] used
in actual construction are smaller than the mandrel diameters in Table 1. Thus, the finished bends of production-coated bars, particularly the smaller bar
sizes used for stirrups and ties, should be examined closely for hairline cracking on the outside radius of the bent bar. If hairline cracking is present, it
should be repaired with patching material.
8.3.3 A test in which fracture or partial failure of the steel reinforcing bar, or cracking or disbonding caused by imperfections in
the bar surface visible after performing the bend test occurs, shall be considered an invalid test and the test shall be repeated on
a new specimen.
8.4 The requirements for coated steel reinforcing bars shall be met at the manufacturer’s plant prior to shipment.
9. Number of Tests
9.1 The purchaser shall have the option to specify the sampling and test schedule for the number and frequency of tests for coating
thickness, continuity, and flexibility.
9.2 If the number and frequency of tests are not specified by the purchaser the following apply:
9.2.1 Tests for coating thickness shall be made on a minimum of two bars of each size every two production hours,
9.2.2 Bend tests for coating flexibility shall be conducted on at least one bar of each size every four production hours, and
9.2.3 Random tests shall be made for coating continuity.
10. Retests
10.1 If the specimen for coating thickness or flexibility fails to meet the specified requirements, two retests on random samples
shall be conducted for each failed test. If the results of both retests meet the specified requirements, the coated steel reinforcing
bars represented by the samples shall be accepted.
11. Permissible Amount of Damaged Coating and Repair of Damaged Coating
11.1 The maximum amount of repaired damaged coating shall not exceed 1 % of the total surface area in each 1-ft [0.3 m] of the
bar. This limit on repaired damaged coating shall not include sheared or cut ends that are coated with patching material (see 11.4).
11.2 All damaged coating due to fabrication and handling (to the point of shipment to the job-site) shall be repaired with patching
material conforming to Annex A2.
A775/A775M − 22
NOTE 11—If the amount of repaired damaged coating in any 1-ft [0.3-m] length of a coated bar, exceeds 1 %, that section should be removed from the
coated steel reinforcing bar and discarded. In patching damaged coating , care should be taken not to apply the patching material over an excessive area
of the intact coating during the repair process. Too large an area of thick patching material especially on smaller-size reinforcing bars is likely to cause
a reduction in bond strength of the bars to concrete.
11.3 Repaired areas shall have a minimum coating thickness of 7 mils [175 μm].
11.4 When coated bars are sheared, saw-cut, or cut by other means during the fabrication process, the cut ends shall be coated
with patching material. Coated steel reinforcing bars shall not be flame cut.
11.5 Repair of damaged coating shall be performed in accordance with the patching material manufacturer’s written
recommendations.
12. Inspection
12.1 Inspection of the epoxy-coated steel reinforcing bars shall be agreed upon between the purchaser and the manufacturer as
part of the purchase order or contract.
13. Rejection
13.1 Coated steel reinforcing bars represented by test specimens that do not meet the requirements of this specification shall be
rejected and marked with a contrasting color paint or other suitable identification. At the manufacturer’s option, the affected lot
shall be replaced or, alternatively, stripped of coating, recleaned, recoated, and resubmitted for acceptance testing in accordance
with the requirements of this specification.
NOTE 12—If the coating is not to be stripped from the rejected steel reinforcing bars, the bars should be scrapped or with the purchaser’s approval used
as uncoated steel reinforcing bars.
14. Certification
14.1 The purchaser shall be furnished with, at the time of shipment, written certification that samples representing each lot of
coated steel reinforcing bars have been either tested or inspected as directed in this specification and the requirements have been
met. When specified in the purchase order or contract, a report of the test results shall be furnished.
14.2 A Material Test Report, Certificate of Inspection, or similar document printed from or used in electronic form from an
electronic data interchange (EDI) transmission shall be regarded as having the same validity as a counterpart printed in the
certifier’s facility. The content of the EDI transmitted document must meet the requirements of the invoked ASTM standard(s) and
conform to any EDI agreement between the purchaser and the supplier. Notwithstanding the absence of a signature, the
organization submitting the EDI transmission is responsible for the content of the report.
NOTE 13—The industry definition invoked here is: EDI is the computer-to-computer exchange of business information in a standard format such as ANSI
ASC X12.
15. Handling and Identification
15.1 All systems for handling coated steel reinforcing bars shall have padded contact areas. All bundling bands shall be padded
or suitable banding shall be used to prevent damage to the coating. All bundles of coated steel reinforcing bars shall be lifted with
a strong back, spreader bar, multiple supports, or a platform bridge to prevent bar-to-bar abrasion from sags in the bundles of coated
steel reinforcing bars. The bars or bundles shall not be dropped or dragged.
15.2 If circumstances require storing coated steel reinforcing bars outdoors for more than two months, protective storage measures
shall be implemented to protect the material from sunlight, salt spray and weather exposure. If the manufacturer stores coated steel
reinforcing bars outdoors without protective covering, the date on which the coated bars are placed outdoors shall be recorded on
the identification tag on the bundled steel. Coated steel reinforcing bars, whether individual bars or bundles of bars, or both, shall
be covered with opaque polyethylene sheeting or other suitable opaque protective material. For stacked bundles, the protective
covering shall be draped around the perimeter of the stack. The covering shall be secured adequately, and allow for air circulation
around the bars to minimize condensation under the covering.
A775/A775M − 22
15.3 Coated steel reinforcing bars, whether individual bars or bundles of bars, or both, shall be stored off the ground on protective
cribbing.
15.4 The identification of all steel reinforcing bars shall be maintained throughout the coating and fabrication processes to the
point of shipment.
16. Keywords
16.1 coating requirements; concrete reinforcement; corrosion resistance; epoxy coating; steel bars
ANNEXES
(Mandatory Information)
A1. REQUIREMENTS FOR ORGANIC COATINGS FOR STEEL REINFORCING BARS
A1.1 Powder Coatings
A1.1.1 This annex covers qualification requirements for barrier organic coatings for protecting steel reinforcing bars from
corrosion.
A1.1.2 The powder coating shall be of organic composition except for the pigment which may be inorganic if used.
A1.2 Test Materials
A1.2.1 A 1-lb [0.5-kg] sample of the powder coating with its generic description and its infrared spectrum shall be submitted to
the testing agency. The infrared spectrum shall be obtained with Fourier Transform Infrared Spectroscopy (FTIR) using Guide
E2937. The spectrum and generic description shall become an integral part of the qualification test report.
NOTE A1.1—The infrared spectrum uniquely identifies the powder sample.
A1.2.2 A sample of patching material conforming to Annex A2 shall be submitted to the testing agency. The product name and
a description of the patching material shall be given in the test report.
A775/A775M − 22
A1.2.3 Test Specimens:
A1.2.3.1 The following specimens shall be submitted as a minimum for test:
(1) Fourteen 4-ft [1.2-m] long No. 6, Grade 60 [No. 19, Grade 420] deformed steel reinforcing bars, with a coating thickness
of 77 mils to 12 mils [175[175 μm to 300 μm],
(2) Six uncoated and uncleaned No. 6 [No. 19] steel reinforcing bars, 4-ft [1.2-m] long, and from the same lot of steel as the
coated bars,
(3) Four 44 in. by 44 in. by 0.05 in. [100[100 mm by 100100 mm by 1.3 mm] steel plates with center holes for Taber abrasers
coated to a thickness of 1010 mils 6 2 mils [250[250 μm 6 50 μm].
(4) Four free films of coating material with a thickness of 77 mils to 9 mils [175[175 μm to 225 μm]. The films shall be at
least 44 in. by 4 in. [100[100 mm by 100 mm].
(5) Fourteen coated No. 6 [No. 19] steel reinforcing bars, 10-in. [0.25-m] long, coated to a thickness of 77 mils to 12 mils
[175[175 μm to 300 μm]. The coated steel reinforcing bars shall have their ends sealed with patching material.
A1.2.3.2 Steel reinforcing bars with a nominal diameter within 60.04 in. [61 mm] of No. 6 [No. 19] bars shall be acceptable for
qualification testing.
A1.2.3.3 The coating on the bars and films tested shall be free of holes, voids, contamination, cracks and damaged areas. The
coated bars shall be checked for holidays using a 67.5-V, 80 000-Ω, wet-sponge type dc holiday detector in accordance with Test
Methods G62. The total number of holidays found on the bar specimens tested shall be reported.
A1.2.3.4 Coating thickness measurements shall be made in accordance with 8.1.
A1.2.3.5 The manufacturer shall specify the method and grade of metal surface preparation and the coating application procedures
for the test specimens and for contract production of coated steel reinforcing bars. These procedures shall be listed in the test report.
NOTE A1.2—Production-coated steel reinforcing bars will be required to be manufactured in the same manner as the qualification bars. Therefore, it is
necessary that the qualification bars be prepared in the manner proposed for production. Variations in the critical preparation, thermal treatment, and
coating procedures known to be allowable without a comp
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