COMMITTEE ON MATERIALS AND PAVEMENTS

Tech Subcommittee 4f Mid-Year Meeting 2020 Page 1 of 6

COMMITTEE ON MATERIALS AND PAVEMENTS

Meeting (Annual or Mid-Year) Mid-Year Date Friday, November 20, 2020 Scheduled Time 11:00 a.m. – 12:00 p.m. (EST) Technical Subcommittee & Name 4f – Metals Chair Name and (State) Merrill Zwanka (SC) Vice Chair Name and (State) Steven Ingram (AL) Research Liaison Name and (State) N/A

I. Introduction and Housekeeping

II. Call to Order and Opening Remarks

A. Brief Summary of Activities Group 2 COMP ballot – had one concurrent ballot and six reconfirmation ballots.

III. Roll Call of Voting Members

Present Member Name State Present Member Name State ☒ Merrill Zwanka (Chair) SC ☒ Brett Trautman MO ☒ Steven Ingram (Vice Chair) AL ☒ Changlin Pan NV ☐ Michael San Angelo AK ☒ Kenny Seward OK ☐ Keith Hoffman CA ☐ Anne Holt ON ☒ Robert Lauzon (Jon Boardman

proxy) CT ☒ Timothy Ramirez PA

☐ Tim McCullough FL ☒ Danny Lane (Mike Doran proxy)

TN

☒ Monica Flournoy (&Peter Wu) GA ☒ John Schuler VA ☐ Brian Pfeifer IL ☐ Mladen Gagulic VT ☒ Richard Barezinsky KS ☐ Ron Stanevich WV ☒ Joseph Stillwell ME ☐

Quorum Rules Met? Annual Meeting: Simple majority of voting members (☒y/ ☐n) | Mid-Year Meeting: Voting members present (☐y/ ☐n)

A. Review of Membership

IV. Approval of Technical Subcommittee Minutes

July 30, 2020 Web Meeting - Attachment A

Motion to accept meeting minutes as written OK; MO seconds; no further discussion.

V. Old Business

A. Draft standard under review 1. TP XXX-XX Mechanically Spliced Reinforcement Bars

a. Started as NCHRP 12-105 b. Alaska reviewing draft – Attachment B c. Follow-up email in September: Alaska planned to get with CALTRANS and FHWA in October

concerning testing capabilities for larger bars. There was a high rate of fracture during testing of larger bars indicated in the NCHRP report. Will be updating us on this matter.


B. July 1, 2020 request to modify M 329, Stainless Clad Deformed and Plain Round Steel Bars for Concrete Reinforcement

1. Notified requestor that TS4f will not pursue modification at this time.

C. COMP Ballot Items (Include any ASTM changes/equivalencies, including ASTM standards’ revision years.) COMP Ballot # Standard

Results (neg/affirm) Comments/Negatives Action

10 M 31 Passed Concurrent Ballot. Attachment C. Michigan Comment: Affirmative, but would like to call attention to an apparent conflict between subsections 1.2 and 20.3.3. How can a bar meet Type S and W, when they are defined in 1.2 and dependent on a carbon content range that does not overlap? I may be missing something.

Ballot item had all affirmative votes. Contacted Michigan to clarify the wording in the subsections. Proceed with publication. Working to harmonize A615 and A706. S bar and W bars should be separate. George Miljus noted that the revisions look good and that ASTM may revise based on AASHTO’s clarifications. Continue to move this into publication and keep this issue in mind.

D. Technical Subcommittee Ballots TS Ballot # Standard


None M31 was a concurrent ballot item that passed TS and COMP.

E. Reconfirmation Ballots Reconf. Ballot # Standard


1 M 334 Passed No negatives or comments.

Reconfirm (old MMFX that got turned into M 334. Appendices were broken out into independent test methods which are all related to M 334)

2 T 372 Passed No negatives. Florida: If the purchaser is performing test that are critical to the evaluation of intergranular attack, the test results should be included. If the AASHTO group has seen enough test results to establish consistency in production methods and quality, then please disregard. Recommend changing Section 7 to read as follows: Section 7. Results from this test should be recorded and provided to the purchaser if requested.

Consider Florida comment for future edit. Reconfirm


3 T 373 Passed No negatives or comments.

Reconfirm

4 T 374 Passed No negatives. Vermont: Consider in section 7.1.1.7 include surface resistivity (T 358) value as equivalent alternative

Consider Vermont comment for future edit. Reconfirm

5 T 375 Passed No negatives. Florida: We may suggest a round robin to establish precision and bias in the instruments available to the market. Also, it may be beneficial to have a confirmatory test in case handheld XRF cannot be used to determine metal identification.

Consider Florida comment for future edit. Reconfirm

6 T 376 Passed No negatives. Vermont: Consider in section 4.9.1.7 and 4.9.3 include surface resistivity (T 358) value as equivalent alternative

Consider Vermont comment in future edit. Reconfirm

The chair is looking for a steward for these standards who is a technical expert. This is a great opportunity for your staff to get involved!!

F. Task Force Reports Task Force # Title Members Status/Update None

VI. New Business

A. AASHTO re:source/CCRL/NTPEP (Observations from assessments, as applicable.) There’s a rebar work plan revision being balloted through NTPEP right now

B. Presentation by Industry/Academia

C. Revisions/Work on Standards for Coming Year – List of Standards – Attachment D Standard # Title Task/Summary Assigned to M 54 Welded Deformed

Steel Bar Mats for Concrete Reinforcement

Review for ASTM A 184 equivalency.

M 102 Steel Forgings, Carbon and Alloy, For General Industrial Use


M 103 Steel Castings, Carbon, for General Application


M 105 Gray Iron Castings

Review internally. No ASTM equivalency.

M 285 Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe Service



Standard # Title Task/Summary Assigned to

M 292 Carbon Steel, Alloy Steel and Stainless Steel Nuts for Bolts for High-Pressure or High-Temperature Service, or Both


M 322 Rail-Steel and Axle-Steel Deformed Bars for Concrete Reinforcement


T 244 Mechanical Testing of Steel Products


T 372 Sensitivity of Stainless Steel to Intergranular Attack

Consider comments from October 2020 reconfirmation ballot.

T 374 Comparative Qualitative Corrosion Characterization of Uncoated Chromium-Alloyed Steel Bars Used in Concrete Reinforcement (Tombstone Test)


T 375 Identification of Iron-Based Alloy Steel Bars for Concrete Reinforcement or Dowels by Handheld X-Ray Fluorescence (XRF) Spectrometer


T 376 Macrocell Slab Chloride Threshold


D. Review of Stewardship List (List of subcommittee’s standards flagging those requiring action; include as separate attachment.)

E. Proposed New Standards 1.

F. NCHRP Issues

G. Correspondence, Calls, Meetings

H. Proposed New Task Forces (Include list of volunteers to lead and/or join TF.)

I. New TS Ballots 1.

VII. Open Discussion


A. MO noticed an issue in M 31 and there appears to be a reference error section 13.1 refers to annex A9 of T244 but there is no A9 – it’s not Annex I. That would be an editorial change and will get over to pubs.

B.

VIII. Adjourn

TS Meeting Summary

Meeting Summary Items Approved by the TS for Ballot (Include reconfirmations.)

Standard Designation Summary of Changes Proposed Ballot Type

☐TS ☐COMP ☐CONCURRENT ☐TS ☐COMP ☐CONCURRENT ☐TS ☐COMP ☐CONCURRENT

☐TS ☐COMP ☐CONCURRENT



☐TS ☐COMP ☐CONCURRENT ☐TS ☐COMP ☐CONCURRENT



☐TS ☐COMP ☐CONCURRENT New Task Forces Formed Task Force Name Summary of Task TF Member Names and (States)

Research Proposals (Include number/title/states interested.)

Other Action Items Change M 31 with reference to Annex 9 which should be Annex I

Attendance:

Rick Barezinsky [email protected]

David Black [email protected]

Jonathan Boardman [email protected]

Mark Brum [email protected]


Jeff De Vries [email protected]

Michael Doran [email protected]

Mark Felag [email protected]

Monica Flournoy [email protected]

Georgene Geary [email protected]

Steven Ingram [email protected]

Joseph Kerstetter [email protected]

Dean Krouse [email protected]

Katheryn Malusky [email protected]

Ryan McBroom [email protected]

George Miljus [email protected]

CHARLIE PAN [email protected]

Steve Paiva [email protected]

Timothy Ramirez [email protected]

John Schuler [email protected]

Kenny Seward [email protected]

Temple Short [email protected]

Mike Stelzer [email protected]

Joe Stilwell [email protected]

Brett Trautman [email protected]

Samuel Wade [email protected]

Todd Whittington [email protected]

Peter Wu [email protected]

Merrill Zwanka [email protected]

Greg uherek [email protected]

ASTM / ACI Rebar ChangesGeorge MiljusASTM A01.05.01 Section Chairman, Reinforcing Steel

ASTM A615 Rebar Changes

Harmonize (match) the tensile strengths of Grades 60 and 80 for ASTM A615 and A706

Add a minimum T/Y (tensile/yield) ratio of 1.10 to all A615 Grades

These changes for ASTM A615-20 just published in April, 2020

ACI 318 Building Code Committee balloted and passed these updated requirements for reinforcing steel for general use.

A615 (2018) vs. ‘New’ A615 (2020)

ASTM A615 (2018)

Grade 40 60 80 100

Yield (ksi min) 40 60 80 100

Tensile (ksi min) 60 90 105 115

Elongation (%) 12 9 7 7

ASTM A615 (2020)

Grade 40 60 80 100

Yield ( ksi min) 40 60 80 100


Elongation (%) 12 9 7 7

Why add a T/Y ratio to A615?

The primary reason for adding the specified T/Y (tensile/yield) ratio of 1.10 is to guarantee some minimum strain hardening beyond the yield strength for building safety.

A secondary reason is to prevent the misconception that a T/Y ratio is implied based on the specification tensile and yield minimums. A T/Y ratio is currently neither intended or implied.

Why ‘Harmonize’ GR60 for A615 and A706?

The primary reason for matching the tensile requirements for A615 and A706 is to prevent undesired over-strength for dual-grade product.

A secondary reason for this alignment is that the ACI 318 code currently allows A706 Grade 60 for general use, but it has been misinterpreted in the market that the 90 ksi minimum is required for gravity loads utilizing A706 Grade 60.

Strong desire for a dual-grade product that could be used for DOT work as well as ACI 318 Building Code construction. With the change, ALL A706 GR60 will meet the specifications A615 GR60

A615 (current) vs. A706 (current) –Now GR60 and GR80 are aligned

A615-20

Grade 40 60 80 100

Yield ( ksi min) 40 60 80 100


Elongation 12 9 7 7

A706-16

Grade 60 80

Yield ( ksi min) 60 80

Tensile (ksi min) 80 100

Elongation 14 12

AASHTO M 31 Type S vs. ASTM A615

M 31 Type S - Current

Grade 40 60 75 80

Yield (min) 40 60 75 80

Tensile (min) 60 90 100 105

Elongation 12 9 7 7

ASTM A615 – Current (2020)

Grade 40 60 80 100

Yield (min) 40 60 80 100

Tensile (min) 60 80 100 115

Elongation 12 9 7 7

AASHTO M 31 Type W vs. ASTM A706

M 31 Type W - Current

Grade 40 60 75 80

Yield (min) 40 60 75 80

Tensile (min) 60 90 100 105

Elongation 16 14 12 12

A706 – Current (2016)

Grade 60 80

Yield (min) 60 80

Tensile (min) 80 100

Elongation 14 12

Current ASTM A615 GR80 properties as they compare to the old GR75

Grade 75 80

Yield ( ksi min) 75 80

Tensile (ksi min) 100 100

Elongation 7 7

Why replace GR75 with GR80?

Two grades with essentially the same mechanical properties

Keeping two inventories of these two similar grades would be cost-prohibitive for steel producers, fabricators, and contractors.

Bar markings require that each grade be marked as such, preventing the substitution of in-stock product

The CRSI database shows that the vast majority of GR75 produced meets 80,000 psi yield strength.

ASTM A615-20 (Current)

ASTM A706-16 (Current)

Summary

These changes will benefit the entire steel reinforced concrete industry at large by improving harmonization between ASTM and ACI specifications and allowing producers and users to pursue more efficient dual-grade options.

Standard Method of Test for

Mechanically Spliced Steel Reinforcing Bars

AASHTO Designation: M T xxx-yy1

Technical SectionSubcommittee: No., Name4f, Metals

Release: Group n 2 (Month yyyyJune)

American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001

TS-no4f M T xxx-1 AASHTO

Standard Method of Test for

Mechanically Spliced Steel Reinforcing Bars

AASHTO Designation: M T xxx-yy Technical SectionSubcommittee: No., Name [with line break if needed to keep space around logo] 4f, Metals

Release: Group n 2 (Month yyyyJune)

1. SCOPE

1.1. These test methods cover monotonic, cyclic, and dynamic testing procedures for the determination of mechanical properties of mechanically spliced M 31, A 615 and A 706 Grade 60 steel reinforcing bars that are used in the plastic hinge region of ductile members, such as bridge columns subjected to moderate and high seismic loads.

1.2. In addition to satisfying the criteria specified in this document, mechanical splices shall meet the requirements for non-seismic loads.

1.3. The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capacity, calibration, and maintenance of the equipment used. Agencies that meet the criteria of R 18 are generally considered capable of competent and objective testing/sampling/inspection, etc. Users of this standard are cautioned that compliance with R 18 alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of R 18 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.

1.2.

2. REFERENCED STANDARDS

2.1. AASHTO Standards: M 31, Specification for Deformed and Plain Carbon and Low-Alloy Steel Bars for Concrete

Reinforcement R 18, Establishing and Implementing a Quality Management System for Construction

Materials Testing Laboratories T 244, Standard Method of Test for Mechanical Testing of Steel Products

2.2. ASTM Standards: ASTM A 370, Standard Test Methods and Definitions for Mechanical Testing of Steel

Products ASTM A 615, Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete

Reinforcement ASTM A 706, Standard Specification for Deformed and Plain Low-Alloy Steel Bars for

Concrete Reinforcement ASTM A 1034, Standard Test Methods for Testing Mechanical Splices for Steel Reinforcing

Bars

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Formatted: Font: (Default) Times New Roman

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ASTM E 4, Standard Practices for Force Verification of Testing Machines ASTM E 8, Standard Test Methods for Tension Testing of Metallic Materials ASTM E 83, Standard Practice for Verification and Classification of Extensometer Systems ASTM E 2309, Standard Practices for Verification of Displacement Measuring Systems and

Devices Used in Material Testing Machines

3. TERMINOLOGY

3.1. Definitions of Terms Specific to This Standard:

3.1.1. Bar Region–A length of the spliced bar outside the coupler region (Figure 1) that is utilized for the strain measurement of spliced bars.

Figure 1—Coupler and bar regions

3.1.2. Coupler–Device for joining reinforcing bars for the purpose of providing transfer of either axial compression or axial tension or both from one bar to the other. The terms “coupler” and “splice” are interchangeable in this document.

3.1.3. Coupler Region–A length consisting of the total length of the coupler (Lsp) plus one bar diameter (db ) on each end of the coupler (Figure 1).

3.1.4. Coupler Rigid Length Ratio (β)–A ratio that represents the rigidity of a coupler. Rigidity of a coupler depends on the anchoring mechanism of the coupler and includes the effect of coupler elongation, bar elongation inside the coupler, and the slippage of the spliced bars inside the coupler.

3.1.5. Fracture–Physical rupture or breaking of bars or couplers.

3.1.6. Lot–A lot includes 150 count, or fraction thereof, of the same type of either reinforcing bars or mechanical bar splice for each bar size and bar deformation pattern.

3.1.7. Mechanical Bar Splices–Mechanical devices that are used to connect two reinforcing bars. The term “coupler” is frequently used for mechanical bar splices.

3.1.8. Necking–The onset of nonuniform or localized plastic deformation, resulting in a localized reduction of cross-sectional area

3.1.9. Plastic Range–A strain range between the yield and the ultimate points in the stress-strain relationship of a reinforcing bar or splice.

3.1.10. Samples–Reinforcing bars from the same lot.


3.1.11. Seismic Splices–Couplers that are not longer than 15db and exhibit bar fracture outside the coupler region with a strength that is at least 95% of the tensile strength of a corresponding “unspliced specimen” as defined below. All the spliced test specimens shall meet these requirements to be considered as a “seismic splice.”

3.1.12. Spliced Specimen–A specimen including a coupler and two spliced bars connected to the coupler.

3.1.13. Strain–The ratio of the elongation of the test specimen within the initial gauge length to the initial gauge length, per ASTM E 6.

3.1.14. Stress–The ratio of the applied load to the sample nominal cross-section area, see ASTM E 6.

3.1.15. Ultimate Tensile Strength–Per ASTM E 6, the maximum tensile stress a mechanically spliced bar is capable of sustaining.

3.1.16. Ultimate Strain–The strain corresponding to the maximum tensile stress in a stress-strain relationship.

3.1.17. Unspliced Specimen–A single-bar specimen used to determine benchmark mechanical properties of bars.

4. SAFETY PRECAUTIONS

4.1 The test samples are heavy and may contain sharp edges or burrs. Sample fracture may involve brittle fractures and ejection of sample fragments. Use appropriate safety measures.

4.2 It is the responsibility of the user of this test method to establish appropriate safety practices and determine the applicability of regulatory limitations prior to use. Prior to handling, testing or disposing of any materials, testers must be knowledgeable about safe laboratory practices and personal protective apparel and equipment.

5. MATERIALS, TESTING APPARATUS AND OPERATIONS

5.1. Testing Machines–Tensile testing machines shall conform to the requirements of ASTM E 4. Components of testing machines such as grips, measurement devices, and calibration of the machines shall conform to the requirements of ASTM E 8 and ASTM A 370.

5.2 Displacement Measuring Devices–Displacement measuring devices such as dial indicators and LVDTs shall conform to the requirements of Class-A ASTM E 2309.

5.2.1 Extensometers–Extensometers used in strain measurement shall conform to the requirements of ASTM E 83. Use Class B2 or better extensometers.

5.2.2 Caliper–A calibrated caliper with an accuracy of 0.001 in. or better.

5.3 Samples–Each test sample shall conform to the following requirements:

5.3.1 Sample length: For No. 9 bars and smaller, sample length must be at least 5 ft. For No. 10 bars and larger, sample length must be at least 7.5 ft.

5.3.2 Spliced specimen length: The lab may shorten, machine, or otherwise alter the submitted sample length to meet the configuration of its testing equipment. The minimum length of the spliced specimen between the grips of the tensile testing machine shall be Lsp + 16db, where Lsp is the

Formatted: Font: Not Italic




coupler length, and db is the nominal bar diameter of the larger spliced bar. The center of the coupler shall be located at the center of the test specimen. The unspliced and spliced specimens for each test shall be taken from the same lot.

5.5.3 Alignment: The alignment along the test sample must be straight to within 0.5 in. along any 3 ft of the length of the sample.

MONOTONIC TEST

6. SAMPLING AND NUMBER OF SPECIMENS

6.1. Monotonic tensile testing of unspliced and spliced specimens is required for each bar size and shall be performed according to T 244 or ASTM A 370. Additional requirements for spliced specimens are referenced in ASTM A 1034. Test four samples for each lot.

7. UNSPLICED SPECIMEN - PROCEDURE

7.1 Apply an axial tensile load to the unspliced specimen to fracture. Follow ASTM E 8 and AASHTO T 244 speed testing guidelines.

7.2 A full stress-strain curve can be obtained using continuous measurement (e.g. 8-in. extensometer and data acquisition system) (Figure 2a) or discontinuous measurement (dial or digital indicators) (Figure 2b).

7.3 Steps for the discontinuous method are:

7.3.1 Measure the initial gauge length using a caliper. An 8-in. gauge length is recommended.

7.3.2 Mount the unspliced specimen in the tensile test machine.

7.3.3 Attach two displacement measuring devices so that their indicators are 180° apart.

7.3.4 Apply an axial stress of 30 ksi. Maintain this stress until a stable reading is obtained from both indicators. Record the two indicator readings then take the average of the two readings. Increase the stress to 90% the nominal yield strength and record the average of the two indicator readings.

7.3.5 After the two initial readings in the elastic rage, more frequent reading is needed to properly capture the plastic range of the stress-strain diagram. At least 10 data points are needed in the plastic range. The appropriate readings (force in the plastic range) may be obtained when the indicators show values corresponding to strains equal to 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, and 0.01 in./in. Readings with an interval of 0.01 in./in. should be continued until bar fractures.

7.3.6 Remove the displacement measuring devices.

7.3.7 Report the full-stress-strain curve for the unspliced specimen (Figure 3)

Note 1— For an unspliced specimen, the measurement is valid only when the bar fractures within the instrumented gauge length.




Commented [ZME1]: Plus or minus what tolerance?



Commented [ZME3]: Should this be 0.10?






(a) Unspliced Specimen – Continuous Reading (b) Unspliced Specimen – Discontinuous Reading

Figure 2—Test setup and minimum length requirements for unspliced specimens

Figure 3—Measured stress-strain diagram for unspliced specimens

8. SPLICED SPECIMEN – PROCEDURE

8.1 Apply an axial tensile load to the spliced specimen to fracture. Follow ASTM E 8 and AASHTO T 244 speed testing guidelines.

8.2 A full stress-strain curve can be obtained using continuous measurement (e.g. LVDT or coupler extensometer and data acquisition system) (Figure 4a), or discontinuous measurement (dial or digital indicators) (Figure 4b).

8.3 Steps for the discontinuous method are:

8.3.1 Measure the initial gauge length using a caliper. The gauge length shall be taken as Lcr = Lsp + 2αdb, where Alpha shall not exceed two. Alpha equal to 1.0 is used in Figure 4.

8.3.2 Mount the spliced specimen in the tensile test machine as shown in Figure 4b.

Grip

b2d

8 in.

2db

Exte

nsom

eter

Grip

2d

2db

b

Gau

ge 8 in.

Continuous Reading

u

f

sh

f

Stre

ss

ε

y

Discontinuous Reading

Strainε

u


8.3.3 Attach two displacement measuring devices so that their indicators are 180° apart.

8.3.4 Once the setup is complete, stress the smaller spliced specimen to 3 ksi in the bar then zero out both indicators.

8.3.5 Apply an axial stress of 30 ksi in the smaller spliced bar. Maintain this stress until a stable reading is obtained from both indicators. Record the two dial indicator readings then take the average of the two readings. Increase the stress to 90% the nominal yield strength and record the average of the two indicator readings.

8.3.6 After two initial readings in the elastic rage, more frequent reading is needed to properly capture the plastic range of the stress-strain diagram. At least 10 data points are needed in the plastic range. The appropriate readings (force in the plastic range) may be obtained when the indicators show values corresponding to strains equal to 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, and 0.055 in./in. Readings with an interval of 0.005 in./in. should be continued until bar fractures.

(a) Spliced Specimen – Continuous Reading (b) Spliced Specimen – Discontinuous Reading

Figure 4—Test setup and minimum length requirements for spliced specimens

8.4 Remove the displacement measuring devices.

8.5 Report the mode of failure (bar fracture, bar pullout, or coupler fracture) and the location of the failure.

8.6 Report the full-stress-strain curve for spliced specimen (Figure 5).











Figure 5—Measured stress-strain diagram for the spliced specimens

8.7 Superimpose the stress-strain curve of the spliced specimen with that measured for the unspliced specimen (Figure 6). Draw two vertical lines, one at the start of strain hardening (Line 1) and the other at the ultimate points of the stress-strain diagram for the spliced bar (Line 5). Draw additional three vertical lines between the two with equal spacing and determine the stresses (fi) and strains (𝜀𝜀𝑠𝑠𝑠𝑠

𝑖𝑖 ) at five points on the diagram, with the first and last being the yield and ultimate points. Using the stresses (fi), determine the associated strains on the stress-strain diagram for the unspliced bar (𝜀𝜀𝑠𝑠

𝑖𝑖 ). This will lead to five strain values each for the spliced and unspliced bars. Calculate the coupler rigid length ratio, βi, for each pair of strains:

𝛽𝛽𝑖𝑖 = (1 −𝜀𝜀𝑠𝑠𝑠𝑠 𝑖𝑖

𝜀𝜀𝑠𝑠 𝑖𝑖 )(

𝐿𝐿𝑐𝑐𝑐𝑐𝐿𝐿𝑠𝑠𝑠𝑠

) (1)

Calculate the coupler rigid length ratio, β, for spliced specimen as

𝛽𝛽 =1𝑁𝑁�

𝛽𝛽𝑖𝑖 (2)

where N is the number of the data points. Round up the calculated coupler rigid length ratio to the

nearest 0.05 (e.g. 0.76 will be 0.80). The minimum and maximum calculated coupler rigid length ratios shall be 0.5 and 1.0, respectively (0.5 ≤ 𝛽𝛽 ≤ 1.0).

u

f

ysp

sp

Strainε

u

ε spsh

f

Stre

ss

ε

y

sp

sp


Figure 6—Calculation of coupler rigid length ratio based on stress-strain relationships

8.8 Report all 𝛽𝛽𝑖𝑖 and 𝛽𝛽. The design value for the coupler rigid length ratio may be taken as the average for all the test specimens.

Note 2— When testing facility allows continuous measurement with multiple channels using a data acquisition system, the stress-strain curve for the unspliced bar may be measured during the testing of a spliced sample. A pair of extensometers, one for each potential bar fracture zone outside the coupler region, may be used for this purpose. In this case, the ratio of the coupler region strain to the bar region strain can be directly calculated using the continuous dataset but utilizing the strain data for the extensometer in which the spliced bar fractures. Subsequently, the coupler rigid length ratio can be calculated according to Equation 1 then Equation 2. All requirements such as number of specimens, testing device accuracy, testing speeds, results, etc., remain the same as those discussed in Sections 6 to 8.

Note 3— When the yield stress in the spliced and unspliced specimens is different due to scatter in data, use the strain at the start of strain hardening of the unspliced bar for 𝜀𝜀𝑠𝑠

1 .

Note 4— When the ultimate tensile strength in the spliced and unspliced specimens is different due to scatter in data, use the ultimate strain of the unspliced bar for 𝜀𝜀𝑠𝑠

5.

Note 5— Ignore any point at which the stress in the spliced bar exceeds the ultimate tensile strength of the unspliced bar. This could occur due to data scatter.

8.9 Report whether or not the coupler meets the requirements of the “seismic splice” under monotonic loading

Note 6— A coupler is not qualified as a seismic splice if the failure mode in any of the four samples is bar fracture inside coupler, bar pullout, or coupler failure. For a spliced specimen, the strain measurement is valid only when the bar fractures outside the coupler region and outside the grip. When bar ruptures outside the coupler but within the coupler region (defined as the coupler length plus one bar diameter on each side), another spliced specimen may be tested solely to obtain reliable strain data. Report measured data and mode of failure for all five specimens.

Line

1

Line

2

Line

3

Line

4

Line

5

Formatted: Indent: Left: 1"



CYCLIC TEST

9. DESCRIPTION, SAMPLING AND NUMBER OF SPECIMENS

9.1 Cyclic tensile testing of spliced specimens is required for product verification of a new coupler or that which has not been tested according to the cyclic test procedure presented herein, and that is intended to be used in the plastic hinge region of ductile members, such as bridge columns, see ASTM A 1034 for further information.

9.2 Test four samples for each lot. Continuous measurement as explained in the previous section is recommended. A cycle in this document refers to a half-cycle and consists of applying tensile axial loading to the specimen to a target stress or strain and unloading to zero force (or a small tensile forces).

10. PROCEDURE

10.1 Cyclically load the spliced specimen at 10%, 30%, 50%, 70%, 80%, 90%, and 100% of the ultimate tensile strength (fu) of the spliced bar. Repeat each cycle of loading four times. Use a constant rate of prior-to-yielding or post-yielding specified in ASTM E 8.

Note 7— To avoid buckling of the test sample under accidental compressive loads, the tensile stress on the unloading branch of each cycle does not need to be less than 3 ksi in the larger of the spliced bar.

Note 8— The measured stress-strain data from a spliced specimen with the same coupler type, bar size, and reinforcement properties tested under monotonic loading may be used to determine the strains corresponding to the target cyclic stresses.

10.2 Report the mode of failure (bar fracture, bar pullout, or coupler fracture) and whether the fracture occurred inside or outside the coupler region. If continuous measurement is utilized, report the cyclic stress-strain graphs for the spliced specimens.

10.3 Report whether or not the coupler meets the requirements of the “seismic splice” under cyclic loading.

DYNAMIC TEST

11. DESCRIPTION, SAMPLING AND NUMBER OF SPECIMENS

11.1 Dynamic tensile testing of spliced specimens is required for product verification of a new coupler or that which has not been tested according to the dynamic test procedure presented herein, and that is intended to be used in the plastic hinge region of ductile members, such as bridge columns, see ASTM A 1034 for further information.

11.2 Test four samples for each lot. Continuous measurement as explained in previous sections is recommended


Commented [ZME7]: Should this be 3.0? What plus and minus tolerances?



12. PROCEDURE

12.1 Load the spliced specimen with a strain rate of 30,000 micro-strain/sec (3.0%/sec) to fracture. The strain rate may be converted to the machine head displacement rate using a length which is equal to the grip-to-grip clear distance minus 𝛽𝛽𝐿𝐿𝑠𝑠𝑠𝑠. An error of up to 25% between the target and the achieved strain or displacement rate shall be allowed.

12.2 Report the mode of failure (bar fracture, bar pullout, or coupler fracture) and whether the fracture occurred inside or outside the coupler region. If continuous measurement is utilized, report the stress-strain graphs for the spliced specimens.

12.3 Report whether or not the coupler meets the requirements of the “seismic splice” under dynamic loading.

13. REPORT

13.1 A “Test Report” shall be developed including the items specified in the present document for each loading type. See ASTM A 1034 for additional requirements needed for the test report.

14. KEYWORDS

14.1. Mechanical splices; reinforcing bar testing; plastic hinge region.

APPENDIX

(Nonmandatory Information)

X1. EXAMPLES OF STRAIN MEASURING DEVICES

X1.1. Photographs of different strain measuring devices for mechanical bar splices are presented in Figure X1.1.

Commented [ZME8]: What plus or minus tolerances?


(a) Device with dial indicators (California Test 670)

(b) Device with extensometer

(c) Device with two LVDTs (d) Device with coupler extensometer

Figure X1.1—Different strain measuring devices for mechanical bar splices

Standard Specification for

Deformed and Plain Carbon and Low-Alloy Steel Bars for Concrete Reinforcement

AASHTO Designation: M 31M/M 31-191211

Technical Subcommittee: 4f, Metals

Release: Group 2 (June)

ASTM Designation: A615/A615M-1620

American Association of State Highway and Transportation Officials 555 12th Street NW, Suite 1000 Washington, D.C. 20004

TS-4f M 31M/M 31-1 AASHTO

Standard Specification for

Deformed and Plain Carbon and Low-Alloy Steel Bars for Concrete Reinforcement

AASHTO Designation: M 31M/M 31-19211 Technical Subcommittee: 4f, Metals Release: Group 2 (June) ASTM Designation: A615/A615M-1620

1. SCOPE

1.1. This specification covers deformed and plain carbon and low-alloy steel concrete reinforcement bars in cut lengths or coils. Steel bars containing alloy additions, such as with the AISI and SAE series of alloy steels, are permitted if the resulting product meets all the other requirements of this specification. The standard sizes and dimensions of deformed bars and their number designations shall be those listed in Table 1. The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this specification.

1.2. Bars are of four three minimum yield strength levels: namely, 280 MPa [40,000 psi], 420 MPa [60,000 psi], 520 MPa [75,000 psi], and 550 MPa [80,000 psi], designated as Grade 280 [40], Grade 420 [60], Grade 520 [75], and Grade 550 [80], respectively. Bars that have carbon contents limited to 0.30 percent or less, and that meet the carbon requirements of this specification, shall be designated as Type W. Bars that have carbon contents greater than 0.30 percent shall be designated as Type S..

1.3. Hot-rolled plain rounds, in sizes up to and including 63.5 mm [21/2 in.] in diameter in coils or cut lengths, when specified for dowels, spirals, and structural ties or supports, shall be furnished under this specification in Grade 280 [40], Grade 420 [60], Grade 520 [75], and Grade 550 [80]. For ductility properties (elongation and bending), test provisions of the nearest smaller nominal diameter deformed bar size shall apply. Requirements providing for deformations and marking shall not be applicable.

1.4. Welding of the material in this specification should be approached with caution since no specific provisions have been included to enhance its weldability. When the steel is to be welded, a welding procedure suitable for the chemical composition and intended use or service should be used (Note 1). Note 1—The use of the latest edition of ANSI/AWS D1.4 is recommended for welding reinforcing bars. This document describes the proper selection of the filler metals and preheat/interpass temperatures, as well as performance and procedure qualification requirements.


Table 1—Deformed Bar Designation Numbers, Nominal Masses, Nominal Dimensions, and Deformation Requirements

Nominal Dimensionsa Deformation Requirements, mm [in.]

Bar Designation

No.b

Nominal Mass,

kg/m [lb/ft] Diameter, mm [in.]

Cross- Sectional

Area, mm2 [in.2]

Perimeter, in. [mm]

Maximum Average Spacing

Minimum Average Height

Maximum Gap (Chord of 12.5%

of Nominal Perimeter)

10 [3] 0.560 [0.376] 9.5 [0.375] 71 [0.11] 29.9 [1.178] 6.7 [0.262] 0.38 [0.015] 3.6 [0.143] 13 [4] 0.994 [0.668] 12.7 [0.500] 129 [0.20] 39.9 [1. 571] 8.9 [0.350] 0.51 [0.020] 4.9 [0.191] 16 [5] 1.552 [1.043] 15.9 [0.625] 199 [0.31] 49.9 [1.963] 11.1 [0.437] 0.71 [0.028] 6.1 [0.239] 19 [6] 2.235 [1.502] 19.1 [0.750] 284 [0.44] 59.8 [2.356] 13.3 [0.525] 0.97 [0.038] 7.3 [0.286] 22 [7] 3.042 [2.044] 22.2 [0.875] 387 [0.60] 69.8 [2.749] 15.5 [0.612] 1.12 [0.044] 8.5 [0.334] 25 [8] 3.973 [2.670] 25.4 [1.000] 510 [0.79] 79.8 [3.142] 17.8 [0.700] 1.27 [0.050] 9.7 [0.383] 29 [9] 5.060 [3.400] 28.7 [1.128] 645 [1.00] 90.0 [3.544] 20.1 [0.790] 1.42 [0.056] 10.9 [0.431] 32 [10] 6.404 [4.303] 32.3 [1.270] 819 [1.27] 101.3 [3.990] 22.6 [0.889] 1.63 [0.064] 12.4 [0.487] 36 [11] 7.907 [5.313] 35.8 [1.410] 1006 [1.56] 112.5 [4.430] 25.1 [0.987] 1.80 [0.071] 13.7 [0.540] 43 [14] 11.38 [7.65] 43.0 [1.693] 1452 [2.25] 135.1 [5.32] 30.1 [1.185] 2.16 [0.085] 16.5 [0.648] 57 [18] 20.24 [13.60] 57.3 [2.257] 2581 [4.00] 180.1 [7.09] 40.1 [1.58] 2.59 [0.102] 21.9 [0.864] 64 [20] 24.84 [16.69] 63.5 [2.500] 3167 [4.91] 199.5 [7.85] 44.5 [1.75] 2.86 [0.113] 24.3 [0.957]

a The nominal dimensions of a deformed bar are equivalent to those of a plain round bar having the same mass per meter as the deformed bar. [The nominal dimensions of a deformed bar are equivalent to those of a plain round bar having the same weight per foot as the deformed bar.]

b Bar numbers are based on the number of eighths of an inch included in the nominal diameter of the bars. [Bar designation numbers approximate the number of millimeters of the nominal diameter of the bar.]

1.5. This specification is applicable for orders in either SI units (M 31M) or in inch-pound units (M 31). SI units and inch-pound units are not necessarily equivalent; therefore, each system must be used independently of the other. Combining values from the two systems may result in non-conformance with the specification. Inch-pound units are shown in brackets in the text for clarity, but they are the applicable values when the material is ordered to M 31.

1.6. 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 and health practices and determine the applicability of regulatory limitations prior to use.

2. REFERENCED DOCUMENTS

2.1. AASHTO Standards: T 244, Mechanical Testing of Steel Products T 285, Bend Test for Bars for Concrete Reinforcement

2.2. ASTM Standards: A6/A6M, Standard Specification for General Requirements for Rolled Structural Steel Bars,

Plates, Shapes, and Sheet Piling A510/A510M, Standard Specification for General Requirements for Wire Rods and Coarse

Round Wire, Carbon Steel, and Alloy Steel A700, Standard Guide for Packaging, Marking, and Loading Methods for Steel Products for

Shipment A706/A706M, Standard Specification for Deformed and Plain Low-Alloy Steel Bars for

Concrete Reinforcement A751, Standard Test Methods, Practices, and Terminology for Chemical Analysis of Steel

Products E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance

with Specifications


2.3. Military Standards: MIL-STD-129, Marking for Shipment and Storage MIL-STD-163, Steel Mill Products Preparation for Shipment and Storage

2.4. Federal Standard: Fed. Std. No. 123, Marking for Shipment (Civil Agencies)

2.5. AWS Standard: ANSI/AWS D1.4, Structural Welding Code—Reinforcing Steel

3. TERMINOLOGY

3.1. Description of Terms Specific to This Standard:

3.1.1. deformations—transverse protrusions on a deformed bar.

3.1.2. deformed bar—steel bar with protrusions; a bar that is intended for use as reinforcement in reinforced concrete construction.

3.1.2.1. Discussion—The surface of the bar is provided with lugs or protrusions that inhibit longitudinal movement of the bar relative to the concrete surrounding the bar in such construction. The lugs or protrusions conform to the provisions of this specification.

3.1.3. plain bar—steel bar without protrusions.

3.1.4. rib—longitudinal protrusion on a deformed bar.

4. ORDERING INFORMATION

4.1. Orders for carbon or low-alloy steel bars for concrete reinforcement under this specification shall contain the following information:

4.1.1. Quantity (mass) [weight],

4.1.2. Deformed and plain,

4.1.3. Bar designation number (size) of deformed bars, or diameter of plain bars,

4.1.4. Cut length or coils,

4.1.5. Grade,

4.1.6. Type S or Type W, and

4.1.7. AASHTO designation 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. Certified mill test reports for Type S bars, if desired (see Section 19);

4.2.2. Require bars in each bundle to be supplied from a single heat (see Section 19.1);


4.2.3. Special packaging or marking requirements (see Section 21);

4.2.4. Domestic origin; and

4.2.5. Other special requirements, if any.

5. MATERIAL AND MANUFACTURE

5.1. The bars shall be rolled from properly identified heats of mold cast or strand cast steel using any commercially accepted steelmaking process. The producer shall have the option to manufacture the bars either by hot rolling, or thermal mechanical processing, or quench and tempering, whereby the selected process enables the requirements of this specification to be satisfied.

6. CHEMICAL REQUIREMENTS

6.1. The chemical analysis of each heat of steel shall be determined in accordance with ASTM A751. The manufacturer shall perform the analysis on test samples taken preferably during the pouring of the heat.

6.1.1. For Type S bars, the percentages of carbon, manganese, phosphorus, and sulfur shall be determined. The phosphorus content thus determined shall not exceed 0.06 percent.

6.1.1.1. A chemical verification analysis may be made by the purchaser from finished Type S bars. The phosphorus content determined shall not exceed 0.075 percent.

6.1.2. For Type W bars, the percentages of carbon, manganese, phosphorus, sulfur, and silicon shall be determined and reported. If any other alloying elements are intentionally added to the heat to produce the required properties for Type W bars, such as copper, nickel, chromium, molybdenum, vanadium, niobium, titanium, or boron, they shall also be determined.

6.1.2.1. The maximum heat and verification (check) analysis allowable percentages for carbon, manganese, phosphorus, sulfur and silicon are as shown in Table 2.

Table 2—Chemical Requirements, SI Units Element Heat Analysis, % max Verification Analysis, % max

Carbon 0.30 0.33 Manganese 1.50 1.56 Phosphorus 0.035 0.044 Sulfur 0.045 0.053 Silicon 0.50 0.55

6.1.3. For Type W bars, the heat analysis shall be such that the carbon equivalent (C.E.) does not exceed 0.55 percent, as calculated by the following formula:

% Mn % Cu % Ni % Cr % Mo % VC.E. % C6 40 20 10 50 10

= + + + + − −

7. REQUIREMENTS FOR DEFORMATIONS

7.1. Deformations shall be spaced along the bar at substantially uniform distances. The deformations on opposite sides of the bar shall be similar in size, shape, and pattern.


7.2. The deformations shall be placed with respect to the axis of the bar so that the included angle is not less than 45 degrees. Where the line of deformations forms an included angle with the axis of the bar from 45 to 70 degrees inclusive, the deformations shall alternately reverse in direction on each side, or those on one side shall be reversed in direction from those on the opposite side. Where the line of deformation is over 70 degrees, a reversal in direction is not required.

7.3. The average spacing or distance between deformations on each side of the bar shall not exceed seven tenths of the nominal diameter of the bar.

7.4. The overall length of deformations shall be such that the gap (measured as a cord) between the ends of the deformations shall not exceed 12.5 percent of the nominal perimeter of the bar. Where the ends terminate in a rib, the width of the rib shall be considered as the gap between these ends. The summation of the gaps shall not exceed 25 percent of the nominal perimeter of the bar. The nominal perimeter of the bar shall be 3.1416 times the nominal diameter.

7.5. The spacing, height, and gap of deformations shall conform to the requirements prescribed in Table 1.

8. MEASUREMENTS OF DEFORMATIONS

8.1. The average spacing of deformations shall be determined by measuring the length of a minimum of ten spaces and dividing that length by the number of spaces included in the measurement. The measurement shall begin from a point on a deformation at the beginning of the first space to a corresponding point on a deformation after the last included space. Spacing measurements shall not be made over a bar area containing bar marking symbols involving letters or numbers.

8.2. The average height of deformations shall be determined from measurements made on not less than two typical deformations. Determinations shall be based on three measurements per deformation, one at the center of the overall length and the other two at the quarter points of the overall length.

8.3. Insufficient height, insufficient circumferential coverage, or excessive spacing of deformations shall not constitute cause for rejection unless it has been clearly established by determinations on each lot (Note 2) tested that typical deformation height, gap, or spacing do not conform to the minimum requirements prescribed in Section 7. No rejection may be made on the basis of measurements if fewer than ten adjacent deformations on each side of the bar are measured. Note 2—A lot is defined as all the bars of one bar number and pattern of deformation contained in an individual shipping release or shipping order.

9. TENSILE REQUIREMENTS

9.1. For Type S and Type W materials, as represented by the test specimens, shall conform to the requirements for tensile properties prescribed in Table 3.


Table 3—Tensile Requirements, SI Units Type S

Grade 280 [40] a Type S

Grade 420 [60] Type S

Grade 520 [75] Type S

Grade 550 [80] Tensile strength, min MPa [psi] 420 [60,000] 620550 [9080,000] 690 [100,000] 725690

[105100,000] Yield strength, min, MPa [psi] 280 [40,000] 420 [60,000] 520 [75.000] 550 [80,000] Elongation in 200 mm, min % Bar Designation No. 10 [3] 11 9 7 7 13, 16 [4, 5] 12 9 7 7 19 [6] 12 9 7 7 22, 25 [7, 8] ― 8 7 7 29, 32, 36 [9, 10, 11] ― 7 6 6 43, 57 [14, 18] ― 7 6 6 Type W

Grade 420 [60] Type W

Grade 550 [80] Tensile strength, min MPa [psi] 550 [80,000] b 690 [100,000] b Yield strength, min, MPa [psi] 420 [60,000] 550 [80,000] Yield strength, max , MPa [psi] 540 [78,000] 675 [98,000] Elongation in 200 mm, min % Bar Designation No. 10 [3] 14 12 13, 16 [4, 5] 14 12 19 [6] 14 12 22, 25 [7, 8] 12 12 29, 32, 36 [9, 10, 11] 12 12 43, 57 [14, 18] 10 10

a Grade 280 bars are furnished only in sizes 10 through 19. [Grade 40 bars are furnished only in sizes 3 through 6.] b Tensile strength shall not be less than 1.25 times the actual yield strength.

9.2. The yield point or yield strength shall be determined by one of the following methods:

9.2.1. The yield point shall be determined by drop of the beam or halt of the pointer method as described in Section 14.1.1 of T 244.

9.2.2. Where the steel tested does not have a well-defined yield point, the yield point shall be determined at extension under load using an autographic diagram method or and extensometer as described in Sections 14.1.2 and 14.1.3 of T 244. The extension under load shall be 0.005 mm/mm [0.005 in./in.] of gauge length (0.5 percent) for Grade 280 [40] and Grade 420 [60] and shall be 0.0035 mm/mm [0.0035 in./in.] of gauge length (0.35 percent) for Grade 520 [75]Grade 550 [80].

9.3. When material is furnished in coils, the test sample must be straightened prior to placing it in the jaws of the tensile testing machine. Straightening shall be done carefully to avoid formation of local sharp bends and to minimize cold work. Note 3—Insufficient straightening prior to attaching the extensometer can result in lower-than-actual yield strength readings.

9.4. The percentage of elongation shall be as prescribed in Table 3 when tested in accordance with Section 14.4 of T 244.


10. BENDING REQUIREMENTS

10.1. The bend-test specimen shall withstand being bent around a pin without cracking on the outside radius of the bent portion when tested in accordance with T 285. The requirements for angle of bending and sizes of pins are prescribed in Table 4. When material is furnished in coils, the test sample must be straightened prior to placing it in the bend tester.

10.2. The bend test shall be made on specimens of sufficient length to ensure free bending and with apparatus that provides:

10.2.1. Continuous and uniform application of force throughout the duration of the bending operation.

10.2.2. Unrestricted movement of the specimen at points of contact with the apparatus and bending around a pin free to rotate.

10.2.3. Close wrapping of the specimen around the pin during the bending operation.

10.3. It is permissible to use other methods of bend testing, such as placing a specimen across two pins free to rotate and applying the bending force with a fixed pin. When failures occur under other methods, retests shall be permitted under the bend test method prescribed in Section 10.2.

Table 4—Bend Test Requirements

Bar Designation No. Pin Diameter for Bend Testing of Type S Barsa

Grade 280 [40]a Grade 420 [60] Grade 520 [75] Grade 550 [80] 10, 13, 16 [3, 4, 5] 31/2 d b 31/2 d ― 5 d 19 [6] 5 d 5 d ― 5 d 22, 25 [7, 8] ― 5 d ― 5 d 29, 32 [9, 10] ― 7 d ― 7 d 36 [11] 7 d 7 d 7 d 43, 57 [14, 18], (90˚) ― 9 d 9 d 9 d

Bar Designation No. Pin Diameter for Bend Testing of Type W Barsa

Grade 420 [60] Grade 550 [80] 10, 13, 16 [3, 4, 5] 3 d 31/2 d 19 [6] 4 d 5 d 22, 25 [7, 8] 4 d 5 d 29, 32 [9, 10] 6 d 7 d 36 [11] 6 d 7 d 43, 57 [14, 18], (90˚) 8 d 9 d

a Test bends 180 degrees unless noted otherwise. b d = nominal diameter of specimen.

11. PERMISSIBLE VARIATION IN WEIGHT [MASS]

11.1. The permissible variation shall not exceed 6 percent under nominal mass [weight], except for bars smaller than 9.5 mm [3/8 in.] plain round, the permissible variation in mass [weight] shall be computed on the basis of the permissible variation in diameter in ASTM A510/A510M. For larger bars up to and including 63.5 mm [21/2 in.], use ASTM A6/A6M. Reinforcing bars are evaluated on the basis of nominal mass [weights]. In no case shall the overmass [overweight] of any bar be the cause for rejection.

11.2. The specified limit of variation shall be evaluated in accordance with ASTM E29 (rounding method).


12. FINISH

12.1. The bar shall be free of detrimental surface imperfections.

12.2. Rust, seams, surface irregularities, or mill scale shall not be cause for rejection, provided the weight, dimensions, cross-sectional area, and tensile properties of a hand wire-brushed test specimen are not less than the requirements of this specification.

12.3. Surface imperfections other than those specified in Section 12.2 shall be considered detrimental when specimens containing such imperfections fail to conform to either tensile or bending requirements. Examples include, but are not limited to, laps, seams, scabs, slivers, cooling or casting cracks, and mill or guide marks (Notes 4 and 5). Note 4—Reinforcing bar intended for epoxy coating application should have surfaces with a minimum of sharp edges to achieve proper cover. Particular attention should be given to bar marks and deformations, where coating difficulties are prone to occur. Note 5—Deformed bars destined to be mechanically spliced or butt-welded may require a certain degree of roundness in order for the splices to adequately achieve strength requirements.

13. TEST SPECIMENS

13.1. All mechanical tests shall be conducted in accordance with T 244, including Annex A9.

13.2. Tension test specimens shall be the full section of the bar as rolled. The unit stress determinations on full-sized specimens shall be based on the nominal bar area.

13.3. The bend-test specimens shall be the full section of the bar as rolled.

14. NUMBER OF TESTS

14.1. For bar sizes No. 10 to 36 [3 to 11], inclusive, one tension test and one bend test shall be made of the largest size rolled from each heat. If, however, material from one heat differs by three or more designation numbers, one tension and one bend test shall be made from both the highest and lowest designation numbers of the deformed bars rolled.

14.2. For bar sizes Nos. 43 and 57 [14 and 18] bars, one tension test and one bend test shall be made of each size from each heat.

14.3. For all bar sizes, one set of dimensional property tests, including bar mass [weight] and spacing, height, and gap of deformations, shall be made of each bar size rolled from each heat.

15. RETESTS

15.1. If results of an original tension specimen fail to meet the specified minimum requirements and are within 14 MPa [2000 psi] of the required tensile strength, within 7 MPa [1000 psi] of the required yield strength, or within 2 percentage units of the required elongation, a retest shall be permitted on two random specimens for each original tension specimen failure from the lot. Both retest specimens shall meet the requirements of this specification.

15.2. If a bend test fails for reasons other than mechanical reasons or flaws in the specimen as described in Sections 15.4.2 and 15.4.3, a retest shall be permitted on two random specimens from the same lot. If the results of both test specimens meet the specified requirements, the lot shall be


accepted. The retest shall be performed on test specimens that are at air temperature but not less than 16°C [60°F].

15.3. If a mass [weight] test fails for reasons other than flaws in the specimen as described in Section 15.4.3, a retest shall be permitted on two random specimens from the same lot. Both retest specimens shall meet the requirements of this specification.

15.4. If the original test or any of the random retests fail because of reasons listed in Sections 15.4.1, 15.4.2, or 15.4.3, the test shall be considered an invalid test:

15.4.1. The elongation property of any tension test specimen is less than that specified and any part of the fracture is outside the middle half of the gauge length, indicated by scribe marks on the specimen before testing; Note 6—Marking specimens with multiple scribes or punch marks can reduce the occurrence of fracture outside or near these marks and the need for declaring the test invalid.

15.4.2. Mechanical reasons, such as failure of testing equipment or improper specimen preparation;

15.4.3. Flaws are detected in a test specimen, either before or during the performance of the test.

15.5. The original results from Sections 15.4.1, 15.4.2, or 15.4.3 shall be discarded and the test shall be repeated on a new specimen from the same lot.

16. INSPECTION AND PERIODIC TESTING

16.1. Inspection and periodic testing are important methods for owners and contractors to assure that quality bar products are provided to each project job site.

16.1.1. Initial Purchase—For first-time orders, the purchaser shall have the option to determine if the manufacturer has procedures in place to assure that quality products are provided and are in conformance with the requirements of this specification. Quality indicators include, but are not limited to, controls on processing, sampling and testing, heat identification, marking, bar and scrap segregation, and storage conditions.

16.1.2. Plant Visitation—By agreement with the manufacturer, the purchaser can visit the manufacturer’s plant to observe and sample production of the reinforcing bars that were ordered. The manufacturer shall receive proper notice prior to visitation, which will be conducted at reasonable hours and will not unnecessarily interfere with plant operations.

16.1.3. Periodic Reassessment—Purchasers that maintain lists of qualified manufacturers of steel reinforcing products can establish periodic quality re-assessments in time intervals of one year or more in agreement with the manufacturers. Time intervals for re-assessment shall be based on plant conditions, number of organizational realignments or new ownership, and history of production quality and conformance.

16.1.4. Representatives of Purchasers—The purchaser or ultimate owner of the reinforcing bars covered by this specification shall have the option to authorize qualified representatives to sample, monitor, or test bars for specification conformance. The requirements of Sections 16.1.1, 16.1.2, and 16.1.3 shall also apply to the representatives of purchasers. All significant issues or agreements regarding compliance or conformance with this specification shall be promptly reported to the purchaser and ultimate owner of the reinforcing bars before any final decision is made.


16.2. Product Non-Conformance—If the testing or processing of the reinforcing bars conclusively demonstrate non-conformance with this specification, the purchaser shall have the cooperation of the manufacturer to determine the root cause of the problem. The purchaser shall have the right to observe production and evaluate proposed solutions to correct the deficiencies within a rehearing period not to exceed five working days or other mutually agreeable time table. If the deficiencies of the production lot cannot be remedied, the lot shall be considered as rejectable.

16.3. Purchase Order Cancellation—The manufacturer shall be afforded a reasonable time to correct the root cause of non-conformance. The purchaser and the manufacturer shall mutually agree on a time period for correction of the problem that is reasonable for both parties. If the manufacturer cannot subsequently provide written assurance of conformance, the purchase order shall be considered as voidable.

17. REJECTION

17.1. Unless otherwise specified, any rejection based on tests made in accordance with Section 6.2 shall be reported to the manufacturer within five working days from the receipt of samples by the purchaser.

17.2. Material that shows injurious defects subsequent to its acceptance at the manufacturer’s works will be rejected, and the manufacturer shall be notified.

18. REHEARING

18.1. Samples tested in accordance with Section 6.1 that represent rejected material shall be preserved for two wks from the date rejection is reported to the manufacturer. In case of dissatisfaction with the results of the tests, the manufacturer may make claim for a rehearing within that time.

19. TEST REPORTS

19.1. When specified in the purchase order, report the following information, on a per-heat basis. Additional items may be reported as requested or desired.

19.1.1. Chemical analysis, including carbon, manganese, phosphorus, and sulfur;

19.1.2. Tensile properties;

19.1.3. Bend test; and

19.1.4. Material test report.

19.2. For Type W or Type SW bars, the following information must be reported on a per-heat basis. Report additional items as requested or desired in the purchase order:

19.2.1. Chemical analysis, including elements carbon, manganese, phosphorus, sulfur, silicon, copper, nickel, chromium, molybdenum, and vanadium;

19.2.2. Carbon equivalent in accordance with Section 6.1.3;

19.2.3. Tensile properties;

19.2.4. Bend test results; and


19.2.5. Material test report.

19.3. 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 AASHTO 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.

20. MARKING

20.1. When loaded for mill shipment, bars shall be properly separated and tagged with the manufacturer’s heat or test identification number.

20.2. Each producer shall identify the symbols of his or her marking system.

20.3. All bars produced to this specification, except plain round bars that shall be tagged for grade, shall be identified by a distinguishing set of marks legibly rolled into the surface of one side of the bar to denote, in the following order:

20.3.1. Point of Origin—Letter or symbol established as the producer’s mill designation.

20.3.2. Size Designation—Arabic number corresponding to bar designation number of Table 1.

20.3.3. Type of Steel—The letters S or W indicate that the bar was produced to this specification for Grade 420 [60], Grade 520 [75], or Grade 550 [80] bars only; the letter S indicates that the bar was produced to meet M 31M/M 31 Type S and ASTM A615; the letter W indicates that the bar was produced to meet M 31M/M 31 Type W and ASTM A706/A706M. A Type W bar will also meet the requirements for Type S bars of the same Grade. The letters S and W together indicate that the bar was produced to meet both S and W requirements. Grade 40 Type S bars have no markings.

20.3.4. Minimum Yield Designation—For Grade 420 [60] bars, either the number 4 [60] or a single continuous longitudinal line through at least five spaces offset from the center of the bar side. For Grade 520 [75] bars, either the number 5 [75] or two continuous longitudinal lines through at least five spaces offset each direction from the center of the bar. For Grade 550 [80] bars, either the number 80 [6] or three continuous longitudinal lines through at least five spaces offset each direction from the center of the bar. No yield strength marking designation for Grade 280 [40] bars is required.

20.3.5. It shall be permissible to substitute: a metric size bar of Grade 280 for the corresponding inch-pound size bar of Grade 40, a metric size bar of Grade 420 for the corresponding inch-pound size bar of Grade 60, a metric size bar of Grade 520 for the corresponding inch-pound size bar of Grade 75, and a metric size bar of Grade 550 for the corresponding inch-pound size bar of Grade 80.

21. PACKAGING AND PACKAGE MARKING

21.1. When specified in the purchase order, packaging shall be in accordance with the procedures in ASTM A700.

21.2. When specified in the contract or order, and for direct procurement by or direct shipment to the U.S. Government, material shall be preserved, packaged, and marked in accordance with the requirements of MIL-STD-163. The applicable levels shall be as specified in the contract.


Marking for shipment shall be in accordance with Fed. Std. No. 123 for civil agencies and MIL-STD-129 for military agencies.

22. KEYWORDS

22.1. Carbon equivalent; concrete reinforcement; deformations (protrusions); steel bars.

1 Agrees with ASTM A615/A615M-16 20 except for the bend testing procedure, which is referenced to T 285 and Section 9.2.2; and the addition of Type W bars.

COMP TS Mid‐Year Calls—Planning for Next Year: Full Standards

Designation No. Title ASTM Equiv.

Review for Next Year

TS 4f

LatestASTM Internal? Harmonization?

Deformed and Plain Carbon and Low‐Alloy Steel Bars for Concrete Reinforcement

A615/A615M‐20M 031M/M 031‐21 NoA615/A615M‐20 No

Welded Deformed Steel Bar Mats for Concrete Reinforcement A184/A184M‐17M 054M/M 054‐19 NoA184/A184M‐19 Yes

Steel Forgings, Carbon and Alloy, for General Industrial Use A668/A668M‐17M 102M/M 102‐19 NoA668/A668M‐20a

Yes

Steel Castings, Carbon, for General Application A27/A27M‐17M 103M/M 103‐19 NoA27/A27M‐20 Yes

Gray Iron CastingsM 105‐09 (2018) Yes N/A

Zinc (Hot‐Dip Galvanized) Coatings on Iron and Steel Products A123/A123M‐17M 111M/M 111‐19 NoA123/A123M‐17 No

Castings, Iron‐Chromium, Iron‐Chromium‐Nickel, Corrosion Resistant, for General Application

A743/A743M‐19M 163M/M 163‐20 NoA743/A743M‐19 No

Steel Bars, Carbon and Alloy, Cold‐Finished A108‐18M 169‐20 NoA108‐18 No

Steel Sheet Piling A328/A328M‐13aM 202M/M 202‐19 NoA328/A328M‐13a

No

Steel Strand, Uncoated Seven‐Wire for Concrete Reinforcement A416/A416M‐18M 203M/M 203‐20 NoA416/A416M‐18 No

Stress‐Relieved Steel Wire for Prestressed Concrete A421/A421M‐15M 204M/M 204‐19 NoA421/A421M‐15 No

Steel Bars, Carbon, Merchant Quality, Mechanical Properties A663/A663M‐17M 227M/M 227‐19 NoA663/A663M‐17 No

Zinc Coating (Hot‐Dip) on Iron and Steel Hardware A153/A153M‐16aM 232M/M 232‐19 NoA153/A153M‐16a

No

Corrosion‐Resistant Coated Dowel BarsM 254‐06 (2019) No N/A

Steel Bars, Carbon, Hot‐Wrought, Special Quality, Mechanical Properties

A675/A675M‐14(2019)

M 255M/M 255‐19 NoA675/A675M‐14(2019)

No

Structural Steel for Bridges A709/A709M‐18M 270M/M 270‐20 NoA709/A709M‐18 No

Uncoated High‐Strength Steel Bars for Prestressing Concrete A722/A722M‐18M 275M/M 275‐20 NoA722/A722M‐18 No

Wire Rope and Sockets for Movable BridgesM 277‐06 (2019) No N/A

Friday, November 13, 2020 Prepared for COMP by AASHTO Publications




TS 4f


Castings, Iron‐Chromium‐Nickel, Corrosion Resistant, for Severe Service

A744/A744M‐13M 285M/M 285‐19 NoA744/A744M‐20 Yes

Carbon and Alloy Steel Nuts for Bolts for High‐Pressure or High‐Temperature Service, or Both

A194/A194M‐17aM 292M/M 292‐20 NoA194/A194M‐20a

Yes

Drainage, Sewer, Utility, and Related CastingsM 306‐10 (2019) No N/A

Steel Anchor BoltsM 314‐90 (2018) Yes N/A

Rail‐Steel and Axle‐Steel Deformed Bars for Concrete Reinforcement A996/A996M‐09M 322M/M 322‐10 (2019)

NoA996/A996M‐16 Yes

Stainless Clad Deformed and Plain Round Steel Bars for Concrete Reinforcement

M 329M/M 329‐11 (2019)

No N/A

Uncoated, Corrosion‐Resistant, Deformed and Plain Chromium Alloyed, Billet‐Steel Bars for Concrete Reinforcement and Dowels

M 334M/M 334‐17 (2021)

No N/A

Steel Wire and Welded Wire, Plain and Deformed, for Concrete Reinforcement

M 336M/M 336‐20 No N/A

Mass [Weight] of Coating on Iron and Steel Articles with Zinc or Zinc‐Alloy Coatings

A90/A90M‐13(2018)T 065M/T 065‐19 NoA90/A90M‐13(2018)

No

Mass [Weight] of Coating on Aluminum‐Coated Iron or Steel Articles A428/A428M‐10(2019)

T 213M/T 213‐11 (2019)

NoA428/A428M‐10(2019)

No

Sampling Procedure for Impact Testing of Structural Steel A673/A673M‐17T 243M/T 243‐19 NoA673/A673M‐17 No

Mechanical Testing of Steel Products A370‐18T 244‐20 NoA370‐20 Yes

Coated Dowel BarsT 253‐02 (2020) No N/A

Bend Test for Bars for Concrete ReinforcementT 285‐89 (2019) No N/A

Sensitivity of Stainless Steel to Intergranular AttackT 372M/T 372‐17 (2021)

No N/A





TS 4f


Comparative Qualitative Corrosion Characterization of Steel Bars Used for Concrete Reinforcement (Linear Polarization Resistance and Potentiodynamic Polarization Tests)

T 373M/T 373‐17 (2021)

No N/A

Comparative Qualitative Corrosion Characterization of Uncoated Chromium‐Alloyed Steel Bars Used for Concrete Reinforcement (Tombstone Test)

T 374M/T 374‐17 (2021)

No N/A

Identification of Iron‐Based Alloy Steel Bars for Concrete Reinforcement or Dowels by Handheld X‐Ray Fluorescence (XRF) Spectrometer

T 375M/T 375‐17 (2021)

No N/A

Macrocell Slab Chloride ThresholdT 376M/T 376‐17 (2021)

No N/A


COMP TS Mid‐Year Calls—Planning for Next Year: Provisional Standards TS 4fDesignation No. Title Planning for Next Year NeededPub Yr. 1

TP 138‐20Weight and Diameter for Carbon‐Steel for Steel Wire and Welded Wire Reinforcement for Concrete

TP 138‐20 Start Revise or 2‐Yr. Reconfirm Review2020


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