ASTM A911/A911M-99

Standard Specification for Uncoated, Stress-Relieved Steel Bars for Prestressed Concrete Ties

SCOPE
1.1 This specification covers uncoated stress-relieved steel bars for use in prestressed concrete railroad ties.
1.2 Annex A1 describes low-relaxation bars and relaxation testing for that product. Low-relaxation bars shall be furnished when specifically ordered, and may be furnished in place of regular bars if mutually agreed to by the purchaser and supplier.
1.3 This specification is applicable for orders in either inch-pounds units (as specification A911) or in SI units (as Specification A911M).
1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standards. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

General Information

• Status: Historical
• Publication Date: 09-Sep-1999
• 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

• Replaced By: ASTM A911/A911M-02 - Standard Specification for Uncoated, Stress-Relieved Steel Bars for Prestressed Concrete Ties
• Effective Date: 10-Sep-2002

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: A 911/A 911M – 99
Standard Specification for
Uncoated, Stress-Relieved Steel Bars for Prestressed
Concrete Railroad Ties
This standard is issued under the fixed designation A 911/A 911M; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 This specification covers uncoated stress-relieved steel 3.1 Definitions of Terms Specific to This Standard:
bars for use in prestressed concrete railroad ties. 3.1.1 lot, n—all the coils of bars of the same nominal bar
1.2 Supplement I describes low-relaxation bars and relax- size contained on an individual shipping release or shipping
ation testing for that product. Low-relaxation bars shall be order, from the same cast or heat of steel.
furnished when specifically ordered, and may be furnished in
4. Ordering Information
place of regular bars if mutually agreed to by the purchaser and
4.1 It shall be the responsibility of the purchaser to specify
manufacturer.
1.3 This specification is applicable for orders in either all requirements that are necessary for bars ordered to this
specification. Such requirements shall include, but are not
inch-pounds units (as Specification A 911) or in SI units (as
Specification A 911M). limited to, the following:
4.1.1 Quantity (weight) [mass],
1.4 The values stated in either inch-pound units or SI units
are to be regarded separately as standards. Within the text, the 4.1.2 Name of material (uncoated, stress-relieved bars for
prestressed concrete railroad ties),
SI units are shown in brackets. The values stated in each
system are not exact equivalents; therefore, each system must 4.1.3 Diameter of bar (inches) [millimetres],
4.1.4 Packaging,
be used independently of the other. Combining values from the
two systems may result in nonconformance with the specifi- 4.1.5 ASTM designation and year of issue, and
4.1.6 Special requirements, if any.
cation.
NOTE 1—A typical ordering description is as follows: 100 tons [90 t]
2. Referenced Documents
uncoated, stress-relieved steel bars for prestressed concrete railroad ties,
2.1 ASTM Standards:
0.394-in. [10-mm] diameter bars in 6.5-ft [2.0-m] diameter coils to ASTM
A 370 Test Methods and Definitions for Mechanical Testing
A XXX – [A XXXM – ].
of Steel Products
5. Manufacture
E 328 Methods for Stress-Relaxation Tests for Materials
5.1 The bars shall be made from properly identified heats of
and Structures
steel made by the electric-furnace, the open-hearth, or the basic
2.2 Federal Standard:
Fed. Std. No. 123 Marking for Shipments (Civil Agencies) oxygen process.
5.2 After hot-rolling, the bars shall be cold-drawn and
2.3 Military Standards:
MIL-STD-129 Marking for Shipment and Storage finally stress-relieved by induction heat treatment to produce
the desired mechanical properties and then coiled.
MIL-STD-163 Steel Mill Products Preparation for Ship-
ment and Storage
6. Chemical Requirements
6.1 An analysis of each heat of steel shall be made by the
This specification is under the jurisdiction of ASTM Committee A-1 on Steel,
manufacturer from test samples taken during the pouring of
Stainless Steel, and Related Alloys and is the direct responsibility of Subcommittee
each heat.
A01.05 on Steel Reinforcement.
6.2 The analysis of the steel shall conform to the chemical
Current edition approved Sept. 10, 1999. Published November 1999. Originally
published as A 911/A 911M – 92. Last previous edition A 911/A 911M – 92.
requirements specified in Table 1.
Annual Book of ASTM Standards, Vol 01.03.
Annual Book of ASTM Standards, Vol 03.01.
Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700
Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
A 911/A 911M – 99
TABLE 1 Chemical Requirements TABLE 3 Relaxation Requirements
A
Element Composition, % f /f Max Stress Losses after 1000 h, %
pi pu
A
Carbon 0.70–0.90 0.50 1.0
Silicon 0.10–0.35 0.60 1.0
B
Manganese 0.50–0.90 0.70 2.5
Chromium, max 0.15 0.80 5.0
Phosphorus, max 0.030
A
f = initial prestress load, and
pi
Sulphur, max 0.035
f = specified minimum tensile strength.
pu
Copper, max 0.30
A
Carbon in any one lot shall not vary more than 0.13 %.
B
Manganese in any one lot shall not vary more than 0.30 %. 9.1.1 There shall be no welds or joints in the finished bar.
Any welds or joints made during manufacture to promote
continuity of operations shall be removed.
7. Mechanical Requirements
9.2 The finished bar shall be uniform in diameter in con-
7.1 Test Method—Tests shall be made in accordance with formance with Section 8 and shall be free of imperfections not
consistent with good commercial practice.
Test Methods and Definitions A 370, including Annex A4,
using full-size bar specimens taken from either end of the coil 9.3 Straightness—After uncoiling, there shall be no residual
out of line deformation greater than 0.4 in. [10 mm] in a length
of the finished product.
7.2 Tensile Strength—The minimum tensile strength of the of 40 in. [1000 mm].
finished bar, as represented by test specimens, shall conform to
10. Sampling
the requirements prescribed in Table 2.
10.1 Test specimens may be taken from either end of the
7.3 Yield Strength—Yield strength shall be measured at 1 %
coil. Any specimen found to contain a joint should be discarded
extension under load. The load at this extension is recorded as
yield strength and shall meet the requirements of Table 2. and a new specimen obtained.
7.4 Elongation—The total elongation after rupture shall not
11. Number of Tests
be less than 6.0 % and shall be measured in a gage length of 4
11.1 One test specimen each for the tensile test and the
in. [100 mm].
wrapping test shall be taken for each 10 coils or fraction
7.5 Wrapping Test—Bars shall withstand being wound
thereof in a lot.
around a mandrel with a diameter of five times the bar diameter
without cracking or other surface defects occurring on the
12. Inspection
outside of the bent portion. The bar shall be bent around the
12.1 The purchaser shall be allowed to request that a
mandrel 1 ⁄2 turns beginning with a 90° bend.
representative inspect or witness the inspection and testing of
8. Dimensions and Permissible Variations the material prior to shipment. Such agreement shall be made
by the purchaser and manufacturer as part of the purchase
8.1 The size of the finished bar shall be expressed as the
contract.
nominal diameter of the bar in decimals of an inch [millime-
12.2 When such inspection or witness of inspection and
ter]. The required initial diameters before cold-drawing, and
testing is agreed upon, the purchaser’s representative shall be
the final diameters after cold-drawing shall be as follows:
afforded reasonable access to facilities to assure that the
Initial Diameter Final Diameter
material meets the requ
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