1、Designation: A996/A996M 15Standard Specification forRail-Steel and Axle-Steel Deformed Bars for ConcreteReinforcement1This standard is issued under the fixed designation A996/A996M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers rail-steel and axle-steel barsfor concrete reinforcement. Three types of product
3、 areincluded, designated with a “rail symbol,” and an “R” for barsmade of rail-steel and with an “A” for bars made of axle-steel.The standard sizes and dimensions of deformed bars and theirnumber designations are given in Table 1. All sizes and gradesof all types may not be readily available; manufa
4、cturers shouldbe consulted to verify availability.1.2 The text of this specification references notes andfootnotes that provide explanatory material. These notes andfootnotes, excluding those in tables and figures, shall not beconsidered as requirements of the specification.1.3 Type “rail symbol” an
5、d Type R are of two minimumyield strength levels, namely 50 000 psi 350 MPa and 60 000psi 420 MPa designated as Grade 50 350 and Grade 60420, respectively. Type A is of two minimum yield levels,namely 40 000 psi 280 MPa and 60 000 psi 420 MPadesignated as Grade 40 280 and Grade 60 420, respectively.
6、1.4 The weldability of the steel is not a requirement of thisspecification.1.5 This specification is applicable for orders in eitherinch-pound units (Specification A996) or SI units (Specifica-tion A996M).1.6 The values stated in either inch-pound units or SI unitsare to be regarded as standard. Wit
7、hin the text, the SI units areshown in brackets. The values stated must be used indepen-dently of the other. Combining values from the two systemsmay result in nonconformance with the specification.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its u
8、se. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA
9、700 Guide for Packaging, Marking, and Loading Methodsfor Steel Products for ShipmentA751 Test Methods, Practices, and Terminology for Chemi-cal Analysis of Steel ProductsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE290 Test Methods for Bend Testi
10、ng of Material for Ductil-ity2.2 Military Standard:3MIL-STD-129 Marking for Shipment and Storage2.3 Federal Standard:3Fed. Std. No. 123 Marking for Shipment (Civil Agencies)3. Terminology3.1 Definitions of Terms Specific to This Specification:3.1.1 deformations, ntransverse protrusions on a de-forme
11、d bar.3.1.2 deformed bar, nsteel bar with transverse protrusions;a bar that is intended for use as reinforcement in reinforcedconcrete construction.3.1.2.1 DiscussionThe surface of the bar is provided withprotrusions that inhibit longitudinal movement of the barrelative to the concrete surrounding t
12、he bar in such construc-tion. The protrusions conform to the provisions of this speci-fication.3.1.3 rib, nlongitudinal protrusion on a deformed bar.4. Ordering Information4.1 Orders for rail-steel or axle-steel reinforcing bars underthis specification shall contain the following information:1This s
13、pecification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.05 on Steel Reinforcement.Current edition approved July 1, 2015. Published August 2015. Originallyapproved in 1998. Last previous edition appro
14、ved in 2014 as A996/A996M 14a.DOI: 10.1520/A0996_A0996M-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3A
15、vailable from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/www.dodssp.daps.mil.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
16、, PA 19428-2959. United States14.1.1 Quantity (weight) mass,4.1.2 Type “rail symbol” or Type R for rail steel, or Type Afor axle steel,4.1.3 Bar designation number (size),4.1.4 Grade (see Table 2),4.1.5 Packaging (see Section 20), and4.1.6 ASTM designation and year of issue.4.2 The purchaser shall h
17、ave the option to specify additionalrequirements, including but not limited to, the following:4.2.1 Carbon range for each lot of bars (6.2), and4.2.2 Other special requirements, if any.5. Materials and Manufacture5.1 The bars shall be rolled from standard section Tee railsor from carbon steel axles
18、for railway cars and locomotives. Noother materials, such as those known by the terms “rerolled,rail-steel equivalent, and rail-steel quality” shall be substituted.6. Carbon Determination6.1 The chemical analysis of the material, as describedbelow, shall be determined in accordance with Test Methods
19、,Practices, and Terminology A751. For axle-steel product, themanufacturer shall make a determination for the carbon contentof each axle received for manufacture into reinforcing bars.Based on these carbon determinations, all steel axles shall bestocked for subsequent rolling in separated lots by car
20、bonrange. The ranges of carbon shall be determined by themanufacturer as those best suited to meet the mechanicalrequirements.6.2 When requested by the purchaser, the manufacturershall report the carbon range for each lot of bars furnished.7. Requirements for Deformations7.1 Deformations shall be sp
21、aced along the bar at substan-tially uniform distances. The deformations on opposite sides ofthe bar shall be similar in size, shape, and pattern.7.2 The deformations shall be placed with respect to the axisof the bar so that the included angle is not less than 45. Wherethe line of deformations form
22、s an included angle with the axisof the bar from 45 to 70 inclusive, the deformations shallreverse alternately in direction from those on the opposite side.Where the line of deformations is over 70, reversal indirection shall not be required.7.3 The average spacing or distance between deformationson
23、 each side of the bar shall not exceed seven tenths of thenominal diameter of the bar.7.4 The overall length of the deformations shall be such thatthe gap (measured as a chord) between the ends of thedeformations shall not exceed 12.5 % of the nominal perimeterof the bar. Where the ends terminate in
24、 a rib, the width of therib shall be considered as the gap between these ends. Thesummation of the gaps shall not exceed 25 % of the nominalperimeter of the bar. Furthermore, the summation of gaps shallnot exceed 25 % of the nominal permeter of the bar. Thenominal perimeter of the bar shall be 3.141
25、6 times the nominaldiameter.7.5 The spacing, height, and gap of deformations shallconform to the requirements prescribed in Table 1.8. Measurements of Deformation8.1 The average spacing of deformations shall be deter-mined by measuring the length of a minimum of 10 spaces anddividing that length by
26、the number of spaces included in themeasurement. The measurement shall begin from a point on adeformation at the beginning of the first space to a correspond-ing point on a deformation after the last included space.TABLE 1 Deformed Bar Designation Numbers, Nominal Weights Masses, Nominal Dimensions,
27、 and Deformation RequirementsBarDesignationNo.BNominalWeight,lb/ftNominalMass,kg/mNominal DimensionsADeformation Requirements, in. mmDiameter,in. mmCross-SectionalAreain.2mm2Perimeter,in. mmMaximumAverageSpacingMinimumAverageHeightMaximumGap (Chordof 12.5 % ofNominalPerimeter)3 10 0.376 0.560 0.375
28、9.5 0.11 71 1.178 29.9 0.262 6.7 0.015 0.38 0.143 3.64 13 0.668 0.994 0.500 12.7 0.20 129 1.571 39.9 0.350 8.9 0.020 0.51 0.191 4.95 16 1.043 1.552 0.625 15.9 0.31 199 1.963 49.9 0.437 11.1 0.028 0.71 0.239 6.16 19 1.502 2.235 0.750 19.1 0.44 284 2.356 59.8 0.525 13.3 0.038 0.97 0.286 7.37 22 2.044
29、3.042 0.875 22.2 0.60 387 2.749 69.8 0.612 15.5 0.044 1.12 0.334 8.58 25 2.670 3.973 1.000 25.4 0.79 510 3.142 79.8 0.700 17.8 0.050 1.27 0.383 9.79 29 3.400 5.060 1.128 28.7 1.00 645 3.544 90.0 0.790 20.1 0.056 1.42 0.431 10.910 32 4.303 6.404 1.270 32.3 1.27 819 3.990 101.3 0.889 22.6 0.064 1.63 0
30、.487 12.411 36 5.313 7.907 1.410 35.8 1.56 1006 4.430 112.5 0.987 25.1 0.071 1.80 0.540 13.7AThe nominal dimensions of a deformed bar are equivalent to those of a plain round bar having the same weight mass per foot metre as the deformed bar.B9 29 11 36 axle-steel bars only.TABLE 2 Tensile Requireme
31、ntsGrade 40 280 Grade 50 350 Grade 60 420Tensile strength,min, psi MPa70 000 500 80 000 550 90 000 620Yield strength,min, psi MPa40 000 280 50 000 350 60 000 420Type ARailSymboland RARailSymboland RElongation in 8 in. 200mm,min,%Bar Designation no.3 10 11 6 8 64, 5, 6 13, 16, 19 12 7 8 67 22 11 6 8
32、58 25 10 5 7 4.59, 10, 11 29, 32, 36 . . 7 .A996/A996M 152Spacing measurements shall not be made over a bar areacontaining bar marking symbols involving letters or numbers.8.2 The average height of deformations shall be determinedfrom measurements made on not less than two typical defor-mations. Det
33、erminations shall be based on three measurementsper deformation, one at the center on the overall length and theother two at the quarter points of the overall length.8.3 Insufficient height, insufficient circumferentialcoverage, or excessive spacing of deformations shall notconstitute cause for reje
34、ction unless it has been clearly estab-lished by determinations on each lot (Note 1) tested that typicaldeformation height, gap, or spacing does not conform to theminimum requirements prescribed in Section 7. No rejectionshall be made on the basis of measurements if fewer than tenadjacent deformatio
35、ns on each side of the bar are measured.NOTE 1As used within the intent of 8.3 and 14.1, the term “lot” shallmean all the bars of one bar number and pattern of deformations containedin an individual shipping release or shipping order.9. Tensile Requirements9.1 The material, as represented by the tes
36、t specimens, shallconform to the requirements for tensile properties prescribed inTable 2.9.2 The yield point or yield strength shall be determined byone of the following methods.9.2.1 The yield point shall be determined by the drop of thebeam or halt in the gage of the tensile testing machine.9.2.2
37、 Where the steel tested does not have a well-definedyield point, the yield strength shall be determined by the offsetmethod (0.2 % offset), as described in Test Methods andDefinitions A370.9.3 The percentage of elongation shall be as prescribed inTable 2.10. Bending Requirements10.1 The bend test sp
38、ecimen shall withstand being bentaround a pin without cracking on the outside radius of the bentportion. The requirements for degree of bending and sizes ofpins are prescribed in Table 3.10.2 The bend test shall be made on specimens of sufficientlength to ensure free bending and with an apparatus th
39、atprovides the following.10.2.1 Continuous and uniform application of forcethroughout the duration of the bending operation.10.2.2 Unrestricted movement of the specimen at points ofcontact with the apparatus and bending around a pin free torotate.10.2.3 Close wrapping of the specimen around a pin du
40、ringthe bending operation.10.3 It shall be permissible to use other methods of bendtesting described in Test Methods E290, such as placing aspecimen across two round bearings free to rotate and applyingthe bending force with a fixed rounded-tip mandrel conformingto the specified bend radius, allowin
41、g the bar to pass throughwith sufficient clearance. When failures occur under othermethods of bend testing, retest shall be permitted under thebend test method prescribed in 10.2.11. Permissible Variation in Weight Mass11.1 Deformed reinforcing bars shall be evaluated on thebasis of nominal weight m
42、ass. The weight mass determinedusing the measured weight mass of the test specimen androunding in accordance with Practice E29, shall be at least94 % of the applicable weight mass per unit length prescribedin Table 1. In no case shall overweight excess mass of anydeformed bar be cause for rejection.
43、12. Finish12.1 The bars shall be free of detrimental surface imperfec-tions.12.2 Rust, seams, surface irregularities, or mill scale shallnot be cause for rejection, provided the weight, dimensions,cross-sectional area, and tensile properties of a hand wirebrushed test are not less than requirements
44、of this specification.12.3 Surface imperfections or flaws other than those speci-fied in 12.2 shall be considered detrimental when specimenscontaining such imperfections fail to conform to either tensileor bending requirements. Examples include, but are not limitedto, laps, seams, slivers, cooling o
45、r casting cracks, and mill orguide marks.13. Test Specimens13.1 All mechanical tests shall be conducted in accordancewith Test Methods and Definitions A370. In case of anyconflict between the requirements in this specification and therequirements of Test Methods and Definitions A370, therequirements
46、 in this specification shall prevail13.2 Tension test specimens shall be the full section of baras rolled. Unit stress determinations for yield and tensilestrength shall be based on the nominal bar area.13.2.1 Tension test specimens shall be long enough toprovide for an 8-in. 200-mm gage length, a d
47、istance of atleast two bar diameters between each gage mark and the grips.NOTE 2It is recommended that sufficient additional length of the testspecimen be provided to fill the grips completely, leaving some excesslength protruding beyond each grip. The grips should be shimmed so thatno more than12 i
48、n. 13 mm of a grip protrudes from the head of thetensile testing machine.13.2.2 Gage MarksThe 8-in. 200-mm gage length shallbe marked on the specimen using a preset 8-in. 200-mmpunch or, alternately, may be punch marked every 2 in. 50mm along the 8-in. 200-mm gage length, on one of thelongitudinal r
49、ibs, if present, or in the clear spaces betweenTABLE 3 Bend Test RequirementsPin Diameter for Bend TestABar Designation Nos.Type RailSymbolType R Type A3, 4, 5 10, 13, 16 6dB312 d 312 d6, 7, 8 19, 22, 25 6d 5d 5d9, 10, 11 29, 32, 36 . . 7dATest bends 180.Bd = nominal diameter of specimen.A996/A996M 153transverse deformati
