1、Designation: A970/A970M 13A970/A970M 13aStandard Specification forHeaded Steel Bars for Concrete Reinforcement1This standard is issued under the fixed designation A970/A970M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year
2、 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 deformed steel reinforcing bars in cut lengths, with a head attached to one or both end
3、s, forconcrete reinforcement. Heads are forge-formed, machined from bar stock, or cut from plate. Attachment can be accomplishedthrough:1.1.1 Welding;1.1.2 Integrally hot forging of a head from the reinforcing bar end;1.1.3 Internal threads in the head mating to threads on the bar end;1.1.4 Cold-swa
4、ging an externally threaded coupling sleeve onto the reinforcing bar;1.1.5 Cold-extruding an external coupling sleeve onto the reinforcing bar;1.1.6 Cold-swaging an external coupling sleeve or headed sleeve onto the reinforcing bar;1.1.7 Attaching a coupling sleeve to the end of the reinforcing bar
5、by means of the means of a ferrous-filler medium; or1.1.8 Separate threaded nut to secure the head to the bar.NOTE 1The requirements of this specification are only applicable to headed bars where the attachment of the head is accomplished by one of themethods listed in 1.1.1.2 Limitations on head di
6、mensions and on obstructions and interruptions of bar deformations on the non-planar features on thebearing face of the head are presented in Annex A1. The requirements in Annex A1 only apply when specified by the purchaser(see 4.1.13).1.3 This specification is applicable for orders in either inch-p
7、ound units as Specification A970 or SI units as SpecificationA970M.1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI unitsare shown in brackets. The values stated in each system may not be exact equivalents; therefore, eac
8、h system shall be usedindependently of the other. Combining values from the two systems may result in non-conformance with the specification.1.5 This specification does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this sta
9、ndard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA615/A615M Specification for Deformed and Plain Carbon
10、-Steel Bars for Concrete ReinforcementA700 Practices for Packaging, Marking, and Loading Methods for Steel Products for ShipmentA706/A706M Specification for Low-Alloy Steel Deformed and Plain Bars for Concrete Reinforcement2.2 AWS Standards:3AWS C6.1 Recommended Practices for Friction WeldingAWS D1.
11、4/D1.4M Structural Welding Code - Reinforcing Steel1 This specification is under the jurisdiction of ASTM A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of A01.05 on Steel Reinforcement.Current edition approved April 1, 2013July 1, 2013. Published May 2013July 2013
12、. Originally approved in 1997. Last previous edition approved in 20122013 asA970/A970M 12.A970/A970M 13. DOI: 10.1520/A0970_A0970M-13.10.1520/A0970_A0970M-13A.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM customer service at serviceastm.org. For Annual Book o
13、f ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http:/www.aws.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM stand
14、ard an indication of what changes have been made to the previous version. Becauseit 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 versionof the standard as published by ASTM
15、 is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.3 U.S. Military Standard:4MIL-STD-129 Marking for Shipment and Storage2.4 U.
16、S. Federal Standard:4Fed. Std. No. 123 Marking for Shipment (Civil Agencies)2.5 ACI Standard:5ACI 318 Building Code Requirements for Structural Concrete3. Terminology3.1 Definitions:3.1.1 cold-extruded coupling sleeve headed bar(similar to cold-swaged threaded coupling sleeve headed bar); steelreinf
17、orcing bar used in the reinforcement of concrete that has the head(s) attached to one or both ends by means of a couplingsleeve that is axially cold- extruded onto the bar end(s).This extruded coupling sleeve consists of an axially extruded sleeve portionthat engages the deformed reinforcing bar and
18、 a pre-threaded integral stud with external threads, which match threads internal tothe head(s). The head is screwed onto the mating threads on the extruded coupling sleeve. The threads may be parallel or tapered.3.1.1.1 DiscussionSimilar to cold-swaged threaded coupling sleeve headed bar. This extr
19、uded coupling sleeve consists of an axially extruded sleeveportion that engages the deformed reinforcing bar and a pre-threaded integral stud with external threads, which match threadsinternal to the head(s). The head is screwed onto the mating threads on the extruded coupling sleeve. The threads ma
20、y be parallelor tapered.3.1.2 cold-swaged external sleeve headed bar(similar to cold-swaged threaded coupling sleeve headed bar); steel reinforcingbar used in the reinforcement of concrete that has the head(s) attached to one or both ends by means of a coupling sleeve that iscold- swaged cold-swaged
21、 onto the bar end(s). This sleeve is a combination of a tubular sleeve portion extending in front of thehead, and an integral one-piece head immediately adjacent to the cold-swaged sleeve. The sleeve and head assembly is attachedto the deformed reinforcing bar by cold-swaging the tubular sleeve port
22、ion to the bar with multiple crimps from a hydraulicswaging tool and die, up to the face of the head section.3.1.2.1 DiscussionSimilar to cold-swaged threaded coupling sleeve headed bar. This sleeve is a combination of a tubular sleeve portion extendingin front of the head, and an integral one-piece
23、 head immediately adjacent to the cold-swaged sleeve. The sleeve and head assemblyis attached to the deformed reinforcing bar by cold-swaging the tubular sleeve portion to the bar with multiple crimps from ahydraulic swaging tool and die, up to the face of the head section.3.1.3 cold-swaged headed s
24、leeve headed bar(similar to cold-swaged external coupling sleeve headed bar); steel bar used inthe reinforcement of concrete steel reinforcing bar that has the head(s) attached to one or both ends by means of a sleeve that iscold-swaged onto the bar end(s). This sleeve is a one-piece unit with an in
25、tegral cold-swaged head. The head assembly is attachedto the deformed reinforcing bar by cold-swaging the tubular sleeve to the bar with a hydraulic swaging tool and die.3.1.3.1 DiscussionSimilar to cold-swaged external coupling sleeve headed bar. This sleeve is a one-piece unit with an integral col
26、d-swaged head. Thehead assembly is attached to the deformed reinforcing bar by cold-swaging the tubular sleeve to the bar with a hydraulic swagingtool and die.3.1.4 cold-swaged threaded coupling sleeve headed barsteel reinforcing bar used in the reinforcement of concrete that has thehead(s) attached
27、 to one or both ends by means of a coupling sleeve that is cold-swaged onto the bar end(s). The coupling sleeveassembly is attached to the deformed reinforcing bar by cold-swaging the tubular sleeve portion to the bar with multiple crimpsfrom a hydraulic swaging tool and die, up to the face of the p
28、rethreaded section. This coupling sleeve is pre-threaded with externalthreads, which match threads internal to the head(s). The head is screwed onto the mating threads on the coupling sleeve. Thethreads may be parallel or tapered.3.1.4.1 Discussion4 Available from Standardization Documents Order Des
29、k, Bldg. 4 Section D, 700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS. Or visit: http:/assist.daps.dla.mil/online.5 Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:/www.concrete.org.A970/A970M 13a2The coupling sleeve assembly is attac
30、hed to the deformed reinforcing bar by cold-swaging the tubular sleeve portion to the barwith multiple crimps from a hydraulic swaging tool and die, up to the face of the prethreaded section. This coupling sleeve ispre-threaded with external threads, which match threads internal to the head(s). The
31、head is screwed onto the mating threads onthe coupling sleeve. The threads may be parallel or tapered.3.1.5 ferrous-filler coupling sleeve headed barsteel reinforcing bar used in the reinforcement of concrete that has the head(s)attached to one or both ends by means of a coupling sleeve mechanically
32、 attached to the bar by means of via an interlock offerrous-filler material and the bar deformations. The ferrous-filler material is cast into the coupling sleeve. A variation includes aseparate internally threaded nut secured to the threaded bar end or attached by means of welding a plate to the en
33、d of a preparedcoupling sleeve3.1.5.1 DiscussionThe ferrous-filler material is cast into the coupling sleeve. A variation includes a separate internally threaded nut secured to thethreaded bar end or attached via welding a plate to the end of a prepared coupling sleeve.3.1.6 forged headed barsteel r
34、einforcing bar that has the head(s) integrally forged.3.1.7 headround, elliptical, or rectangular shape used to anchor a steel reinforcing bar in concrete.3.1.8 net bearing areagross cross-sectional area of the head minus the nominal cross-sectional area of the deformedreinforcing bar.3.1.9 threaded
35、 headed barsteel reinforcing bar that has the head(s) attached using tapered or straight threads internal to thehead or by a separate internally threaded nut securing the head to the threaded bar end.3.1.10 welded headed barsteel reinforcing bar that has the head(s) welded.4. Ordering Information4.1
36、 It shall be the responsibility of the purchaser to specify all requirements that are necessary for material ordered to thisspecification. Such requirements shall include but are not limited to the following:4.1.1 Quantity;4.1.2 Name of product: welded, forged, cold-swaged, cold-extruded, ferrous me
37、tal-filled sleeved, or threaded headed bars forthe reinforcement of concrete;4.1.3 Reinforcing bar specification and year of issue;4.1.4 Bar size;4.1.5 Deformed bars;4.1.6 Head geometry, including thickness, diameter or height and width of the head;4.1.7 Head material specification and year of issue
38、 for welded head bars (5.2.1);4.1.8 Bend testing of welded headed bars in sizes No. 11, 14, and 18 36, 43, and 57 (6.4.1);4.1.9 Number of heads per bar length;4.1.10 Length of bar assembly;4.1.11 Packaging;4.1.12 ASTM designation and year of issue; and4.1.13 Optional requirements of Annex A1, if app
39、licable.4.1.14 Optional copy of material test report.5. Material and Manufacture5.1 Reinforcing BarsFor welded headed bars, the reinforcing bars shall conform to Specification A706/A706M. For forgednon-welded headed bars, the reinforcing bars shall conform to Specification A615/A615M or A706/A706M,
40、as specified by thepurchaser.5.2 Heads:5.2.1 The head material shall be selected by the manufacturer.5.3 The head dimensions shall be provided by the purchaser in the order. Head dimensions shall define the head geometryincluding thickness, diameter, or height and width of the head (Fig. 1). Alterna
41、te head dimensions supplied by the manufacturershall be permitted if agreed to in advance by the purchaser. The manufacturer shall furnish documentation to the purchaser, in theform of calculations or test reports, or both, that confirms the suitability of alternate head dimensions for the intended
42、application.NOTE 2Alternate head dimensions resulting in a net bearing area less than four times the nominal cross-sectional area of the deformed reinforcingbar are not suitable for use in construction projects governed by certain consensus building codes and design standards (see 5.4 and Note 3).5.
43、4 When specified by the purchaser in the purchase order or contract as a class HA headed bar, head dimensions shall meetthe requirements of Annex A1.A970/A970M 13a3NOTE 3Some methods of attachment, as defined in Section 3 of this specification, do not meet the requirements on obstructions as prescri
44、bed inAnnexA1. The requirements for head dimensions, limitations to reinforcing bar deformation interruptions and the size of obstruction allowances providedin AnnexA1 are mandated by certain consensus building codes and design standards, for example, “Building Code Requirements for Structural Concr
45、ete(ACI 318).“ Heads with obstructions that do not conform to AnnexA1 may not be permitted for use by certain building codes and design standards, suchas ACI 318.5.5 WeldingA welding procedure conforming to AWS D1.4/D1.4M shall be used for all required production welding of thehead to the bar, excep
46、t for friction welding that shall conform to AWS C6.1 in conjunction with the manufacturers QA/QCprocedures.5.6 ForgingFor integrally forged headed bars, the heads shall be produced by deforming the bar ends in a hot-forging process.5.7 Threading:5.7.1 Threads on bars shall be either tapered or stra
47、ight. The head shall either thread onto the bar directly, or it shall be heldon the bar end by a nut and counternut. Thread specifications and standards shall be selected by the manufacturer.5.7.2 The out-of-roundness in the as-rolled reinforcing bar shall be evaluated so that the manufacturers mini
48、mum threaddimensions are maintained.5.7.3 It shall be permissible to hot- or cold-roll, or machine cut, threads into the surface of the bar and heads at the option ofthe manufacturer.6. Mechanical Test and Performance Requirements6.1 Headed bars shall be subjected to mechanical tests to verify produ
49、ction method and product quality prior to manufacture.Mechanical testing also shall be performed at intervals during production of the assembly.6.2 Tensile Tests:6.2.1 Tensile testing of the headed bar assembly shall be performed in accordance with the requirements described in TestMethods and Definitions A370. The failure mode shall be reported as partial or total fracture of the bar, the head, or the head-to-barconnection.6.2.2 Specimen PreparationTensile test specimens shall be the full cross-section of the bar with a head attached to one endof
