1、Designation: A910/A910M 10 A910/A910M 12Standard Specification forUncoated, Weldless, 2-2-Wire and 3-Wire Steel Strand forPrestressed Concrete1This standard is issued under the fixed designation A910/A910M; the number immediately following the designation indicates the yearof original adoption or, i
2、n the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers two types and two grades of 2-2-wire and 3-wire, uncoat
3、ed steel strand for use in pretensioned andposttensioned prestressed concrete construction. The two types of strand are low-relaxation and stress-relieved (normal-relaxation).Low-relaxation shall is to be regarded as the standard type. Stress-relieved (normal-relaxation) strand will not be furnished
4、 unlessspecifically ordered, or by arrangement between purchaser and supplier. ordered. The two grades are 1725 (250) and 1860(270).250 1725 and 270 1860. Grades 250 1725 and 270 1860 have minimum tensile strengths of 1725 MPa (250 ksi) and1860 MPa (270 ksi)250 ksi 1725 MPa and 270 ksi 1860 MPa resp
5、ectively, based on the nominal area of the strand.1.2 This specification is applicable for orders in either inch-pound units (as Specification A910) or in SI units (as SpecificationA910M).1.3 The values stated in either inch-pound units or SI units are to be regarded separately as the standard. With
6、in the text, theinch-poundSI units are shown in parentheses.brackets. The values stated in each system are not exact equivalents; therefore, eachsystem mustshall be used independently of the other. Combining values from the two systems may result in nonconformancenon-conformance with the specificati
7、on.2. Referenced Documents2.1 ASTM Standards:Standard:2A1061/A1061M Test Methods for Testing Multi-Wire Steel Strand2.2 U.S. Military Standards:Standard:3MIL-STD-129 Marking for Shipment and StorageMIL-STD-163 Steel Mill Products Preparation for Shipment and Storage2.3 Federal Standards:Standard:3Fe
8、d. Std. No. 123 Marking for Shipments (Civil Agencies)3. Terminology3.1 DefinitionsDefinition of TermsTerm Specific to This Standard:Specification:3.1.1 strand, nall strands shall be comprised of either two wires Either two or three wires helically wound around each other;they shall have a other wit
9、h uniform pitch of not less than 12 nor and not more than 16 times the nominal diameter of the strand.3.1.1.1 DiscussionThe direction of lay may be either right- or left-hand; however, strands of different lays should not be spliced together.3.1.2 DiscussionThe direction of lay may be either right o
10、r left hand; however, strands of different lays shall not be splicedtogether.1 This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.05on Steel Reinforcement.Current edition approved April
11、1, 2010Nov. 15, 2012. Published July 2010December 2012. Originally approved in 1992. Last previous edition approved in 20052010 asA910/A910M 05.A910/A910M 10. DOI: 10.1520/A0910_A0910M-10.10.1520/A0910_A0910M-12.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM C
12、ustomer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/
13、www.access.gpo.gov.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that user
14、s consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM 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 Conshoh
15、ocken, PA 19428-2959. United States14. Ordering Information4.1 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 (meters feet)
16、,(feet metres),4.1.2 Diameter Nominal diameter and description of strand (Section (Table 17),4.1.3 Number of wires (2 or 3),4.1.4 Grade of strand (see Grade,1.1 and Table 1 and Table 2),4.1.5 Type of strand (see(low-relaxation 1.1 andor stress-relieved Table 2),(normal relaxation),4.1.6 Inspection (
17、11.1),4.1.7 Load-elongation curve (13.2),4.1.8 Packaging (Section (1414.1), and4.1.9 ASTM designation and year of issue, andissue.4.1.8 Special requirements, if any.NOTE 1A typical ordering description is as follows: 100 000 m (325 000 ft) of 6.2 mm (0.244 in.) diameter, three wire, Grade 1860 MPa (
18、270 ksi),low-relaxation strand in 10 000 m (32 500 ft) reelless packs conforming to ASTM A910/A910MXX.5. Materials and Manufacture5.1 Base MetalThe base metal shall be carbon steel of such quality that when drawn to wire, fabricated into strand and thenthermally treated, it shall have the properties
19、 and characteristics prescribed in this specification.5.2 WireThe wire from which the strand is to be fabricated shall be round and have a dry-drawn finish.TABLE 1 Breaking Strength RequirementsDescription and Diameter of Strand Breaking Strength ofStrandSteel Area ofStrandWeight ofStrandin. mmDescr
20、iption NominalDiameter Description NominalDiameter lbf kN in.2 mm2 lbs/1000 ft kg/1000 mGRADE 250 (1725 MPa)2 0.114 0.228 2 2.90 5.8 5000 22.2 0.020 13.2 69.9 104.03 0.089 0.189 3 2.25 4.8 4750 21.1 0.019 12.0 63.3 94.23 0.095 0.205 3 2.40 5.2 5250 23.4 0.021 13.6 71.9 107.03 0.114 0.244 3 2.90 6.2
21、7750 34.5 0.031 19.8 104.0 155.03 0.118 0.256 3 3.00 6.5 8250 36.7 0.033 21.3 112.0 167.03 0.138 0.295 3 3.50 7.5 11 250 50.0 0.045 29.0 153.0 228.03 0.158 0.340 3 4.00 8.6 14 500 64.5 0.058 37.4 200.6 298.4GRADE 270 (1860 MPa)2 0.114 0.228 2 2.90 5.8 5400 24.0 0.020 13.2 69.9 104.03 0.089 0.189 3 2
22、.25 4.8 5130 22.8 0.019 12.0 63.3 94.23 0.095 0.205 3 2.40 5.2 5670 25.2 0.021 13.6 71.9 107.03 0.114 0.244 3 2.90 6.2 8370 37.2 0.031 19.8 104.0 155.03 0.118 0.256 3 3.00 6.5 8910 39.6 0.033 21.3 112.0 167.03 0.138 0.295 3 3.50 7.5 12 150 54.0 0.045 29.0 153.0 228.03 0.158 0.340 3 4.00 8.6 15 660 6
23、9.7 0.058 37.4 200.6 298.4TABLE 1 Breaking Strength RequirementsDescription and Nominal Diameter of Strand Breaking Strength ofStrandSteel Area ofStrandWeight Mass ofStrandin. mmDescription NominalDiameter Description NominalDiameter lbf kN in.2 mm2 lbs/1000 ft kg/1000 mGRADE 250 1725 MPa2 0.114 0.2
24、28 2 2.90 5.8 5000 22.2 0.020 13.2 69.9 104.03 0.089 0.189 3 2.25 4.8 4750 21.1 0.019 12.0 63.3 94.23 0.095 0.205 3 2.40 5.2 5250 23.4 0.021 13.6 71.9 107.03 0.114 0.244 3 2.90 6.2 7750 34.5 0.031 19.8 104.0 155.03 0.118 0.256 3 3.00 6.5 8250 36.7 0.033 21.3 112.0 167.03 0.138 0.295 3 3.50 7.5 11 25
25、0 50.0 0.045 29.0 153.0 228.03 0.158 0.340 3 4.00 8.6 14 500 64.5 0.058 37.4 200.6 298.4GRADE 270 1860 MPa2 0.114 0.228 2 2.90 5.8 5400 24.0 0.020 13.2 69.9 104.03 0.089 0.189 3 2.25 4.8 5130 22.8 0.019 12.0 63.3 94.23 0.095 0.205 3 2.40 5.2 5670 25.2 0.021 13.6 71.9 107.03 0.114 0.244 3 2.90 6.2 83
26、70 37.2 0.031 19.8 104.0 155.03 0.118 0.256 3 3.00 6.5 8910 39.6 0.033 21.3 112.0 167.03 0.138 0.295 3 3.50 7.5 12 150 54.0 0.045 29.0 153.0 228.03 0.158 0.340 3 4.00 8.6 15 660 69.7 0.058 37.4 200.6 298.4A910/A910M 122NOTE 1This product is a composite of two or three wires and is produced to mechan
27、ical properties only, only to meet the prescribed mechanicalproperties, of which the chemical composition of all wires or any individual wire is not pertinent to this application, and heat identity is not necessarilymaintained. It is possible that wire from more than one heat may be used in the manu
28、facture of a reel or reelless pack. Traceability is based on pack identitythe identity of reels or reelless packs as maintained and reported by the manufacturer.5.3 TreatmentAfter stranding, low-relaxation strand shall be subjected to a continuous thermo-mechanical treatment toproduce the prescribed
29、 mechanical properties. For stress-relieved (normal-relaxation) strand, only thermal treatment is necessary.Temper colors that result from the stress-relieving operation are considered normal for the finished appearance of this strand.6. Mechanical Properties Property Requirements6.1 Tests for mecha
30、nical properties shall be conducted in accordance with Test Methods A1061/A1061M. Low-relaxation strandshall also be tested as prescribed in Test Methods A1061/A1061M.6.2 Breaking StrengthThe breaking strength of the finished strand shall conform to the requirements prescribed in Table 1.6.3 Yield S
31、trengthYield strength in kN (lbs)lbs kN shall be measured at 1 % extension under load. load in accordance withthe test procedure delineated in Test Methods A1061/A1061M, Section 9.1. The minimum yield strength shall be 90 % forlow-relaxation strand and 85 % for stress-relieved (normal relaxation) (n
32、ormal-relaxation) strand of the breaking strength listed inTable 1. Initial loads for the test and minimum yield strengths are listed in Table 2.6.3.1 The extension under load shall be measured by an extensometer calibrated with the smallest division not larger than0.0001 in./in. 0.0001 mm/mm of gag
33、e length.6.4 ElongationThe total elongation under load shall be determined in accordance with Test Methods A1061/A1061M, Section9.2. The total elongation under load shall not be less than 3.5 %. 3.5 % using a gage length of not less than 24 in. 600 mm. ItTABLE 2 Yield Strength RequirementsDescriptio
34、n and Diameter of StrandInitial LoadMinimum Load at 1 % Extensionin. mm Stress-Relieved(Normal Relaxation) Low RelaxationDescription NominalDiameter Description NominalDiameter lbf kN lbf kN lbf kNGRADE 250 (1725 MPa)2 0.114 0.228 2 2.90 5.8 500 2.2 4250 18.9 4500 20.03 0.089 0.189 3 2.25 4.8 475 2.
35、1 4038 18.0 4275 19.03 0.095 0.205 3 2.40 5.2 525 2.3 4463 20.0 4725 21.03 0.114 0.244 3 2.90 6.2 775 3.5 6588 29.3 6975 31.03 0.118 0.256 3 3.00 6.5 825 3.7 7013 32.2 7425 33.03 0.138 0.295 3 3.50 7.5 1250 5.0 9563 42.5 10 125 45.03 0.158 0.340 3 4.00 8.5 1450 6.5 12 325 54.8 13 050 11.7GRADE 270 (
36、1860 MPa)2 0.114 0.228 2 2.90 5.8 540 2.4 4590 20.4 4860 21.63 0.089 0.189 3 2.25 4.8 513 2.3 4360 19.4 4617 20.53 0.095 0.205 3 2.40 5.2 567 2.5 4820 21.4 5103 22.73 0.114 0.244 3 2.90 6.2 837 3.7 7115 31.6 7533 33.53 0.118 0.256 3 3.00 6.5 891 4.0 7574 33.7 8019 36.03 0.138 0.295 3 3.50 7.5 125 5.
37、4 10 328 45.9 10 125 45.03 0.158 0.340 3 4.00 8.6 566 7.0 13 311 59.2 14 094 62.7TABLE 2 Yield Strength RequirementsDescription and Nominal Diameter of StrandInitial LoadMinimum Load at 1 % Extensionin. mm Stress-Relieved(Normal-Relaxation) Low-RelaxationDescription NominalDiameter Description Nomin
38、alDiameter lbf kN lbf kN lbf kNGRADE 250 1725 MPa2 0.114 0.228 2 2.90 5.8 500 2.2 4250 18.9 4500 20.03 0.089 0.189 3 2.25 4.8 475 2.1 4038 18.0 4275 19.03 0.095 0.205 3 2.40 5.2 525 2.3 4463 20.0 4725 21.03 0.114 0.244 3 2.90 6.2 775 3.5 6588 29.3 6975 31.03 0.118 0.256 3 3.00 6.5 825 3.7 7013 32.2
39、7425 33.03 0.138 0.295 3 3.50 7.5 1250 5.0 9563 42.5 10 125 45.03 0.158 0.340 3 4.00 8.5 1450 6.5 12 325 54.8 13 050 11.7GRADE 270 1860 MPa2 0.114 0.228 2 2.90 5.8 540 2.4 4590 20.4 4860 21.63 0.089 0.189 3 2.25 4.8 513 2.3 4360 19.4 4617 20.53 0.095 0.205 3 2.40 5.2 567 2.5 4820 21.4 5103 22.73 0.1
40、14 0.244 3 2.90 6.2 837 3.7 7115 31.6 7533 33.53 0.118 0.256 3 3.00 6.5 891 4.0 7574 33.7 8019 36.03 0.138 0.295 3 3.50 7.5 125 5.4 10 328 45.9 10 125 45.03 0.158 0.340 3 4.00 8.6 566 7.0 13 311 59.2 14 094 62.7A910/A910M 123shall be permissablepermissible to determine the total elongation value by
41、adding to the 1.0 % yield extension the percentextension or movement between the jaws gripping the strand after yield determination. The percent is calculated on the new baselength of jaw-to-jaw distance.6.5 Relaxation PropertiesLow-relaxation strand shall have relaxation losses of not more than 2.5
42、 % when initially loaded to70 % of specified minimum breaking strength or not more than 3.5 % when loaded to 80 % of specified minimum breaking strengthof the strand after 1000 h tested under conditions listed in 6.5.1 throughaccordance with 6.5.7.the specific procedures in TestMethods A1061/A1061M,
43、 Section 9.4.6.5.1 If required, relaxation evidence shall be provided from the manufacturers records of tests on similarly dimensioned strandof the same grade.6.5.2 The temperature of the test specimen shall be maintained at 20 6 2C (68 6 3.5F).6.5.3 The test specimen shall not be subjected to loadi
44、ng prior to the relaxation test.6.5.4 The initial load shall be applied uniformly over a period of not less than 3 min and not more than 5 min and the gage lengthshall be maintained constant; load-relaxation readings shall commence 1 min after application of the total load.6.5.5 Overstressing of the
45、 test specimen during the loading operation shall not be permitted.6.5.6 The duration of the test shall be 1000 h or a shorter computed period extrapolated to 1000 h that can be shown by recordsto provide similar relaxation values.6.5.7 The test gage length shall be at least 60 times the nominal dia
46、meter of the strand. If this gage length exceeds the capacityof the extensometer or the testing machine, then it is permitted to substitute a minimum gage length of 40 times the nominaldiameter of the strand.7. Dimensions and Permissible Variations7.1 The size of the finished strand shall be express
47、ed as the nominal diameter of the strand as decimal fraction of an inch.inin. mm.7.2 Variations in individual wire diameters shall not be cause for rejection provided that the other requirements of thisspecification are met.7.3 Specially-Dimensioned Strand:7.3.1 It shall be permitted to furnish, und
48、er this specification, strands with nominal diameters that are different than those listedin Table 1 and Table 2. The breaking strength shall be defined, and the yield strength, as defined in 6.3, shall not be less than 90 %and 85 % of the specified minimum breaking strength for low-relaxation and stress-relie
