ASTM A416/A416M-17a pdf download.Standard Specification for Low-Relaxation, Seven-Wire Steel Strand for Prestressed Concrete.
1.1 This specification covers two grades of low-relaxation, seven-wire steel strand for use in prestressed concrete construction. Grade 250 [1725] and Grade 270 11860] have minimum tensile strengths of 250 ksi 11725 MPa and 270 ksi 11860 MPa. respectively, based on the nominal area of the strand.
1.2 A supplementary requirement (SI) is provided for use where bond strength testing of 0.600-in. [15.24-mm] diameter Grade 270 (18601 strand for applications in prestressed ground anchors is required by the purchaser. The supplementary requirement applies only when specifIed in the purchase order.
1 .3 The text of’ this specification contains notes or footnotes, or both, that provide explanatory material. Such notes and footnotes do not contain any mandatory information.
1.4 This specification is applicable for orders in either inch-pound units (as Specification A416) or in SI units (as Specification A416M).
1.5 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units arc shown in brackets. The values stated in each system may not he exact equivalents: therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the specification.
3. Terminology
3.1 Definition of Term Specific to This Specification:
3.1.1 strand, il—a group of wires having a center wire enclosed tightly by six helically placed outer wires with uniform pitch of not less than 12 and not more than 16 times the nominal diameter of the strand.
3.1. 1 . 1 Discussion—The direction of lay is either right- handed or left-handed.
4. Ordering Information
4.1 Orders for low-relaxation seven-wire steel strand under this specification shall contain the following information:
4.1.1 Quantity (feet jmetresj),
4.1.2 Nominal diameter of strand (inches [millimetresi),
4.1.3 Grade of strand, and
4.1.4 ASTM designation A416 [A416M] 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 Relaxation evidence for similarly dimensioned strand of the same grade (6.5. 1),
4.2.2 Specially dimensioned strand (7.4),
4.2.3 Weldiess strand (8.1),
4.2.4 Requirements for outside inspection (11.1),
4.2.5 Load-elongation curve (13.2),
4.2.6 Packaging and package marking (Section 14).
4.2.7 Supplementary Requirement SI, and
4.2.8 Other special requirements, if any.ASTM A416/A416M pdf download.