1.1 本规范涵盖预应力混凝土施工中使用的两个等级的低松弛七线钢绞线。基于绞线的标称面积，250级[1725]和270级[1860]的最小抗拉强度分别为250 ksi[1725 MPa]和270 ksi[1860 MPa]。 1.2 提供了一个补充要求（S1），用于0.600的粘结强度测试 英寸[15.24 采购商要求使用直径为mm的270[1860]级预应力地锚绞线。补充要求仅在采购订单中有规定时适用。 1.3 本规范的文本包含提供解释性材料的注释和脚注。这些注释和脚注（不包括表中的注释和脚注）不应被视为规范的要求。 1.4 本规范适用于英制单位（如规范A416）或国际单位制单位（如规格A416M）的订单。 1.5 以英寸磅单位或国际单位制表示的数值应单独视为标准。在正文中，国际单位制显示在括号中。每个系统中规定的值可能不是完全相等的；因此，每个系统应独立使用。将两个系统的值组合在一起可能会导致不符合规范。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。

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 [1860] have minimum tensile strengths of 250 ksi [1725 MPa] and 270 ksi [1860 MPa], respectively, based on the nominal area of the strand. 1.2 A supplementary requirement (S1) is provided for use where bond strength testing of 0.600 in. [15.24 mm] diameter Grade 270 [1860] 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 and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables) shall not be considered as requirements of the specification. 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 are shown in brackets. The values stated in each system may not be 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. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.