【国外标准】 Standard Specification for Steel Strand, Indented, Seven-Wire Stress-Relieved for Prestressed Concrete

This specification covers seven-wire uncoated, indented, stress-relieved carbon steel strands for use in pre-stressed concrete construction. Wire dimensions, indentations, and mechanical properties shall be in accordance to the values specified in this specification. The carbon steel strand is produced to satisfy only the specified mechanical properties, this specification contains no information on the chemical composition of the wires.1.1 This specification covers two types and two grades of indented seven-wire uncoated, steel strand for use in prestressed concrete construction. The two types of strand are low-relaxation and stress-relieved (normal-relaxation). Grade 250I [1725I] and Grade 270I [1860I] 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 This specification is applicable for orders in either inch-pound units (as Specification A886) or in SI units (as Specification A886M).1.3 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 are not 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.1.4 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.