ASTM A779 / A779M

Abstract

This specification covers seven-wire, uncoated, compacted, stress-relieved steel strand for prestressed concrete. The chemical requirements, mechanical requirements, and dimensions and permissible variations are presented. The mechanical requirement includes breaking strength, load at 1% extension and elongation. Different test method shall be performed on the strand that includes dimension test, breaking strength test, load at 1% extension test, elongation test and workmanship.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

1.1 This specification covers two types and three grades of compacted, seven-wire, uncoated strand for use in prestressed concrete construction. The two types of strand are low-relaxation and stress-relieved (normal-relaxation). The three grades are 245 [1700], 260 [1800] and 270 [1860].

1.2 This specification is applicable for orders in either inch-pound units (as Specification A779) or in SI units (as Specification A779M).

1.3 The values stated in either inch-pound or SI units are to be regarded 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.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.