【国外标准】 Standard Specification for Low-Relaxation Steel Bars for Prestressed Concrete Railroad Ties

This specification covers uncoated, stress-relieved steel bars for prestressed concrete railroad ties. Analysis of the steel shall conform to the chemical requirements specified by the specification. Mechanical requirements including test method, tensile strength, yield strength, elongation and wrapping test are provided. One test specimen each for the tensile test and the wrapping test shall be taken for every 10 coils or fraction thereof in a lot.1.1 This specification covers low-relaxation steel bars for use in prestressed concrete railroad ties.1.2 This specification is applicable for orders in either inch-pounds units (as Specification A911) or in SI units (as Specification A911M).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 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.1.4 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.