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ASTM
A911/A911M-21
Standard Specification for Low-Relaxation Steel Bars for Prestressed Concrete Railroad Ties
2021
4
ASTM Vol.01.04 (2022)
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.