AASHTO M 322M/M 322-10 (2019)

This specification covers rail-steel and axle-steel bars for concrete reinforcement. Three types of product are included, designated with a “rail symbol” and an “R” for bars made of rail-steel and with an “A” for bars made of axle-steel. The standard sizes and dimensions of deformed bars and their number designations are given in Table 1. All sizes and grades of all types may not be readily available; manufacturers should be consulted to verify availability.

Type “rail symbol” and Type R are of two minimum yield levels, namely 350 MPa [50,000 psi] and 420 MPa [60,000 psi], designated as Grade 350 [50] and Grade 420 [60], respectively. Type A is of two minimum yield levels, namely 300 MPa [40,000 psi] and 420 MPa [60,000 psi], designated as Grade 300 [40] and Grade 420 [60].

The weldability of the steel is not a requirement of this specification.

This specification is applicable for orders in either SI units (M 322M) or inch-pound units (M 322). The values stated in either SI units or inch-pound units are to be regarded as standard. Within the text, the inch-pound units are shown in brackets. The values stated must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.