AASHTO M 270M/M 270-09

This specification covers carbon and high-strength low-alloy steel structural shapes, plates, and bars and quenched-and-tempered alloy steel for structural plates intended for use in bridges. Nine grades are available in four yield strength levels.When the steel is to be welded, it is presupposed that a welding procedure suitable for the grade of steel and intended use or service will be utilized. See Appendix X3 of M 160M/M 160 for information on weldability.