1.1 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. Seven grades are available in four yield st 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. Heat analysis shall be used to determine the percentage of c