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Are You Properly Specifying Materials?
By martin anderson and charles j. carter, s.e., p.e.

Keeping tabs on available ASTM Specifications for each structural shape will help you make the right choices when designing your projects.
ThE MATERIALS AND PRODUCTS USED IN bUILDINg DESIgN and construction are almost universally designated byreference to an appropriate ASTM specification. This simplifies the design and construction process because you can define all the characteristics of a specified product. However, with dozens of ASTM specifications applicable in steel building construction alone, it can be a challenge to keep the standard designations used in contract documents current. This article provides a summary of the commonASTM specifications used in steel building design and construction, including structural shapes, plate products, fastening products, and other products. This information is based upon similar and more extensive information in the 13th Edition AISC Steel Construction Manual. The reader may also find it convenient to use the recently revised AISC publication Selected ASTM Standards for Structural SteelFabrication 2008, which is a compilation of more than 60 steelrelated ASTM standards. Both of these publications are available for purchase online at www.aisc.org/bookstore. STRUCTURAL ShAPES See the summary in Table 2-1. W-Shapes The preferred material specification for W-shapes is ASTM A992 (Fy = 50 ksi, Fu = 65 ksi). The availability of W-shapes in grades other than ASTM A992 should beconfirmed prior to their specification. W-shapes with higher yield and tensile strength can be obtained by specifying ASTM A572 Grade 60 or 65, or ASTM A913 Grades 60, 65, or 70. W-shapes with atmospheric corrosion resistance (weathering) characteristics can be obtained by specifying ASTM A588 or ASTM A242 Grade 42, 46, or 50. Other material specifications applicable to W-shapes include ASTM A36, ASTMA529 Grade 50 and 55, ASTM A572 Grade 42 and 50, and ASTM A913 Grade 50. M-Shapes and S-Shapes The preferred material specification for M- and S-shapes is in transition. ASTM A36 (Fy = 36 ksi, Fu = 58 ksi) has been traditional, but at least one steel producer now sells these shapes in ASTM A572 Grade 50 (Fy = 50 ksi, Fu = 65 ksi) for a lower price than ASTM A36. During this transition, we suggestyou ask a fabricator what grade is most common when you use these shapes. The availability of M-shapes in other grades should be confirmed prior to their specification. M-shapes with atmospheric corrosion resistance (weathering) can be obtained by specifying ASTM A588 or ASTM A242 Grade 50. Other material specifications applicable to M- and S-shapes include ASTM A572 Grades 42, 55, 60, and 65, ASTMA529 Grades 50 and 55, ASTM A913 Grades 50, 60, 65, or 70, and ASTM A992. Channels The preceding comments for M- and S-shapes apply equally to channels. hP-Shapes The preferred material specification for HP shapes is ASTM A572 Grade 50 (Fy = 50 ksi, Fu = 65 ksi); the availability of other grades should be confirmed prior to specification. HP-shapes with atmospheric corrosion resistance(weathering) can be obtained by specifying ASTM A588 or ASTM A242 Grades 46 or 50. Other material specifications applicable to HP-shapes include ASTM A36, ASTM A529 Grades 50 or 55, ASTM A572 Grades 42, 55, 60, and 65, ASTM A913 Grades 50, 60, 65, and 70, and ASTM A992. Angles The preferred material specification for angles is ASTM A36 (Fy = 36 ksi, Fu = 58 ksi). The availability of angles in grades otherthan ASTM A36 should be confirmed prior to their specification. Angles with higher yield and tensile strength can be obtained by specifying ASTM A572 Grade 42, 50, 55, 60, or 65, ASTM A529 Grades 50 or 55, ASTM A913 Grades 50, 60, 65, or 70, and ASTM A992. Angles with atmospheric corrosion resistance (weathering)

Martin Anderson is coordinator of AISC’s Steel Solutions Center. Charles J. Carter...