AISI to develop new unified cold-formed steel seismic design standard

WASHINGTON, D.C. – The American Iron and Steel Institute (AISI) Standards Council has approved the development of a unified cold-formed steel seismic design standard that will create a new standard: AISI S400, North American Standard for Seismic Design of Cold-Formed Steel Structural Systems. This new standard will provide a platform for the growth of new cold-formed steel seismic force-resisting systems. It will be developed and maintained by the AISI Committee on Framing Standards’ (COFS) Lateral Design Subcommittee. The development of the standard was approved by the AISI Standards Council on March 14, 2013.

AISI currently maintains two standards that address the seismic design of cold-formed steel assemblies: AISI S213, North American Standard for Cold-Formed Steel Framing — Lateral Design, which addresses the design and installation of cold-formed steel light-framed shear walls, diagonal strap bracing (that is part of a structural wall) and diaphragms to resist wind, seismic and other in-plane lateral loads; and AISI S110, Standard for Seismic Design of Cold-Formed Steel Structural Systems — Special Bolted Moment Frames. These two standards are maintained under separate committees, which has complicated the development and approval process and created confusion for users. The new AISI S400 standard will include all of AISI S110 and just the high seismic portions of AISI S213. The remaining portions of AISI S213 will be included in the new AISI S240, North American Standard for Cold-Formed Steel Structural Framing.

These changes also facilitate the consolidation of the AISI Committee on Specifications’ (COS) Seismic Design Subcommittee into the AISI Committee on Framing Standards’ (COFS) Lateral Design Subcommittee. “Focusing our high seismic design applications into one standard will provide both internal and external benefits. Internally, it will consolidate subcommittees, focus expertise, and provide a platform to create new cold-formed steel seismic force-resisting systems,” Jay Larson, P.E., F.ASCE, managing director, AISI Construction Technical Program, said. “Externally, it will streamline the approval process, allowing necessary review by the National Earthquake Hazards Reduction Program (NEHRP) membership and coordination with ASCE 7 and the National Building Code of Canada without holding up the development of non-seismic-related provisions for cold-formed steel. Users will benefit from having the information consolidated into one standard.”

In conjunction with this new charge and expanded scope, the AISI COFS Lateral Design Subcommittee is seeking new committee members to participate in the AISI S400 standard development process. It is expected that the first edition of AISI S400 will be developed by the end of 2013, and the first ballot for the document will likely be issued before July 2013. While the first edition will focus mainly on rearranging the existing provisions into the new format, interested parties are encouraged to be involved as early as possible. For more information on membership on the AISI COFS Lateral Design Subcommittee, please contact the committee secretary, Helen Chen, Ph.D., P.E., LEED AP (hchen@steel.org).