The 2018 version of the AISC standard, Specification for Safety-Related Steel Structures for Nuclear Facilities (ANSI/AISC N690-18), is now available for free download at www.aisc.org/standards. The updated standard includes changes that are compatible with the baseline document, the 2016 AISC Specification for Structural Steel Buildings (ANSI/AISC 360-16), and it replaces ANSI/AISC N690-12 including Supplement No. 1 (ANSI/AISC N690s1-15).
"New provisions in this version of the standard include acceptable methods to design for impactive and/or impulsive loadings, and ductility ratios for steel plate structures," explained Ronald Janowiak, chairman of the AISC Task Committee on Nuclear Facilities that developed the updated standard. "Also, to facilitate welded construction, welds on safety-related material are required to be uniquely identified and traceable. Several new User Notes provide design guidance, including help with establishing material properties when designing for impactive and/or impulsive loads, addressing thermal loads from abnormal load conditions, and guidance for visual weld acceptance criteria."
The new standard has been approved by the AISC Committee on Specifications and is ANSI-accredited.