Document: NRC Regulatory Guide
Document ID: 776b9130-d4de-4c44-81a6-ecd8c36df0ca
Document Type: regulatory_guide
Title: Safety-Related Steel Structures and Steel-Plate Composite
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2033/ML20339A558.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.243
CFR Part: 
CFR Title: 

Content:
ability using the direct second-order analysis method is implemented, the stress state at the onset of instability should be confirmed to be in the elastic range to ensure valid results, since it only considers geometric nonlinearities and initial imperfections. 4. ANSI/AISC N690-18, Chapter NI—Design of Composite Members 4.1. The methods for design and construction found in RG 1.142, Revision 3, issued May 2020, should be used as applicable for composite members. 4.2. Consistent with RG 1.142, Revision 3, this RG does not endorse, in general, the use of high-strength reinforcement (yield strength greater than 60,000 pounds per square inch) in design (e.g., ANSI/AISC N690-2018, Chapter NI, on the design of composite members refers to Chapter I of AISC 360-16, which allows the use of high-strength reinforcement). If high-strength reinforcement is used, applicants should demonstrate its adequacy for specific use of the design by testing, analysis, or performance evaluation. 4.3. The following criteria should be used when applying the direct analysis method of design for structural systems that include encased composite members or filled composite members: 4.3.1. The provisions in paragraph I1.5 of AISC 360-16 for stiffness calculations are acceptable if the findings in Denavit et al. (Ref. 24) for stability sensitive structures are addressed and demonstrated not to be applicable. 4.3.2. Long-term effects due to creep and shrinkage should be analyzed. 5. ANSI/AISC N690-8, Chapter NJ—Design of Connections For Chapter NJ, the references in AISC 360-16, Chapter J, to American Concrete Institute (ACI) 318-14, “Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary,” (Ref. 25), Chapter 17, should be replaced with ACI 349-13, “Code Requirements for Nuclear Safety-Related Concrete Structures (ACI 349-13) and Commentary” (Ref. 26), Appendix D, and all other references to ACI 318 should be replaced with ACI 349-13. In addition, requirements