Minimum Requirements and Section Detailing Provisions for Steel-Plate Composite (SC) Walls in Safety-Related Nuclear Facilities

Steel-plate composite (SC) walls are comprised of concrete walls sandwiched between steel faceplates located on the exterior surfaces. These faceplates are anchored to the concrete infill using steel anchors and connected to each other using ties. SC walls have been used extensively in the third generation of nuclear power plants and are also being considered for small modular reactors (SMRs) of the future. The American Institute of Steel Construction (AISC) has published Supplement No. 1 to AISC N690, which includes Appendix N9 for the design of SC walls in safety-related nuclear facilities. This paper presents the minimum requirements for SC walls and the section detailing provisions from Appendix N9 along with their basis. The minimum requirements include requirements for minimum and maximum SC wall thickness, faceplate thickness, and steel and concrete material strengths. The provisions of Appendix N9 are applicable to SC walls that satisfy these minimum requirements. The design provisions account for the effects of interaction between out-of-plane shear demands (in both x- and y-directions) and the corresponding interfacial shear demands while accounting for the differences in behavior between yielding and nonyielding steel anchors and ties as classified by AISC N690 Supplement No. 1.