Steel-plate composite walls: Experimental database and design for out-of-plane shear

• Database of SC beam shear experiments is compiled and compared with design codes.
• Shear strength decreases with increasing shear span-to-depth ratio and section depth.
• Lower bound shear strength occurs for shear span-to-depth ratios of 3.0–3.5.
• ACI code equations conservatively estimate SC wall out-of-plane shear strength.
• Strength reduction (ϕ) factors are recommended for use with design equations.

The seismic behavior and design of steel-plate composite (SC) walls in safety-related nuclear facilities is typically governed by their in-plane shear strength and ductility. However, the out-of plane shear (and flexure) behavior can govern the design near foundations and connections where SC walls interact with other structures. The out-of-plane shear behavior of SC walls is similar to that of reinforced concrete (RC) walls, and has been evaluated experimentally by conducting beam tests in one-way bending. The beam tests were conducted on specimens that were representative of strips taken in the longitudinal and transverse directions of full-scale SC walls. This paper includes a summary of the experimental database of SC beam shear tests conducted in Japan, S. Korea, China and the US. Different loading configurations were used to test the SC beam specimens. The parameters considered were the shear span-to-depth ratio, steel faceplate thickness (reinforcement ratio), stud anchor spacing, and the presence (or absence) of shear reinforcement. The out-of-plane shear strengths from the tests in the experimental database are summarized and compared with shear strength calculations based on applicable design code equations to estimate the lower bound design shear strength of SC walls. Reliability analysis is conducted to suggest associated strength reduction (ϕ) factors.