Steel-Plate Composite Walls with Different Types of Out-of-Plane Shear Reinforcement: Behavior, Analysis, and Design

Steel-plate composite (SC) walls consist of two steel faceplates connected with tie bars and then filled with concrete. The tie bars provide stability to the empty modules and serve as out-of-plane shear reinforcement after the concrete sets. The tie bars used in SC wall design can vary significantly, for example, round bars, rectangular bars, channel sections, or diaphragm plates. This paper presents the results of experimental and computational investigations conducted to evaluate the out-of-plane shear behavior of SC walls with four different types of tie bars or shear reinforcement. The experimental program consisted of ten full-scale out-of-plane shear tests. The parameters included were the section depth, steel faceplate thickness, shear span-to-depth ratio, longitudinal reinforcement ratio, and shear reinforcement ratio. The experimental results are presented in detail, including response plots pertaining to various displacements, rotations, and strain measurements, along with discussions of concrete cracking and shear reinforcement yielding behavior up to failure. The experimental strengths obtained from this study, combined with tests performed by researchers outside the US, indicated that the current AISC N690 code equations are appropriate for estimating the out-of-plane shear strength of SC wall designs that have different types of shear reinforcement. This paper also includes recommendations for improving and optimizing the strength calculations for special SC wall design cases that are not adequately addressed by the current code provisions. Observations from the experimental results were further supported by three-dimensional (3D) finite-element analyses conducted using benchmarked numerical models. This benchmarked numerical modeling approach is recommended for obtaining additional insight into the out-of-plane shear behavior and conducting numerical parametric studies.