Nonlinear Fastener-Based Modeling of Cold-Formed Steel Shear Walls

As low- and mid-rise construction design objectives push cost-efficient engineering practice to the forefront, cold-formed steel (CFS) has been increasingly used as structural or nonstructural components. The main lateral force resisting system in cold-formed steel construction is shear walls, comprised of chord studs, field studs, all capped in tracks and sheathed or strapped. This study aims to introduce and validate a computational approach capable of demonstrating how oriented strand board (OSB) sheathed CFS framed shear walls behave during lateral loading. A robust three-dimensional finite element model of wood sheathed CFS shear walls is introduced by numerically simulating three different shear wall configurations. The focal points of this work include fastener-based modeling approaches that account for the variability of CFS-to-sheathing fastener behavior. To inform the computational work and address the inherent variability in CFS connection behavior, 30 identical stud-screw-sheathing specimens were tested. The numerical results are validated by recent experimental studies, assessing the efficiency of fastener-based models to accurately capture strength, stiffness, and failure modes of CFS shear walls.