Steel Sheet Sheathed Cold-Formed Steel Framed In-line Wall Systems. II: Impact of Nonstructural Detailing

Abstract

Although cold-formed steel (CFS) framing systems have the potential to support the need for resilient housing, the use of CFS has been restricted due to gaps in understanding its structural behavior and by the limited guidelines provided in design standards. In particular, the contribution from nondesignated lateral systems and portions of the building system not specifically designated by the design engineers has not been substantially investigated through experiments. To address these shortcomings, a two-phased experimental effort was undertaken to assess the impact of gravity walls, finish application, window openings, and their relationship with the designated lateral force-resisting system. The wall-line assemblies tested, which have shear walls placed in-line with gravity walls, adopted chord stud packs with a tie-rod assembly and were either unfinished or finished, and laid out in a symmetrical or unsymmetrical fashion. In addition, both Type I and Type II shear wall and anchorage detailing were investigated. In this paper, the impact of test variables governing the nonstructural detailing of CFSframed walls has been quantified, and a companion paper presents findings regarding the impact of structural detailing.

Steel Sheet Sheathed Cold-Formed Steel Framed In-line Wall Systems. I: Impact of Structural Detailing

“…Outcomes pertaining to the impact of structural detailing design variables on wall performance add valuable information to the ongoing development of seismic systems for buildings framed with CFS. Similarly, the companion paper (Singh et al 2022b) explores the impact of nonstructural detailing on steel sheet sheathed CFS wall-lines and provides insight into the effects of architectural finishes and window openings on wall performance.…”

“…Installed gypsum boards were 1.22-m (4-ft) × 2.44-m (8-ft) × 16-mm (5=8in:) Firecode Type X, and glass-mat sheathing panels were 1.22-m (4-ft) × 2.74-m (9-ft) × 16-mm (5=8in:) Firecode Type X. Singh et al (2022b) provides a description of the steps involved in the finish application.…”

“…Complementing the analog sensors, five high-resolution cameras also recorded the wall response during the tests. Further details regarding the quasi-static cyclic test program are available in Singh and Hutchinson (2022).…”

“…In particular, the impact of detailing such as tie-down and anchorage system on wall behavior has been quantified through a series of dynamic and quasi-static tests. In a companion paper (Singh et al 2022b), the impact of detailing such as window opening and unsymmetrical shear wall layout on steel sheet sheathed CFS wall-lines are the focus. Usually ignored in design applications, the beneficial effects of nonstructural finish application on several wall performance metrics are also discussed in detail in the companion paper.…”

“…Usually ignored in design applications, the beneficial effects of nonstructural finish application on several wall performance metrics are also discussed in detail in the companion paper. Interested readers are referred to Singh et al (2022b) to understand the effects of architectural/nonstructural details, which form a significant portion of the current research findings.…”