Cold-formed steel is lightweight, strong, and fire resistant, making it a popular choice in construction, particularly for low-rise and mid-rise buildings. Extremely durable and versatile, CFS is a cost-effective material that is environmentally friendly and resilient. Despite these benefits, there has been limited adoption of CFS mainly due to knowledge gaps regarding its seismic performance. The use of CFS sheets as sheathing is relatively new, and most testing has been limited. Additionally, the understanding of CFS wall-line structural behavior, particularly the contribution from non-designated systems such as gravity walls, under seismic events remains limited.
Researchers Amanpreet Singh, Xiang Wang, Zhidong Zhang, Fani Derveni, Hernan Castaneda, Kara D. Peterman, Benjamin W. Schafer, and Tara C. Hutchinson conducted experiments to document the performance of steel sheet sheathed CFS-framed wall assemblies. In their study, “Steel Sheet Sheathed Cold-Formed Steel Framed In-line Wall Systems. I: Impact of Structural Detailing” in the Journal of Structural Engineering, the authors employed a two-phased program. In phase one, pairs of eight shear walls were tested on the Natural Hazards Engineering Research Infrastructure large high-performance outdoor shake table, and 10 single wall-line configurations were used in phase two at the University of California, San Diego, Structural Engineering Powell Laboratory. Learn more about their efforts to characterize the performance of long CFS-framed walls, particularly for mid-rise to high-rise construction at https://doi.org/10.1061/(ASCE)ST.1943-541X.0003433. The abstract is below.
Abstract
The North American construction industry has seen substantial growth in the use of cold-formed steel (CFS) framing for midrise buildings in recent years. In seismic zones, CFS-framed buildings utilize shear walls to provide the primary lateral resistance to earthquake induced loads. Although oriented strand board (OSB) and plywood panels have been traditionally used as the sheathing material for these essential components, more recently, steel sheet sheathing has emerged as a novel strategy due to its strength, ductility, ease of installation, and use of noncombustible material, among other benefits. To address the paucity of data regarding CFS-framed shear wall response within actual wall lines of buildings, a two-phased experimental effort was conducted. Wall-line assemblies were fabricated and tested with shear walls placed in-line with gravity walls. The shear walls chord stud packs include tie-rod assemblies consistent with multi-story detailing. Specimens were either unfinished or finished, and the shear walls were laid out in a symmetrical or unsymmetrical fashion within in the wall line. 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 structural detailing of CFS-framed walls are quantified through dynamic and quasi-static tests, and a companion paper presents findings regarding the impact of architectural variations on seismic performance.
Review the test results in the ASCE Library: https://doi.org/10.1061/(ASCE)ST.1943-541X.0003433.
