Design of Cold-Formed Steel Screw Connections with Gypsum Sheathing at Ambient and Elevated Temperatures

摘要: Load-bearing cold-formed steel (CFS) walls sheathed with double layers of gypsum plasterboard on both sides have demonstrated good fire resistance and attracted increasing interest for use in mid-rise CFS structures. As the main connection method, screw connections between sheathing play an important role structural design this wall system. However, studies mechanical behavior double-layer are still limited. In study, 200 monotonic tests single- or at ambient elevated temperatures were conducted. The failure shear was different from that single-layer temperature, it could be described as breaking loaded edge combined significant tilting flexing fracture. fracture gradually disappear temperatures. addition, influence distance, is discussed detail clear conclusions. A unified formula strength proposed adequate accuracy. simplified load–displacement model post-peak branch developed to evaluate response