الفهرس | Only 14 pages are availabe for public view |
Abstract Cold-formed steel (CFS) sections offer many benefits in construction, such as a high strength-to-weight ratio, ease of handling, transportation, and erection. Therefore, CFS thin-walled sections are applicable in a wide range of light and moderate buildings. Their range of applications has rapidly expanded from being mainly used as secondary members in steel structures to increasing use as key members. The CFS thin-walled members become part of vertical elements and lateral load-resisting systems. However, the CFS thinwalled Zee section is rarely investigated as a part of the structural system. Also, CFS must be investigated for its capability for energy dissipation, strength deterioration, or stiffness degradation when supporting cyclic loads. This research aims to investigate the axial compression and interaction of axial-flexural mechanical behavior of the CFS Zee sections under monotonic and cyclic loading. The studies were conducted by experimental investigation and numerical analysis, with parametric studies using the Finite Element Model (FEM). The experimental program was conducted for full-scale specimens. The CFS thinwalled Zee section (200Z2) is used, which has a depth of 200mm and a thickness of 2 mm. The Zee section was analyzed using the Direct Strength Method (DSM) to investigate the buckling modes, the resultant stresses, and the section capacity. The specimen’s length was chosen to examine the three individual buckling failure modes: Local buckling (LC), Distortion buckling (DS), and Global buckling (GL) modes with lengths: 600 mm, 1000 mm, and 2500 mm, respectively. The Zee-section with web notch was used in the Distortion and Global buckling specimens to prevent the local buckling occurrence in the web. Manual instruments and 3D scanning captured the imperfection and deviation of the 200Z2 section before testing and which were implemented it in the FEMs. |