Concrete-filled L-shaped steel tube columns can be used to save architectural space at room corners, and may have many advantages of structural behavior of common concrete-filled steel tubes as columns. In this paper, the seismic behavior of concrete-filled L-shaped steel tube columns (CFLSTs) was investigated. Six specimens subjected to a constant axial load and cyclically varying lateral loading were tested to study the effects of width to depth ratio of section, depth to thickness ratio of steel tube and axial load level on the strength, as well as stiffness, ductility and energy dissipation of CFLST columns. Experimental results showed that the displacement ductility of CFLST columns decreased significantly with the increase of axial load level, and the strength and stiffness degradations of CFLST columns were more significant with higher axial load level. With the increase of depth-thickness ratio of steel tube and depth-width ratio of section, the ductility and the lateral ultimate load-carrying capacity of CFLST columns also decreased gradually. All CFLST columns exhibited favorable energy dissipation and ductility, even for the columns subjected to high axial load, which indicates that this type of composite columns is adoptable in practical engineering, especially in seismic regions.

The paper presents experimental and numerical investigation of cold-formed steel (CFS)–framed walls sheathed with corrugated steel sheets. The new wall technology is considered as an alternative shear wall configuration for midrise buildings at strong earthquake and high-wind regions because of its attributes of noncombustibility and higher structural performance than the conventional shear wall types. However, design provisions of such corrugated sheathed CFS-framed shear walls have not been included in the current design standards. To establish comprehensive database information and to observe the performance of the bearing wall for the first time, a test program of full-scale wall assemblies using corrugated steel sheathing was conducted. The test specimens included both shear wall specimens and bearing wall specimens under lateral and vertical/gravity loading. In accordance with the full-scale tests, a numerical model was developed in a computer program, and seismic performance assessment was ...

Cold-formed thin-walled steel residential building systems, because of their good environment protection, seismic performance, and high construction efficiency, have been widely used in the United States, Canada, Japan, and Australia, and recently, they also have had good application in China. Although a variety of studies have been carried out all over the world in the last 20 years, there is no related design code for this kind of building in China. For this reason, a series of research has been conducted in China recently, considering the consistency of standard systems in structural design in China and the newest development in the world. The contents of the paper can be divided into two parts. First, the major research works conducted by the authors over the last 5 years and the main findings are reviewed and summarized. Second, based on a Chinese professional standard, a brief summary of the design methods for cold-formed thin-walled steel framing residential buildings developed by the autho...

Cold-formed steel shear wall with corrugated sheet steel sheathing is a newly proposed lateral force resisting system from recent research work. The advantages of noncombustibility, high shear strength and high shear stiffness enable this new wall system to be a feasible solution for low- and midrise construction at high wind and seismic zones. The design provisions for this new type of shear wall have not been developed in current design specifications. The initial phase of this research project involved the displacement-based testing of bearing wall and shear wall specimens under combined lateral and gravity loading. The phase two research, presented here, includes the nonlinear finite element analysis and the performance evaluation of a set of light framed steel buildings using the corrugated sheet sheathed shear walls. Incremental dynamic analyses were performed on six archetype buildings and seismic performance assessment was evaluated. The results verify a set of seismic performance factors ($R=C_d=6.5$ and $\mathrm{\Omega }=3.0$ ) for the corrugated sheet sheathed shear wall systems.

This research proposes a beam-column hinged joint with additional replaceable energy-dissipating elements, which is highly industrialized and fully fabricated. In this structure, steel beam and steel column are hinged with pins, at which corners a replaceable energy dissipation element is added. The energy dissipation element is rigidly connected to the steel column through a section of H-beam and high-strength bolts and is hinged to the steel beam using high-strength bolts. The main materials, such as energy dissipation elements, steel columns, and steel beams, are all steel with a design yield strength of 345 MPa. Under the condition that the vertical clear distance between the energy dissipation element and the steel beam is constant at 0.2 m, and the size and section of the beams and columns remain unchanged, six groups of different test samples are constructed by changing the thickness and the horizontal length of the energy-dissipating element. Through the experimental research and numerical simulation of 6 groups of specimens, the strength, stiffness, ductility, hysteresis curve, energy dissipation coefficient, equivalent viscous damping coefficient, and failure mechanism of the joints are obtained, and the horizontal section of the energy dissipation element is mainly analyzed. The effects of parameters such as the ratio of length to span and its ratio to the linear stiffness of steel beams on the seismic performance of the joints were compared with those of traditional welded steel frame beam-column joints. The research results show that the joints can be fully assembled, the energy-consuming components can be replaced, and the beam-column connection joints can be controlled in practical applications. The deviation between the experimental results and the numerical simulation results is less than 10%, which is in good agreement. The failure mode of the node conforms to the seismic performance concept of “energy-dissipating elements are destroyed first and easily replaced after earthquakes”; when the ratio of the horizontal length to the span of the energy-consuming components is 0.225, and the ratio to the linear stiffness of the steel beam is 0.7, the seismic performance is close to or superior to that of traditional welded steel frame beam-column joints, that is, equal to or better than traditional welded steel frame beam-column joints.