Research On The Hysteretic Behavior Of Cold-Formed Thin-Wall C-section Steel Members Under Constant Compression And Cyclic Bending

All kinds of economical cross-section configurations of the cold-formed thin-wall steel (CFS) members can be produced by cold-forming operations, and consequently favorable section shape can be obtained. Besides, CFS members can be prone to process, transport, install and industrialize. At present, CFS members have been widely utilized as principle structural members in low-rise light-gauge steel framed residences. However, research on CFS members is mainly focused on the range of elastic and static performance, and the hysteretic behavior of CFS members has not been researched deep. To explore the feasibility of light-gauge steel framed residences in seismic fortified areas, the researches for the hysteretic behavior of CFS members has great technical and economic significance.Based on the research results of domestic and overseas, the hysteretic behavior of CFS members under constant compression and cyclic bending is numerically simulated by finite element method. Through the finite element nonlinear analysis program ABAQUS, this paper uses S9R5 thin shell element and the linear kinematic hardening model for simulating geometric and material nonlinearities and Bauschinger effect, strain hardening and intensity increase at corner zone to establish the finite element models of CFS members under constant compression and cyclic bending, and utilizes existing theory and experiment results to verify the validity of the finite element models.To study the hysteretic behavior of CFS members under constant compression and cyclic bending, this paper establish the finite element models of cold-formed thin-wall C-section steel members under constant compression and cyclic bending, analyses the effect of the width-to-thickness ratio and the axial compressive ratio on the hysteretic behavior of the cold-formed steel members. Analytic results indicated that the width-thickness ratio and the axial compressive ratio affect the hysteretic behavior of the member evidently, as the increase of the width-thickness ratio, the resistance, rotation capacity and plastic deformation capacity decreases; then this paper research the final failure modes of this kind of member under the cyclic loading; by introduce the ductility coefficient to assess the aseismatic behavior of Cold-Formed C steel members, and some rational design suggestion are drawn initially.Since the width-to-thickness ratio of common C-section CFS members is large, so the hysteretic behavior of this member is bad. To solve the weakness of this member, this paper compare the hysteretic behavior between the C-section and intermediate stiffeners C-section member which has the same width-to-thickness ratio. The compare result show that setting intermediate stiffeners is a effective method to improve the hysteretic behavior of CFS member. Then the hysteretic behavior, deformed shape and the final failure modes of this...