Cyclic Behavior of Cold-Formed Steel Frames with Strap Bracing

In the present research, inelastic behavior of cold-formed steel frames with strap bracing was studied under cycling loading using finite element (FE) method. All of frame members including tracks, studs, and braces were modeled using two dimensional shell elements. The screw connections of braces to studs were simulated using connector elements. The shear and axial strength of screws were determined considering the screw pull-out and hard contact of braces to studs. The failure mechanism and resultant base shear were compared with the experimental measurements. The results showed a good agreement between developed FE model and experimental data. The shear and tensile forces of screws at different stages of loading, as well as the behavior in elastic and inelastic regions, were evaluated using the developed model. It was concluded that the buckling and yielding of braces are the most effective factors on the cyclic behavior of cold-formed steel frames; and that cyclic behavior of cold-formed steel frames with strap bracing can be accurately determined using the proposed FE model