The seismic performance of K-braced cold-formed steel shear panels with improved connections

In this paper the performance of light weight K-braced cold formed steel (CFS) shear panels under cyclic loading is experimentally evaluated. It is generally known that the brace-stud connection details has an important effect on the performance of the braced CFS shear panels in terms of lateral stiffness, energy dissipation, and ductility factor. In this study, four full-scale, 2.4 m x 2.4 m, braced CFS shear panels made of C-sections were tested. It was observed that proper modification of the currently utilized braced to stud connections in K-braced, CFS shear panels could enhance their performance considerably by increasing their ultimate shear resistance up to 7 folds. Furthermore, using gusset plate in the braced to stud connection of the K-braced CFS shear panels were shown to significantly increase their shear strength, energy dissipation and ductility capacities in comparison to the CFS shear panels with regular connections. That is due to the shifting of the failure modes which commonly occurs at the brace-stud connections, to buckling of the brace elements. As the obtained results indicate, the proposed connection modifications could appreciably improve the performance of these panels in comparison to those that are built based on current practice, without any appreciable increase in cost or installation effort.