Analytical model for cyclic behavior of cold-formed steel bolted connection frames considering local buckling

Cold-formed steel (CFS) structures are increasingly popular in the construction industry due to their high strength-to-weight ratio, ease of fabrication, and cost-effectiveness. This study focuses on the development of a detailed mathematical model to accurately simulate the cyclic behavior of CFS moment-resisting bolted connection frames, particularly considering the local buckling of connected frames. Bolted joints are preferred in thin-walled CFS structures over welded joints due to their ease of installation and adaptability in seismic design, relying on slip and bearing mechanisms of bolts to accommodate inelastic deformations and dissipate energy during seismic events. The proposed model incorporates these mechanisms and validates them against experimental data and refined finite element analyses. Significant findings highlight the importance of the balanced number and arrangement of bolts in preventing excessive bolt slip and premature buckling. This research provides a robust analytical tool for optimizing bolted joint designs in CFS bolted connection frames, contributing to safer and more resilient CFS structures in seismic regions. The model's computational efficiency further enhances its practicality for engineers and researchers.