A semi‐empirical tri‐linear model for progressive collapse resistance of self‐centering frictional frames

Abstract Self‐centering frictional frames (SCFFs) offer seismic resilience; however, their robustness against progressive collapse, a critical requirement for multi‐hazard design, remains poorly understood. Current assessment methods rely heavily on time‐consuming finite element simulations, lacking simplified analytical tools suitable for routine engineering practice. To bridge this gap, this study proposes a mechanics‐based semi‐empirical tri‐linear model to predict the progressive collapse resistance of SCFFs under a middle‐column loss scenario. The study identifies a unique hybrid mechanism combining flexural action (FA) governed by friction devices and catenary action (CA) from continuous reinforcement. Analytical expressions for yield, peak‐FA, and ultimate‐CA capacities are derived using static equilibrium and a numerical database, while displacement limits are formulated via sensitivity analysis. Validation against high‐fidelity simulations demonstrates an average prediction error below 6%. A resistance reduction factor of 0.88 is recommended for design safety. This research offers a concise, robust tool for quantifying SCFF collapse resistance.