This paper develops a generalized component-based model (CBM) for extended endplate (EP) joints designed to be applicable in progressive collapse scenarios induced by fire, which is capable of capturing the nonlinear full-range behavior of EP joints from initial yielding to ultimate failure. Based on refined FE modeling established in preceding studies, a simplified CBM method is established to simulate the collapse resistance of EP joints subjected to fire-induced column removal scenarios. For panel zones of fire-exposed EP joints, a trilinear model is applied to characterize the three-phase force-deformation behaviors of “linear-hardening-unloading” for axial springs, while a relatively large shear stiffness is used to characterize the minor shear deformation at the panel zones. For connecting zones of fire-exposed EP joints, the respective constitutive models and corresponding spring parameters for diverse spring components are established based on the strain distributions and loading transmission mechanisms of equivalent T-stub components. The proposed simplified CBMs with detailed spring parameters as well as their constitutive laws were incorporated into the ABAQUS program to validate against both experimental results and refined FE modeling. A comparative study with test data manifests that the proposed CBM method can precisely capture the collapse response of EP joints at elevated temperatures with high computing efficiency.
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