Development and Validation of a Segment Fiber Model for Simulating Seismic Collapse in Steel-Reinforced Concrete Structures Using the Discrete Element Method

In this study to accurately simulate the entire collapse process of steel-reinforced concrete (SRC) building structures subjected to seismic actions, a segment fiber model of SRC components (SRC-SFM) was constructed based on the segment fiber model of the discrete element method (DEM) with the introduction of steel fiber bundles. The internal steel and reinforcement fiber bundles were modeled using a uniaxial steel constitutive model, while the concrete fiber bundles were represented by a uniaxial concrete constitutive model that considered the confinement provided by the steel and stirrups. Subsequently, the hysteretic performance of the SRC components and frames was simulated, and the results indicate that the model can effectively capture their hysteretic behavior. A dynamic elastoplastic analysis was conducted on an SRC structure model, and the results obtained from the discrete element software DEM-COLLAPSE were compared with those generated using the finite element software ABAQUS6.96.9. The results indicate that when the acceleration amplitude is relatively low, the computational results are highly consistent with those of the ABAQUS6.9-SRC structural model. At higher acceleration amplitudes, while some numerical differences are observed, the overall trend of the curves re-mains consistent. This demonstrates that the results of dynamic elastic-plastic analysis obtained from DEM-COLLAPSE are of significant reference value, which lays a solid foundation for the application of DEM-COLLAPSE in subsequent collapse simulations of SRC building structures.