Numerical investigation of lateral impact performance of steel tube-reinforced concrete (ST-RC) column under fire

Incidents including damage, failure, and collapse of building structures frequently occur under the combined influence of multiple disasters such as fires and impacts. Research on ensuring the structural integrity of buildings throughout their service life, particularly for newly constructed structures, is currently inadequate. To elucidate the mechanical behavior of steel tube-reinforced concrete (ST-RC) columns under the combined effects of fire and lateral impacts, a comprehensive finite element model was developed. This model integrates static heat transfer and dynamic explicit analyses using the finite element software ABAQUS. The model's accuracy was corroborated with existing experimental data. Employing this model, a detailed analysis was conducted on the failure modes, energy variations, internal force redistribution, stresses, strains, and the time history curves of impact force and mid-span displacement of ST-RC columns under combined fire and impact conditions. Furthermore, a parametric study was performed to investigate the factors influencing the lateral impact resilience of ST-RC columns in fire scenarios. This research provides valuable insights for the design of fire and impact-resistant structures and offers a mechanical analysis foundation for the maintenance of similar structures in the face of such disasters.