Numerical analysis of RC frames under column removal: A review of current methods and development of a reduced-order approach

This study presents a comprehensive numerical investigation of reinforced concrete (RC) frames subjected to column removal, with a focus on structural robustness and resistance to progressive collapse. It reviews existing modeling approaches, evaluating the strengths and limitations of both explicit and implicit finite element analyses, as well as various strategies for modeling concrete and steel reinforcement. A novel reduced-order model (ROM) is proposed, which enhances simulation efficiency and accuracy by employing strategically refined meshes in regions of high stress concentration, outperforming conventional full-order models. Utilizing Abaqus, a series of comparative parametric studies was conducted to evaluate different reinforcement element types, mesh configurations, and overall model performance in terms of error and computational time. The results demonstrate that the proposed ROM provides higher efficiency and accuracy in the simulation of compressive and catenary structural behavior under extreme loading conditions. Furthermore, modeling steel reinforcement with truss elements, rather than beam elements, demonstrated superior computational efficiency, making them more suitable for large-scale progressive collapse simulations. These findings offer valuable insights for optimizing progressive collapse modeling and provide a practical framework for designing resilient RC structures in high-risk environments.