Fire scenario-based damage assessment of ductile reinforced concrete buildings using computational fluid dynamics models

This study aims to develop a computational fluid dynamics (CFD)-based framework to assess the thermal behavior of reinforced concrete (RC) structures with non-uniformly distributed fire damage. To achieve this, a CFD model that can predict fire-induced temperature was validated using experimental data of an RC column specimen obtained from an existing study. It was then extended to develop the CFD model of an RC building frame to investigate the extent and pattern of damage to its columns and beams under various fire scenarios, combinations of fire intensity, ventilation coefficient, and fire source locations. The non-uniform temperature distributions of the columns and beams were used to modify the stress-strain curve of concrete and rebar and to perform a moment-curvature analysis to evaluate their residual flexural strength. The computed flexural strengths were compared with those obtained from existing design guidelines. The guidelines were determined to be extremely cautious compared to the results of the proposed method.