CFD simulation-based fragility analysis of reinforced concrete buildings damaged by traveling fire

This study aimed to develop a computational fluid dynamics (CFD) model of a reinforced concrete building exposed to traveling fires to assess its thermal behavior. Hence, a CFD-based framework was constructed to identify the vulnerability of damaged members within a building subjected to traveling fires. A fragility curve for a member was developed through the convolution of demand and capacity models. The demand was established using pairs of structural responses (maximum temperature of steel rebar experiences) and loading intensity measures (fire intensity). The capacity model was defined by the threshold of the maximum temperature of the rebar. To obtain sufficient response data for the fragility analysis, we used the CFD model to simulate various traveling fire scenarios, considering different combinations of fire intensity, ventilation coefficients, and traveling fire patterns. The results revealed varying structural stabilities and thermal behavior levels for each member under different fire scenarios. Subsequently, the most vulnerable members in reinforced concrete buildings were identified to facilitate retrofitting and repair.