Fire resistance of RC beams under design fire exposure

This paper presents the development of a design approach for predicting the fire resistance of reinforced concrete (RC) beams exposed to design fire. The proposed method is based on the energy-based time equivalence method in combination with a correction factor that is formulated as a function of concrete cover depth and compartmental characteristics. In the proposed approach, the fire resistance period of an RC beam under design fire exposure can be deduced from that of the same RC beam under standard fire exposure; the latter can be predicted using a set of explicit equations previously developed by the authors. The fire resistance data of RC beams under design fire exposure, which were used to formulate and validate the proposed approach, were generated using a reliable finite-element approach. The proposed design approach is shown to be accurate in predicting the fire resistance of RC beams under design fire exposure.