Estimating Postfire Residual Capacity of Heavily Damaged Concrete Members

This paper presents a five-step approach to estimate residual capacity of concrete members that undergo severe temperature-induced damage during fire exposure. Limited information pertaining to the fire event, including fire timeline, peak fire temperature, and compartment characteristics, is utilized to estimate fire severity in the first step. In the second step, peak temperatures experienced on exposed surfaces of the structural members at different locations in the structure (compartments) are estimated through visual inspection. A more detailed classification of temperature-induced damage in structural members based on information collected through visual assessment is performed in the third step. Subsequently, residual capacity of the structural member is estimated in the fourth and fifth steps through either simplified or advanced analysis methods based on the extent of damage as per the classification scheme. The proposed approach can be applied in practice for postfire residual capacity assessment of severely damaged concrete structures.