Analytical model for predicting the load-deflection curve of post-fire reinforced-concrete slab

This paper firstly presents the experimental results of two simply supported full-scale reinforced-concrete (RC) slabs (unheated and fire-damaged). Thereafter, an analytical model for predicting the load-deflection curves of post-fire RC slabs is described in detail. The model can predict ultimate loads and displacements in both post-fire RC slabs and those at ambient temperature. The developed model has been validated using test data generated in this research and previous research and compared with a few analytical models developed by other researchers; some of the proposed model's advantages are highlighted in this paper. Results indicate that the model can be employed to determine the residual strength of post-fire RC slabs with reasonable accuracy. It is evident that steel strain differences and vertical shear forces in the slab have considerable effects on the load-carrying capacities of unheated and fire-damaged RC slabs.