Post-fire performance of slag-based geopolymer concrete exterior beam–column joint

Abstract

The post-fire performance of slag-based geopolymer materials in structures under cyclic loading has yet to be reported and the condition of the rebars inside such structures remains unexplored. In the present work, cyclic tests were conducted on exterior beam–column joints made with a slag-based geopolymer after exposing the specimens to natural fire. The mechanical properties of the reinforcement embedded in fire-exposed specimens were also determined and analysed. The cyclic test results indicated that deterioration of the geopolymer and rebar altered the failure pattern of the fire-exposed specimen from the desired beam-end hinging to joint shear failure. The peak load, stiffness, ductility and energy dissipation reduced significantly in the fire-exposed specimens compared with the unheated control specimens.