Cyclic behaviour of as-built and strengthened existing reinforced concrete columns previously damaged by fire

A structure, during its life, may be subjected to multiple hazards. These hazards are sometimes combined over a short period of time, or in some cases occur many years apart, with the first hazard influencing structural response under second hazard. reinforced concrete (RC) structure previously damaged by fire and then exposed seismic loading is one such example. To assess structures, effects on cyclic performance RC elements needs better understood. Moreover, it also important develop validate strengthening methods that can reinstate improve fire-damaged elements. This paper presents results novel experimental campaign where six full-scale columns detailing representing existing Mediterranean buildings designed old codes loading. Four were after exposure 30 90 min ISO 834 standard curve furnace tested uniaxial lateral up failure. Two these repaired strengthened post-fire Carbon Fibre Reinforced Polymer (CFRP) wrapping. The method aimed increase strength through confinement, displacement ductility energy dissipation capacity additional control columns, as-built another strengthened, cyclically for comparison columns. It was found resulted few cracks, whilst cover spalling general cracking observed exposure. significant decrease dissipated following exposure, even fire. had repair CFRP strengthening, showed than column without reach similar similarly previous damage.