Compressive Behaviour of Concrete Retrofitted with Fibre Reinforced Polymer Wrapping Subjected to Elevated Temperature

Abstract

Concrete structures often collapse in fire due to material degradation and thermal expansion. The compressive behaviour of concrete retrofitted with fiber-reinforced polymer (FRP) wrapping under elevated temperature conditions. The study addresses the critical issue of assessing the performance of structural elements, particularly concrete columns, when subjected to fire events. The composite material made of fibre-reinforced polymer (FRP) has recently gained attention as a potential repair method for damaged concrete structures. This study aimed at determining the influence of fire damage on concrete specimens retrofitted with Glass FRP, Aramid FRP, and Basalt FRP laminates by destructive and non-destructive methods. The cube specimens were subjected to temperatures of 250, 500, and 750°C for a period of 1, 2, and 3 hours followed by retrofitting with FRP laminates. The research emphasizes the importance of considering not only the mechanical properties but also the fire-resistant characteristics of retrofitting materials in optimizing the performance of concrete structures under extreme conditions.The results indicated an increase in compressive strength of concrete when subjected to 250ºC for 1 hour beyond which it decreased. However, a fall in compressive strength was observed for higher ranges of temperature and duration of the fire. Irrespective of the FRP wraps used, the compressive strength increased in comparison with the conventional concrete.