Mechanical properties of geopolymer concrete specimens exposed to fire retrofitted with glass and basalt fiber reinforced polymer laminates.

Exposure of concrete to elevated temperature affects its mechanical and physical properties. One of the important reasons for the use of fiber‐reinforced polymer (FRP) composite materials is because of its superior mechanical properties. These mechanical properties include impact resistance, strength, stiffness, flexibility, and also it is enhanced ability to carry loads. The high strength–weight ratio, and corrosion resistance of FRPs made them suitable for repair. For strengthening and retrofitting of concrete structures confinement with FRP has received considerable attention in recent years. Geopolymer concrete (GPC) can be expressed as “concrete without cement.” GPC is environmentally friendly and an inventive way to replace the conservative concrete which contributes 7%–8% of total CO2 production in the world. “The concrete which entails of the source materials and the alkaline solution.” The composite material made of fiber‐reinforced polymer (FRP) has recently gained attention as a potential repair method for concrete structures that have been damaged. This study investigates the performance of glass and basalt fiber‐reinforced polymer (GFRP and BFRP) laminates as a retrofit solution for fire‐damaged GPC specimens. The specimens were subjected to temperatures of 200°C, 400°C, 600°C, and 800°C for a period of 1, 2, and 3 h, followed by retrofitting with FRP laminates. The results indicated an increase in the ultimate load‐carrying capacity of GPC specimens when subjected to 200°C for 1 h, beyond which it decreased. However, a fall in ultimate load capacity was observed for higher ranges of temperature and duration of the fire. In this project, geopolymer specimens that had been damaged by fire are wrapped with GFRP and BFRP laminates to study the effect of confinement on the strength of GPC specimens. The fiber laminate used was bi‐directional glass and bi‐directional basalt. Based on the analysis of test data, there was the conclusion that the fire‐damaged GPC was strengthened when retrofitted with GFRP and BFRP laminates was attainable. [ABSTRACT FROM AUTHOR]