Effect of Fibre Reinforced Polymer Wrapping on Mechanical Properties of Concrete Subjected to Fire

Concrete buildings often fare rather well in a fire and can usually be restored after one has occurred. The concrete cover has a very low thermal conductivity, which, if it stays intact, keeps the interior reinforcing steel and the concrete at relatively low temperatures over extended periods of intense heat. This work reports on an extension of the application of fibrereinforced polymer confinement technology for reinforcing burned concrete columns. Following a four-hour heating cycle to gradually higher temperatures and a cooling period to room temperature, in order to investigate the compressive strength and stress-strain behaviour of plain concrete, both unconfined and FRP confined, an experimental program was started. The outcomes demonstrate how well FRP confinement works to increase even badly fire-damaged concrete columns' ability to support loads. The findings also shed light on the mechanics of FRP confinement of concretes with different compressive strengths but similar compositions.