| Demolishing and rebuilding structures that have deteriorated, primarily from corrosion and heavy use, is not an economically viable alternative in most countries where infrastructure is in urgent need of rehabilitation. In recent years, fibre reinforced polymers (FRPs) have been extensively explored as materials to prolong the lives of civil engineering structures and to reduce maintenance costs. Today, FRP materials are being widely used in the repairing and retrofitting deteriorated bridges, however, their use in buildings have been limited, partly because of insufficient knowledge about the performance of FRP materials in fire. To enable further applications of FRPs in buildings, this thesis presents results from an ongoing study of the behaviour of reinforced concrete T-beams strengthened with externally bonded FRP sheets in fire. Also, presented are the studies of post-fire performance of these types of members.;Intermediate-scale reinforced concrete slabs and full-scale reinforced concrete T-beams were constructed, strengthened with FRP sheets, and insulated for fire protection. The results of two intermediate-scale fire endurance tests on FRP-strengthened slabs, two full-scale fire endurance tests on T-beams and four full-scale post-fire residual strength tests on T-beams, which were strengthened with FRP sheets prior to their fire tests, are presented and discussed. Based on these tests, reinforced concrete beams that are strengthened with FRP systems and protected with supplemental fire insulation systems, as described herein, are capable of achieving fire resistance ratings of more than four hours and retaining all of their pre-fire capacity after exposure to a standard fire. |
