Recently, fiber reinforced polymers (FRP) have been widely used in repairing and strengthening of reinforced concrete (RC) structures. In order to increase the acceptance and application of FRP for strengthening requirements, their performance of in case of fire needs more investigation research works. Experimental investigations are required to be carried out for such elements to predict the fire behavior of such insulated FRP-strengthened members and their efficiency under realistic fire loads, however these experimental studies require time and cost.
The present paper gives numerical nonlinear finite element modeling of RC beams strengthened with FRP and insulated by a thermal resisting coating under elevated temperature specified by standard fire tests. The model take into consideration the variation in thermal and mechanical parameters of the concrete, steel rebar, FRP and insulation material. The nonlinear finite element analysis is performed using ANSYS 12.1. Finite element modeling of insulated RC T-beam strengthened with FRP which has been experimentally tested in the published literature is presented herein. The obtained analytical results are in good agreement with the experimental ones regarding the temperature distribution and mid-span deflection. The presented modeling gives an economical and efficient tool to investigate the performance of fire insulation layers under high temperatures. The model can be used to design thermal protection layers for FRP strengthening systems that satisfy fire resistance requirements specified in building codes and standards.