Behaviour of polypropylene fibre-reinforced concrete beam with CFRP reinforcement under elevated temperature

In this paper the behaviour of concrete beam reinforced with carbon fibre-reinforced polymer (CFRP) bars under elevated temperature was numerically studied. The numerical modelling of the concrete beam (N-BECS20-2) reinforced with CFRP rebars was based on the experimental model (BECS20-2) studied earlier. The beams were modelled accounting for thermal gradients and material non-linearity using ABAQUS. To understand the effect of polypropylene fibre-reinforced concrete (PPFRC) under fire loads a new PPFRC beam with CFRP rebar reinforcement (NPP-BECS20-2) was numerically modelled and was compared with the behaviour of beam made of conventional concrete with CFRP reinforcement (N-BECS20-2). From the results the load carrying capacity and ductile behaviour of the PPFRC beam with CFRP bar reinforcement under elevated temperature were comparatively studied. The load carrying capacity and the ductile capacity of PPFRC beam (NPP-BECS20-2) under elevated temperature were found to be higher than the conventional concrete beam (N-BECS20-2). Parametric studies were carried out by varying the diameter of CFRP rebar and concrete cover at elevated temperature. The increase of cover of concrete to few millimeters protected the reinforcement from heat exposure resulting in better performance of PPFRC beam. © 2020, Springer Nature Switzerland AG.