Thermal stress–strain analysis of CFRP-laminated concrete beam with partial replacement of fine aggregate by PET granules

In the present research, the effect of temperature on this beam had been examined by substituting sand partially with polyethylene terephthalate (PET) granules up to 50% and laminating with Carbon Fiber Reinforced Polymer (CFRP) sheet externally by ABAQUS. The thermal stress–strain analysis had been done under a concentrated load in the present research by considering three cases. The first case was applying elevated temperature applied at the bottom face and ambient temperature was applied at the rest of the faces, whereas the second case was applying ambient temperature at both cross section and the top side of the beam and elevated temperature to the rest of the faces. And for the third case, the ambient temperature was applied to both cross section and bottom of the beam and the elevated temperature was applied to the top as well as both longitudinal side surfaces of the beam. It was found that the internal stress generated for the third case was maximum as compared to the second and the first case because in the third case, the most part of the compression zone of the beam was exposed to an elevated temperature that causes easy spalling of concrete. The various structural behaviors such as load deflection, flexural strength and cracking pattern had been analyzed briefly at worst condition. It was concluded that the PET-based concrete beam could be used at elevated temperature in which the sand could be replaced up to 20% by PET granules laminated with CFRP sheet on its surroundings.