Composite reinforcement strength at high temperatures: The influence of preheating

The object of research is the composite reinforcement at high temperatures. Method. During the study, 16 specimens with composite rods bonded with epoxy resin on metal tubes were prepared. The specimens were tested using a universal hydraulic machine and pre-heated using a heat gun to heat the reinforcement to various temperatures (20°C, 100 °C, 150 °C, 250 °C, and 300°C). The maximum breaking load was determined for specimens with and without preheating. Results. Test results show that preheating the rods increases the strength of composite rods at elevated temperatures. As the reheating temperature increases, the effect of preheating on the strength of the composite rebar increases. The difference in maximum tensile strength between preheated and unheated rods, tested at 300 °C, reaches 50%.