The effect of carbon nanotubes on the headed stud shear connectors for composite steel-concrete beams under elevated temperatures

This paper presents a novel experimental and numerical analysis of composite steel-concrete beams at elevated temperatures utilising carbon nanotube. Push tests were conducted as a part of the experimental study to determine the strength of the headed stud shear connectors in both normal concrete and carbon nanotube concrete. The specimens were tested under ambient temperature, 200°C, 400°C, and 600°C, respectively. Results from the experimental study illustrated the reduction of ultimate load and stiffness as temperatures increased. The numerical analysis was in good agreement with the experimental study results. Even though carbon nanotube had no effect on the ultimate load, however, the carbon nanotube reduced concrete spalling and cracking when compared to normal concrete. The carbon nanotube was observed to take effect at temperatures greater than 400°C. As a conclusion, the carbon nanotube concrete material would be an effective choice for reducing concrete spalling and cracking when exposed to elevated temperatures.