Effect of Sustained Elevated temperature on Mechanical Behavior of Reinforcing Bar

摘要

The mechanical properties of reinforcing steel deteriorates when exposed to fire. Many structures like nuclear reactor, chimneys experiences sustained elevated temperature, hence a study has been carried out to understand the effect of sustained elevated temperature on reinforcing bars. In the study 20 mm diameter bars were heated at temperatures 200, 300, 400, 500, 600 and 700° C and were sustained for 0.5,1 and 2 hours. The bars were cooled naturally in air to ambient temperature and were tested in tension. The yield strength, tensile strength and percentage elongation were observed. The observations showed that yield strength and elongation was changed significantly while the ultimate strength remained unchanged with increase in duration of exposure for the same temperature.