Fire effect on the tensile resistance of slabs steel reinforcement

This paper resume the results of the evaluation of the slabs steel reinforcement performance under the fire action, with the variation of the bar recoverment, studying the positive reinforcement steel tensile resistance. 9 slabs models were elaborated with 50cm x 70cm x 20cm dimensions, with 1, 3 y 5 centimeters of concrete recoverment; additionally 6 steel bars were tested, 3 of them were directly exposed to fire, and the rest were non fire exposed and were used like a model reference to compare the obtained tensile resistance. Every slabs were exposed to fire for 60 minutes, heated over a 400 degrees C temperature, after that the steel bars were extracted and tested. The results showed an excellent performance of the concrete like an isolating material, because all of the tested bars showed a similar stress-deformation diagram.