Journal of Science and Geosciences

Imperviousness of fire towards strengthening cement unbending shafts

Abstract


Muamma Omar Sharif

The effect of burning by fire flame on the behavior and load carrying capacity of rectangular reinforced concrete (RC) rigid beams is addressed in this paper. Reduced scale beam models (which are believed to resemble as much as possible field conditions) were suggested. Five end restrained beam specimens of casting and testing. The specimens were subjected to fire flame temperatures ranging from (25-750°C) at age of 60 days, two temperature levels of 400 and 750°C were chosen with exposure duration of 1.5 h. The rectangular reinforced concrete beam (2250×375×375 mm) (length× width× height respectively) were cast and subjected to fire. Test results indicate remarkable reduction in the ultrasonic pulse velocity and rebound number of the rigid beams cooled in water were (2-5%) more than the rigid beam specimens cooled in air. Load-deflection curves indicate deleterious response to the fire exposure. Also, it was noticed that the maximum crack width increases with increasing fire temperature.

PDF

Share this article

Get the App