Mechanical behavior of steel fiber-reinforced self-compacting concrete corbels after exposure to elevated temperatures

The paper presents an experimental study to investigate the effect of steel fiber (SF) on the mechanical behavior of self-compacting concrete corbels after exposure to elevated temperatures. This research examines the most relevant parameters that influence the behavior of reinforced concrete corbels (RC-corbels). These parameters comprise of the grade of concrete (medium [C50] and high strength concrete [C80]), the shear span-to-depth ratio (0.6 and 0.8), and the reinforcement ratio (0.82 and 1.6%). RC-corbels were prepared from self-compacting concrete with a constant percentage of polypropylene fiber of 0.1% and three different SF volume fractions of 0, 0.5, and 1.0%. All RC-corbels were tested before and after exposure to elevated temperatures (250, 500 and 750 degrees C). The results were presented in terms of load-deflection curves, crack patterns and failure modes. Results showed that the SFs have a positive effect on load-carrying capacity and ductility of RC-corbels both before and after exposure to elevated temperatures.