Performance of Recycled Aggregate Concrete Containing Hooked-End Steel Fibers at Elevated Temperatures

The present study investigates the performance of recycled aggregate concrete (RAC) reinforced with hooked-end steel fibers at elevated temperatures. The amount of recycled concrete aggregate (RCA) is taken as 50% of the total coarse aggregate content and the steel fibers are added by 1% of total concrete’s volume. For comparison purpose, a controlled mix containing 100% natural aggregates and 1% steel fibers is made. The mechanical properties, that is, compressive strength and split-tensile strength of each concrete mix are examined after subjecting the concrete specimens to ambient as well as elevated temperatures. A relationship is developed between the split-tensile strength and compressive strength. The microstructure of specimens exposed to different temperatures is investigated using scanning electron microscopic (SEM) technique. It is found that both mechanical and microstructural properties of each concrete mix deteriorate with the rise in temperature.