High strength concrete has higher strength but lower ductility. Inclusion of single type of fibers into concrete has been proven to improve the behavior of concrete to a limited extent. However, recently it was found that the behavior of concrete can be improved more with the addition of hybrid fiber i.e., a combination of different types of fiber. This paper presents the results of an experimental investigation on the behavior of Hybrid Steel Fibre Reinforced High Strength Concrete (HSFR-HSC). A total of eight cylinder specimens with 150 mm in diameter and 300 mm in height were cast and tested under uniaxial compression. Three different combinations of HSFR-HSC specimens and reference specimens without steel fibers were prepared. The first combination of HSFR-HSC included 1.5% Micro Steel (MS) fibers and 1% Deformed Steel (DS) fibers. The second combination included 1.5% MS fibers and 1.5% Hooked-end Steel (HS) fibers. The third combination included 1% DS fibers and 1.5% HS fibers. The experimental results showed that the addition of hybrid steel fibers improved the strength and ductility of high strength concrete compared to the reference specimens. The results also showed that the specimens reinforced with different hybrid steel fibers failed in a ductile manner, while the reference specimens failed in a brittle manner.
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