The behavior of glued steel fibres in high strength concrete with size reduction properties of concrete has been attempted. Glued steel fibres with both ends hooked having length to diameter ratio of 70 was added at a dosage level of 0.5% to 1.5% by volume fraction. The study was carried out to analyze the effects of fibre addition on the thickness reduction of concrete element. A high strength concrete mixture was designed and various thicknesses of concrete prisms were casted for different volume fraction of steel fibres. The hardened concrete properties were determined based on the mix constituents such as water to binder ratio 0.3 (w/b), superplasticizer dosage, fine to coarse aggregate ratio 0.6 (F/c), and fly ash replacement level at 25% and 50% by weight of binder content. The experimental test results showed that the flexural strength varies with respect to the depth of concrete specimen. It can be observed that the reduction in size up to 10% size containing 25% fly ash with 1.5% steel fibres showed better strength enhancement of 4.70？MPa and 6.69？MPa for 7 days and 28 days, respectively. Also, the addition of steel fibres at higher percentage of fly ash containing 50% showed better improvement in the flexural strength for the size reduction at 5%, when compared to plain concrete beam which exhibited higher stress carrying capacity of 6.08？MPa at 28 days and showed an increase of 7.99%. 1. Introduction Fibre addition in plain concrete are known to improve the brittle failure properties of concrete as it controls the crack propagation in the matrix. However, the careful selection of the type of fibres can be potentially used to improve the toughness of concrete. The dispersion of fibres randomly in the concrete can promulgate the homogeneous properties in all directions. The major role of fibres being incorporated in plain concrete is to develop adequate tensile strength for effective crack bridging upon loading. It can be observed that the addition of fibres in concrete shows higher degree of ductile failure leading to high crack width reduction. The plastic deformation occurring in the postcrack region is an added advantage which is primarily borne by the discrete reinforcing mechanisms. The typical application of fibres is noted in the case of high strength concrete due to high brittleness fibres having more significant benefits in terms of improving flexural strength, elastic modulus, and long term durability. High strength concrete exhibits more brittleness under compression and addition of steel fibres in concrete improves the confinement,
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