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Abstract: This paper presents the influence of adding steel fibers and incorporation of silica fume on the mechanical properties of high-strength concrete. The variables investigated were steel fiber volume fraction (0 to 1.5%), silica fume replacement (5, 10 and 15%) and water-to-binder ratio (0.25, 0.30, 0.35 and 0.40). The influence of fiber content in terms of fiber reinforcing index on the compressive and splitting tensile strengths of high-strength steel fiber reinforce concrete (HSFRC) is presented. The use of silica fume increased both the compressive and splitting tensile strengths of concrete at 28 days. On the other hand, the addition of crimped steel fiber into high-strength concrete improves splitting tensile strength significantly. Based on the test data, using regression analysis, empirical expression to predict 28-day tensile strength of HSFRC in terms of fiber reinforcing index was developed and the absolute variation and integral absolute error (IAE) obtained was 3.1% and 3.3, respectively. The relationship between splitting tensile and compressive strength of SFRC was reported with regression coefficient (r) = 0.9. The experimental values of previous researchers were compared with the values predicted by the model and found to predict the values quite accurately.