Abstract:This paper aims to study the effect of single-doped steel fiber, monofilament polypropylene fiber and cellulose fiber on compressive strength and flexural toughness of concrete. The compressive strength and flexural toughness of concrete specimens were firstly tested under different volume fraction of fibers, and the variability of test results was then analyzed. The test results show that the compressive strength of the three kinds fiber reinforced concrete are 26.7%, 6.1% and 11.1% higher than that of normal concrete respectively. The average retention tate of secondary compressive strength are 77.0%, 45.7% and 58.0%. The flexural toughness index I20, Nemkumar index PCSm, and toughness ratio Rx of fiber reinforced concrete are 4.2 times, 3.1 times, 2.6 times, and 19.9 times, 9.8 times, 6.9 times, and 4 times, 3.4 times, 2.7 times higher than of normal concrete respectively, which these based on load-deflection curves, Nemkumar method and bending-tension stress-strain curves, The results of the variability analysis show that the compressive strength of concrete is less than the flexural toughness after the incorporation of fiber. Meanwhile, the coefficient of variation of flexural toughness of concrete obtained from Nemkumar method and bending stress-strain curves is less than that of load-deflection curve method. Overall, the compressive strength and flexural toughness of steel fiber reinforced concrete are the most significant with the smallest coefficient of variation, and the compressive strength of cellulose fiber reinforced concrete and the flexural toughness of polypropylene fiber reinforced concrete are relatively significant.