Abstract: The influence of "hybrid effect" caused by the basalt fiber and polypropylene fiber on the mechanical properties of the concrete of matrix is discussed. The results show that the splitting tensile strength and flexural strength of basalt-polypropylene hybrid fiber reinforced concrete (B-P HFRC) is obviously higher than those of basalt fiber reinforced concrete (BFRC) and polypropylene fiber reinforced concrete (PFRC). Meanwhile, the concept of "fiber hybrid effect function" was proposed. The hybrid effect function of basalt-polypropylene hybrid fibers is obtained by the method of MATLAB data fitting. By confounding the "the hybrid effect function of basalt-polypropylene hybrid fibers" extremum the optimum basalt-polypropylene hybrid fibers volume mixing ratio, which improves the mechanical properties of concrete, was obtained.

Key words: basalt fiber, polypropylene fiber, hybrid fiber reinforced concrete, hybrid effect function