Steel fiber

To cut off the thin wire method, cold-rolled strip steel cut, steel ingot milling or rapid condensation method aspect ratio (ratio of fiber length to its diameter, when the fiber is non-circular cross-section, the use of conversion sectional area of ??a circle equivalent diameter) 40 to 80 fibers. To cut off the thin wire method, cold-rolled strip steel cut, steel ingot milling or rapid condensation method aspect ratio (ratio of fiber length to its diameter, when the fiber is non-circular cross-section, the use of conversion sectional area of ??a circle equivalent diameter) from 30 to 100 fibers. Use of steel fibers are mainly used in the manufacture of steel fiber reinforced concrete, any method of production of steel fiber can play a role in strengthening the concrete. Enhancement depends on the fiber matrix strength (fm), fiber aspect ratio (steel fiber length l and diameter d ratio, that I / d), the volume of the fibers (steel fibers in the fiber volume percentage of steel in concrete ), the bond strength between the fiber and matrix (τ), and fiber distribution in the matrix and orientation (η) impact. When the steel fiber reinforced concrete damage, mostly fibers are pulled out and not pulled off, thus improving the bond strength between the fiber and the matrix is ??one of the main controlling factor in improving fiber reinforced effect. Steel fiber concrete compressive strength, tensile strength, flexural strength, impact strength, toughness, impact toughness properties are improved greatly. Combination of steel fiber concrete tensile strength, flexural strength (tensile strength) design formula tensile strength of steel fiber concrete tensile strength of steel fiber reinforced concrete, can be multiplied by splitting tensile strength tests were performed to determine the reduction factor 0.80, splitting tensile strength test methods according to GB J81 provisions of the tensile strength of steel fiber reinforced concrete standard value fftk = ftk (1 + αt? ρf? lf / df) fftk, ftk-- the tensile strength of steel fiber reinforced concrete standard value, design value ; αt-- steel fiber tensile strength of steel fiber reinforced concrete impact factor, should be determined through experiments; ρf-- fiber volume fraction (ie, the volume ratio of steel fiber content) lf-- steel fiber steel fiber diameter or length df-- equivalent diameter lf / df-- steel fiber aspect ratio