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An experimental study was performed on the splitting tensile strength of steel fiber reinforced concrete using cube and cylinder specimens. Effects of volume fraction, aspect ratio, geometry, and tensile strength of steel fiber on the splitting tensile strength of steel fiber reinforced concrete with different water-to-binder ratio were investigated systematically. The test results showed that the splitting tensile strength of steel fiber reinforced concrete increases with volume fraction and aspect ratio of steel fiber. And it can be improved more obviously by hooked-end steel fiber compared with wave-shaped and corrugated steel fibers. Steel fibers with higher tensile strength (.600 MPa) are recommended for steel fiber reinforced concrete with compressive strength larger than 70 MPa. A factor used to convert cubic strength to cylindrical strength for steel fiber reinforced concrete was obtained, which is 0.738 for compressive strength and 0.96 for splitting tensile strength. In addition, a calculation method for predicting the splitting tensile strength of hooked-end steel fiber reinforced concrete including impact coefficient of steel fiber was developed based on the test results, which shows reasonable predictions for all test data.

This research investigated the flexural behavior of high-strength concrete beams reinforced with continuous basalt fiber-reinforced polymer (BFRP) bars and discrete steel fibers. Five concrete beams with the dimensions of 150 × 300 × 2100 mm3 were constructed and tested to failure under four-point bending cyclic loading. The specimens consisted of four BFRP-reinforced concrete beams with various reinforcement ratios (ρf), namely, 0.56%, 0.77%, 1.15%, and 1.65%, and one conventional steel-reinforced concrete beam for comparison purposes. The cracking behavior, failure modes, load-deflection behavior, residual deformation, and stiffness degradation of the beams were studied. Additionally, a deformation-based approach was used to analyze the deformability of the beams. The results show that an increase in the ρf effectively restrained the crack widths, deflections, and residual deformation while also enhancing the flexural bearing capacity of the beams. In comparison to the first displacement cycle, the bearing capacity dropped by 10% on average in the third cycle. The stiffness exhibited a fast to slow degradation trend until failure. The residual stiffnesses were higher in beams with a higher ρf. The over-reinforced beams had superior deformability than the under-reinforced beams, according to the deformability factors.

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