Flexural ductility of steel-polyvinyl alcohol fiber reinforced cement composite beam

Polyvinyl alcohol fiber reinforced cement (PVA/C) composites have superior tensile strain hardening characteristics, which can significantly improve the deformation capacity of the structure. Based on the PVA fiber volume fraction and the reinforcement ratio, the four-point bending experiment of six steel reinforced PVA/RC beams and two ordinary concrete (C) beams was carried out, and the ductility of the steel reinforced PVA/RC beams was analyzed. The experimental research shows that the area surrounded by the load-deflection curve of the steel reinforced PVA/C beams is 1.64-3.71 times of the RC beam, which proves that the steel reinforced PVA/RC beams have better holding deformation ability. When the PVA fiber volume fraction is constant, the curvature ductility coefficient of the test beam decreases with the increase of the reinforcement ratios. In the case of a certain reinforcement ratio, the curvature ductility coefficients of the steel reinforced PVA/C beams are 1.56-2.02 times that of the C beam, which proves that the incorporation of PVA fiber significantly improves the ductility of the test beam. The calculation formula of the curvature ductility coefficient of the steel reinforced PVA/C beams was established, and the influence of the PVA fiber volume fraction on the ductility coefficient and the height coefficient of pressurized zone was analyzed. The test results are in good agreement with the calculated results.