Influence of fiber type on mechanical properties of lightweight cement-based composites

Abstract

This article discusses the influence of fiber types, including polyvinyl alcohol (PVA) fiber, polyethylene (PE) fiber, and steel fiber (SF), on the compressive strength, flexural strength, bending toughness, and tensile ductility of lightweight cement-based composites. The fiber dispersion and the microscopic morphology were assessed using fluorescence and scanning electron microscopes. The result showed that the SFs had the best effect in enhancing the compressive and flexural strengths of lightweight cement-based composites, and its compressive and flexural strengths reached 88.9 and 17.6 MPa, respectively. Compared with the PVA and the SFs, the PE fiber had the most significant effect on the ductility of lightweight cement-based composites; the tensile strength and the ultimate tensile strain were 3.29 MPa and 2.56%, respectively, due to a very high bridging capability provided by the PE fiber. A large amount of hydration products adhered to the surface of the PVA fiber, which improved the adhesion between the cement matrix and the PVA fiber and caused the rupture of most of the PVA fiber. Overall, lightweight toughness cement-based composites containing PVA and PE fibers have a good deformability, which can meet the needs of construction and transportation engineering applications.