Abstract
The bending properties of synthetic fiber reinforced concrete were evaluated from the standpoints of bending strength and bending toughness coefficient based on the results of bending tests. In addition, bond properties between fibers and matrix were evaluated with regards bond strength and bond toughness coefficient as results of fiber bond tests. Polyvinyl alcohol (PVA) fiber had strong chemical bonds with matrices, resulting in high bending strength of fiber reinforced concrete. The chemical bond, however, was lost in large deflection zone during load applying stage, and the pullout load reduced greatly. Consequently, both the bond toughness coefficient of fibers and bending toughness coefficient of fiber reinforced concrete were also decreased. Though the bond strength of polyethylene & polypropylene monofilament (PE&PP) fiber was lower compared to PVA fiber, PE&PP fiber showed higher bond toughness coefficient. It was reasoned that the surface area per unit volume of PE&PP fiber was actually larger. As a result, the bending toughness coefficient of PE&PP fiber reinforced concrete was also higher. It was clearly shown that the bond properties of fibers strongly influence on the bend properties of fiber reinforced concrete.
