Effects of the strain rate and fiber blending ratio on the tensile behavior of hooked steel fiber and polyvinyl alcohol fiber hybrid reinforced cementitious composites

摘要

The strain rate effect on the tensile behavior of high performance hybrid fiber reinforced cementitious composites was evaluated according to the blending ratio of hooked steel fiber (HSF) and polyvinyl alcohol fiber (PVA). The tensile strength, strain capacity, peak toughness, and softening toughness were investigated. In the experimental result, specimen with 1.5 vol% HSF and 0.5 vol% PVA (HSF1.5PVA0.5) exhibited the highest tensile strength and softening toughness. However, the strain capacity and peak toughness were less than those of the specimen with 2.0 vol% HSF (HSF2.0). Nevertheless, HSF1.5PVA0.5 exhibited the highest dynamic increase factors (DIFs) for the tensile strength, strain capacity, and softening toughness. HSF2.0 showed a higher DIF for the peak toughness than HSF1.5PVA0.5. But HSF1.5PVA0.5 is expected to exhibit a higher DIF for the peak toughness than HSF2.0 at high strain rates (>10(1) s(-1)), because it have highest strain rate sensitivity of tensile strength and strain capacity.