Tensile Behavior of Normal-Strength Steel-Fiber Green Ultra-High-Performance Fiber-Reinforced Concrete

This paper investigates the tensile behavior of green ultra-high-performance fiber-reinforced concrete (UHPFRC) using commercially available steel fibers. An ecofriendly ultra-high performance concrete (UHPC) with a low carbon footprint was developed, aiming for a compressive strength of 150 MPa (22 ksi) and a high packing density (0.81) while using recycled glass powder and micro-limestone powder as partial substitution of silica fume and otdinaty portland cement. Besides the commercially available normal-strength deformed steel fibers, high-strength smooth steel fibers were used to establish a comparison. The study showed that, with appropriate hooked normal-strength and smooth high-strength steel fibers, 1% of fiber is enough to achieve strain hardening behavior. Moreover, the smooth fibers achieved the maximum tensile strength (sigma(pc) = 11.04 MPa) when 2% of volume was used. However, despite having less tensile strength, only the hooked-end fibers achieved a maximum post-cracking strain (epsilon(pe)) of over 0.3% using 2% of volume.