Early‐age behavior of fiber‐reinforced self‐compacting concrete in high strain rate

Abstract This research investigates the early‐age behavior of fiber‐reinforced self‐compacting concrete under high strain rates and static loading conditions. Concrete made with steel fibers with volume fractions of 0%, 0.5%, and 1% is tested at three strain rates at different ages (28, 14, 7, 3, and 1 day) using a split‐Hopkinson pressure bar test setup. In all three strain rates, fibers did not influence the strength up to 3 days of age. At higher ages, the strength significantly improved at all strain rates. The modulus of elasticity was decreased with the increase in fiber dosage at all ages. However, increasing fiber dosage increases energy absorption at all ages due to crack arresting and improved ductility. The energy absorption increased marginally for specimens with 0.5% and 1% dosage. Test results of elastic modulus, energy absorption, and strain rate sensitivity at different ages show that the impact application requires a minimum steel fiber volume fraction of 0.5%.