Open Access Open Access  Restricted Access Subscription or Fee Access

Strain Rate Effects on Tensile Behavior of Ultra High Performance Hybrid Fiber Reinforced Concrete

Tran Tuan Kiet, Kim Dong Joo


Strain rate effect on direct tensile behavior of ultra-high-performance hybrid-fiberreinforced concrete (UHPHFRC) containing two types of macro fiber, steel (S-) and polyamide (P-), and one type of micro fiber, polyamide (p-), at high strain rates (10 and 47 s-1) was investigated. The volume content of macro fiber was maintained as 1.0%, whereas that of micro fiber varied from 0.0 to 1.5%. The UHPHFRCs with steel macro fibers (S-UHPHFRC) produced much higher rate sensitive tensile behavior than those with polyamide macro fibers (P-UHPHFRC). As the volume content of micro polyamide fibers increased, P-UHPHFRC produced higher rate sensitivity on post cracking tensile strength whereas S-UHPHFRC showed lower sensitivity. A proper amount of micro polyamide fibers, 0.5% in this study, would noticeably improve the impact resistance of S-UHPHFRCs, especially for strain capacity and peak toughness.

Full Text: