Authors: Shih-Ho Chao (The University of Texas at Arlington) , Bhupendra Bhupendra Acharya (The University of Texas at Arlington) , Sujan Singh (The University of Texas at Arlington)
This paper presents experimental studies conducted on the tensile properties of ultra-high-performance fiber-reinforced concrete (UHP-FRC) reinforced with high-strength steel hooked fibers with a fiber volume fraction of 1.5%, 2%, 2.25%, and 2.4%. A comparison is made between its behavior and that of UHP-FRC reinforced with commonly used high-strength straight smooth steel fibers. The experimental results indicate that UHP-FRCs reinforced with steel hooked fibers exhibited greater tensile strength (except for the 1.5% fiber volume fraction) and ductility than UHP-FRCs reinforced with straight smooth steel fibers. Additionally, the use of hooked fibers enables the production of UHP-FRC by pre-placing the fibers in the mold, followed by slurry infiltration with UHPC materials. This method results in the production of ultra-high-performance slurry infiltrated fiber-reinforced concrete (UHP-SIFCON) that enables the incorporation of a high fiber dosage. This, in turn, leads to the highest possible mechanical properties, such as strength and ductility, in UHP-FRCs. Based on the experimental results, it was found that the UHP-SIFCON produced (with a steel hooked fiber volume fraction of 7.5%) exhibited exceptional toughness. Specifically, it maintained a high compressive strength of over 33 ksi (228 MPa) up to a compressive strain of approximately 9% and a tensile strength of around 2.4 ksi (17 MPa) until a tensile strain of about 1.2%. UHP-SIFCON exhibits a considerably better tensile performance compared to conventional UHP-FRCs with 3% straight smooth steel fibers, which generally maintain a peak tensile strength of 1.1 ksi (7.6 MPa) up to approximately 0.3% tensile strain.
Keywords: UHP-FRC, Direct Tensile Test, Strain-Hardening, Hooked Fiber, SIFCON
How to Cite: Chao, S. , Bhupendra Acharya, B. & Singh, S. (2023) “Tensile Properties of UHP-FRC Reinforced with High-Strength Steel Hooked Fibers and Ultra-High-Performance Slurry Infiltrated Fiber-Reinforced Concrete (UHP-SIFCON)”, International Interactive Symposium on Ultra-High Performance Concrete. 3(1). doi: https://doi.org/10.21838/uhpc.16713