Tensile behavior of Ultra High Performance Hybrid Fiber Reinforced Concrete

• Published in: Cement & concrete composites Vol. 34; no. 2; pp. 172 - 184
• Main Authors: Park, Seung Hun, Kim, Dong Joo, Ryu, Gum Sung, Koh, Kyung Taek
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2012
• Subjects: Blending; Blending effect; Cements; Fiber reinforced concretes; Fracture mechanics; Hybrid fiber composite; Macro-fiber; Micro-fiber; Steels; Strain hardening; Stress strain curves; Stress-strain relationships; Ultra High Performance Fiber Reinforced Concrete; Micro-fiber; Blending effect; Hybrid fiber composite; Macro-fiber; Ultra High Performance Fiber Reinforced Concrete
• ISSN: 0958-9465; 1873-393X
• DOI: 10.1016/j.cemconcomp.2011.09.009

The effects of blending fibers on the tensile behavior of Ultra High Performance Hybrid Fiber Reinforced Concrete (UHP-HFRC) are investigated. Four types of steel macro-fibers (of differing length or geometry) and one type of steel micro-fiber are considered. In producing the specimens, the volume content of the macro-fiber was held at 1.0%, whereas the volume content of the micro-fiber varied from 0.0% to 1.5%. The overall shape of tensile stress–strain curves of UHP-HFRC is primarily dependent upon the type of macro-fiber, although the addition of micro-fibers favorably affects the strain hardening and multiple cracking behaviors. UHP-HFRC produced from macro-fibers with twisted geometry provides the best performance with respect to post cracking strength, strain capacity and multiple micro-cracking behavior, whereas UHP-HFRC produced with long, smooth macro-fibers exhibits the worst performance.