Flexural Impact Behavior of Cellulose and Hybrid Fibers Reinforced Concrete Beams

In order to research the firer type effect on the impact behavior, the flexural impact performance of concrete reinforced with natural cellulose (Buckeye Ultra-Fiber 500 ), steel fibers and hybrid fibers were investigated systematically. The initial-crack impact life, the failure impact life and impact ductility are analyzed with statistic analysis method. The experimental results indicate that cellulose fibers can highly improve the initial-crack impact performance and steel fibers can remarkably improve the failure impact performance. When the cellulose fiber content is 1.2 kg/m³, the initial-crack impact life of cellulose fiber reinforced concrete is 2.4 times higher than that of plain concrete, and is similar to that of concrete reinforced with steel fibers of 64 kg/m³. When the reinforced concrete with steel fibers of 78 kg/m³ mix with cellulose fibers of 1.0 kg/m³, the failure impact life is 8.1 times higher than that of plain concrete. Reinforced concrete with cellulose and steel hybrid fibers can remarkably improve the flexural impact performance and can fully have the advantages of the two fibers.