Research & Publications from OSES Engineering in Ottawa
Shear Stress Prediction: Steel Fiber-Reinforced Concrete Beams Without Stirrups
American Concrete Institute - Structural Journal
Document Name: 108-S29
Author(s): Sam (Haisam) Yakoub
Publication: ACI- Structural Journal
Keywords: absolute reduction factor; failure; geometry factor; shear stress; steel fibre-reinforced concrete; strain; volume fraction
Date: May 1, 2011
This paper develops an equation to predict steel fibre contribution to the shear strength of steel fibre-reinforced concrete (SFRC). This equation is used to modify the CSA A23.3-04 general shear design method and Bažant and Kim equations so that the modified relations safely predict the shear strength of SFRC without stirrups. This paper analyzes 218 shear failure tests previously conducted on SFRC without stirrups and 72 tests on reinforced concrete—with no stirrups and no steel fibres—to verify the applicability, accuracy, and efficiency of the two equations developed in this paper and five other equations from the literature. Furthermore, it shows that hooked steel fibres are not as efficient as crimped fibres. The round fibre is among the most efficient fibres used in those tests. Moreover, it recommends a procedure to calculate steel fibre geometry factors, another factor to evaluate engineering equations, and further research on different SFRC aspects.
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