Abstract
Recognizing that steel fibers can supplement the brittle tensile characteristics of concrete, many studies have been conducted on the shear performance of steel fiber reinforced concrete (SFRC) members. However, previous studies were mostly focused on the shear strength and proposed empirical shear strength equations based on their experimental results. Thus, this study attempts to estimate the strains and stresses in steel fibers by considering the detailed characteristics of steel fibers in SFRC members, from which more accurate estimation on the shear behavior and strength of SFRC members is possible, and the failure mode of steel fibers can be also identified. Four shear behavior models for SFRC members have been proposed, which have been modified from the softened truss models for reinforced concrete members, and they can estimate the contribution of steel fibers to the total shear strength of the SFRC member. The performances of all the models proposed in this study were also evaluated by a large number of test results. The contribution of steel fibers to the shear strength varied from 5% to 50% according to their amount, and the most optimized volume fraction of steel fibers was estimated as 1%–1.5%, in terms of shear performance.
Highlights
Fiber-reinforced concretes (FRCs) are made with various types of fiber materials, such as steel, carbon, nylon, and polypropylene, which are generally known to have enhanced tensile performance and crack control capability compared to conventional concrete [1,2,3,4,5,6,7]
The shear strength models proposed in this study are the smeared crack models that were modified from the softened truss models (STM), which can predict the shear behavior of steel fiber reinforced concrete (SFRC) members relatively fast, compared to the discrete crack model, by defining the steel fibers on the average that are randomly distributed in concrete without any constant direction
The steel fiber volume fraction of the collected specimens ranged from 0.22% to 2.0%, and the size of steel fibers used in the specimens ranged widely from the small ones with the length of 25.4 mm and the diameter of 0.25 mm to the big ones with the length of 60 mm and the diameter of 0.8 mm
Summary
Fiber-reinforced concretes (FRCs) are made with various types of fiber materials, such as steel, carbon, nylon, and polypropylene, which are generally known to have enhanced tensile performance and crack control capability compared to conventional concrete [1,2,3,4,5,6,7]. There are only few shear behavior models for SFRC members, and they mostly modified the tensile stress-strain relationship of concrete to fit for SFRC members. They are able to estimate the shear behavior of SFRC members, they cannot identify the strains and stresses in steel fibers, which make it difficult to assess the enhancement of shear performance in detail according to the properties of steel fibers. Since the proposed models can estimate the stresses in steel fibers, an attempt was made to evaluate the effectiveness of the steel fibers as a shear reinforcing material by assessing the contribution of the steel fibers to the total shear resistance of SFRC beams
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
