• Advances in concrete construction
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• v.8 no.2
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• pp.139-144
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• 2019

In this study, the mechanical properties of reactive powder concrete (RPC) with a constant cement to silica fume ratio of 4 were investigated. In the experimental program, reactive powder concretes with steel fiber at different ratios were produced. Five productions using quartz sand with a maximum grain size of 0.6 mm were performed. A superplasticizer with a ratio of 3% of the cement was used for all productions. $40{\times}40{\times}160mm$ prismatic specimens were prepared and tested for flexural and compression. The specimens were exposed to two different curing conditions as autoclave and standard curing condition. Autoclave exposure was performed for 3 hours under a pressure of 2 MPa. It was observed that the compressive strength of concrete, along with the flexural strength exposed to autoclave was quite high compared to the strength of concretes subjected to standard curing. The results obtained indicated that the compressive strength, along with the flexural strength of autoclaved concrete increased as the amount of cement used increases. Approximately 15% increase in flexural strength was achieved with a 4% steel fiber addition. The maximum compressive strength that has been reached is over 210 MPa for reactive powder concrete for the same steel fiber ratio and with a cement content of $960kg/m^3$. The relationship between compressive strength and flexural strength of reactive powder concrete exposed to both curing conditions was also identified.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.6
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• pp.47-58
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• 2004

As concrete structures are getting larger, higher, longer and more specialized, it is more required to develop steel fiber concrete and apply to the real world. In this research, it is aimed to have fatigue strength examined, varying the steel fiber content of 0%, 0.75%, 1.00%, 1.25% by experimental study of fatigue behavior of the steel fiber reinforced concrete continuous beams under cyclic loading. The ultimate load and initial load of flexural cracking were measured by static test. In addition, the load versus strain relation, load versus deflection relation, crack pattern and fracture mode by increasing weight were observed. On the other hand, the crack propagation and the modes of fracture according to cycle number and the relation of cyclic loading to deflection relation and strain relation were investigated by fatigue test. As the result of fatigue test, continuous beam without steel fiber was failed at 60 ~ 70% of The static ultimate strength and it could be concluded that fatigue strength to two million cyclic loading was arround 67.2% by S-N curve. On the other hand, that with steel fiber was failed at 65 ~ 85% of the static ultimate strength and it could be concluded fatigue strength to two million cyclic loading around 71.7%.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.10
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• pp.181-190
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• 2019

In this study, four reinforced concrete coupling beams were subjected to cyclic lateral loading test to evaluate the structural performance of coupling beam according to volume fraction of steel fiber. For this purpose, the volume fraction of steel fiber(0%, 1%, 2%) and transverse reinforcement spacing were determined as the main parameter. According to the test results, the maximum strength of D-40C-s100-0 was 1.15, 1.13, 1.05 times higher than D-40C-s300-0, D-40C-s300-1, D-40C-s300-2, respectively. The maximum strength of coupling beams with mitigated rebar details increases as the volume fraction of steel fiber increases. Although steel fiber 2% reinforced specimen(D-40C-s300-2) did not satisfy the amount of transverse reinforcement required for seismic design of coupling beam, the overall performance including to maximum strength, ductility and energy dissipation capacity was similar to the control specimen(D-40C-s100-0). As a result, the use of steel fiber with 2% reinforcement can partially replace the transverse reinforcement in diagonally reinforced concrete coupling beam.

• Journal of Industrial Technology
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• v.19
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• pp.163-172
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• 1999

This study is conducted on the flexural toughness and flexural fatigue test to fine the mechanical properties of steel fiber reinforced rapid-set cement concrete. Experimental investigation is examined according to fiber contents(0, 0.4, 0.7, 1.0, 1.5%), fiber aspect ratio(58, 60, 83), fiber type (hooked, crimped fiber), and cement type (normal portland & rapid-set cement). The principal results obtained through this study are as follows; toughness and fatigue resistance tend to considerably increase with fiber contents, fiber aspect ration. And hooked fiber is improved better than crimped fiber. Concrete using rapid set cement is increased strength properties compared with concrete using normal portland cement, but relative strength properties behavior and fatigue resistance show a tendency to decrease a little.

• Journal of the Korea Concrete Institute
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• v.27 no.3
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• pp.283-290
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• 2015

This paper proposes a method for predicting flexural strength of hybrid steel fiber-reinforced ultra-high strength concrete beams. It includes an experimental test framework and associated numerical analyses. The experimental program includes flexural test results of hybrid steel fiber-reinforced ultra-high strength concrete beams with steel fiber content of 1.5% by volume. Tensile softening characteristics play an important role in the structural behavior of steel fiber-reinforced ultra high performance concrete. Tension softening modeling is carried out by using crack equation based on fictitious crack and inverse analysis in which load-crack mouth opening displacement relationship is considered. The comparison of moment-curvature curves of the numerical analysis results with the test results shows a reasonable agreement. Therefore, the numerical results confirms that good prediction of flexural behavior of steel fiber-reinforced ultra high strength concrete beams can be achieved by employing the proposed method.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.62-65
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• 2000

Potentially significant engineering advantages can be gained by the incorporation of steel fibers in tension-weak concrete. A variety of tests have been developed to measure and quantify the improvements achievable in steel fiber reinforced concrete. An objective of the study is to experimentally investigate the flexural fatigue behavior of steel-reinforced concrete with a experimental variables such as steel fiber types. To predict the behavior of steel reinforced structural componets under fatigue conditions.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.205-208
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• 2002

This study is performed to examine the flowability and filling ability of steel fiber reinforced high performance concrete. For the estimation of the flowability and filling ability, slump flow, box height difference and L-shape filling appearence are measured and compared. The test result shows that the slump flow is $60{\pm}5cm$ to make no difference with containing steel fiber, box height difference is increased with increasing steel fiber and L-shape filling appearence is to bad with increasing steel fiber. But, proper containg of steel fiber is considered to be applied for high performance concrete without decreasing of slump flow and filling ability.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.251-254
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• 2005

This study will have to define the shear strengthening effects of steel fiber in beam and column levels, as well as to suggest estimation method of maximum shear capacity of structural members. From review of literature surveys and perform structural member test results, following conclusion can be made; In beam level, steel fiber strengthening factor is suggested from the tensile splitting test results and beam test results. After suggesting shear capacity of beam without stirrups and beam with stirrups by proposed steel fiber strengthening factor, proposed equation is possible to evaluate the shear capacity of beam. In column level, with column test results and proposed steel fiber strengthening factor, shear capacity equation of steel fiber reinforced concrete in column is suggested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.1
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• pp.139-145
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• 2000

In this experimental program specimens. designed by the test variables, such as percentage of steel fiber incorporated, were constructed and tested to evaluate the flexural performance of reinforced steel fiber concrete beams. Based on the test results reported in this study, the following conclusions are made. Comparing with the load-displacement relationship of standard specimen, specimen over 0.5% of steel fiber incorporated, could be improved significantly flexural performance, such as capacity, ductility, and crack pattern. As increasing in quantity of steel fiber incorporated(0.5%~2.0%), the flexural strength of each specimen was shown the enhancement of 13%~40% in comparision with the standard specimen BSS.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.3
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• pp.197-203
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• 2013

In this study, the creep behaviors of amorphous steel fiber-reinforced concrete were investigated. Two different types of tests were carried out to evaluate the effect of amorphous steel fibers on the creep of concrete: compressive creep test and tensile creep test. Fiber volume fractions used in the test were 0.2% and 0.4% for tensile specimens, and 0.2% and 0.3% for compressive specimens. Based on the test results, the addition of fiber volume fraction of 0.2% into concrete could significantly reduce both compressive and tensile creep.