• Journal of the Korea Institute of Building Construction
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• v.3 no.1
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• pp.85-91
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• 2003

This study aims to provide basic data that can be applied to construct real structures. For this, an experimental structure was manufactured to identify durability according to age of fiber-reinforced concrete which contains fiber reinforcement materials (polypropylene fiber, steel fiber, cellulose fiber) and structural property about flexural behavior and destruction of reinforced concrete beam, and a relation between load and deflection, crack and destruction according to increase of load and ductility capacity was examined. Fiber-reinforced concrete materials and other constructional materials were experimented and the result is presented as follows: The results obtained through material test of concrete and static experiment of members usings 1. The experiment shows that compressive strength of fiber-reinforced concrete was lower than that of non-reinforced concrete. 2. As a result of strength experiment according to different kinds of fiber, compressive strength of an experimented structure that contains cellulose fiber was the highest when age was 28. 3. When deflection of reinforced concrete beam was examined, it was reported that ductility capacity of the experimented structure that contains fiber-reinforced concrete was raise than that of non-reinforced concrete.

• Computers and Concrete
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• v.18 no.3
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• pp.355-366
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• 2016

This paper reports the testing of concrete slabs reinforced with CFRP prestressed concrete prisms(PCP) on the flexural behavior. Four concrete slabs were tested, a reference slab reinforced with steel bars, and three slabs reinforced with CFRP prestressed concrete prisms (PCP). All slabs were made with dimensions of 600mm in width, 2200mm in length and 150 in depth. All concrete slabs reinforced with CFRP prestressed concrete prisms(PCP) exhibited CFRP bar rupture failure mode. It was shown that the application of the CFRP prestressed prisms can limit service load deflections and crack width, the increased level of prestress in the CFRP prestressed prism positively affected the maximum crack width. The deflection of concrete slabs reinforced with CFRP prestressed prisms decreased as prestress in the CFRP prestressed prism increased.

• Structural Engineering and Mechanics
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• v.11 no.3
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• pp.301-314
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• 2001

The purpose of this experimental study is to investigate the damage mechanism due to shear-fatigue behavior of high-strength reinforced concrete beams under repeated loading. The relationship between the number of cycles and the deflection or strain, the crack growths and modes of failure with the increase of number of cycles, fatigue strength, and S-N curve were observed through a fatigue test. Based on the fatigue test results, high-strength reinforced concrete beams failed at 57-66 percent of static ultimate strength for 2 million cycles. The fatigue strength at 2 million cycles from S-N curves was shown as about 60 percent of static ultimate strength. Compared to normal-strength reinforced concrete beams, fatigue capacity of high-strength reinforced concrete beams was similar to or lower than fatigue capacity of normal-strength reinforced concrete beams. Fatigue capacity of normal-strength reinforced concrete beams improved by over 60 percent.

• Advances in concrete construction
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• v.5 no.3
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• pp.257-270
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• 2017

An experimental investigation was carried out to study the strength and behavior of reinforced cement concrete (RCC) frames with ferrocement and fiber reinforced concrete infill panel. Seven numbers of $1/4^{th}$ scaled down model of one bay-three storey frames were tested under reverse cyclic loading. Ferrocement infilled frames and fiber reinforced concrete infilled frames with varying volume fraction of reinforcement in infill panels viz; 0.20%, 0.30%, and 0.40% were tested and compared with the bare frame. The experimental results indicate that the strength, stiffness and energy dissipation capacity of infilled frames were considerably improved when compared with the bare frame. In the case of infilled frames with equal volume fraction of reinforcement in infill panels, the strength and stiffness of frames with fiber reinforced concrete infill panels were slightly higher than those with ferrocement infill panels. Increase in volume fraction of reinforcement in the infill panels exhibited only marginal improvement in the strength and behavior of the infilled frames.

• Smart Structures and Systems
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• v.2 no.1
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• pp.81-100
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• 2006

To calculate the shear capacity of concrete beams reinforced with fibre-reinforced polymer (FRP), current shear design provisions use slightly modified versions of existing semi-empirical shear design equations that were primarily derived from experimental data generated on concrete beams having steel reinforcement. However, FRP materials have different mechanical properties and mode of failure than steel, and extending existing shear design equations for steel reinforced beams to cover concrete beams reinforced with FRP is questionable. This paper investigates the feasibility of using artificial neural networks (ANNs) to estimate the nominal shear capacity, Vn of concrete beams reinforced with FRP bars. Experimental data on 150 FRP-reinforced beams were retrieved from published literature. The resulting database was used to evaluate the validity of several existing shear design methods for FRP reinforced beams, namely the ACI 440-03, CSA S806-02, JSCE-97, and ISIS Canada-01. The database was also used to develop an ANN model to predict the shear capacity of FRP reinforced concrete beams. Results show that current guidelines are either inadequate or very conservative in estimating the shear strength of FRP reinforced concrete beams. Based on ANN predictions, modified equations are proposed for the shear design of FRP reinforced concrete beams and proved to be more accurate than existing equations.

• Steel and Composite Structures
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• v.34 no.6
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• pp.909-927
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• 2020

This paper addresses the results of an experimental study involving 10 partially encased composite columns under concentric and eccentric compressive loads. Parameters such as slenderness ratio, ordinary reinforced concrete and fiber reinforced concrete, load eccentricity and bending axis were investigated. The specimens were tested to investigate the effects of replacing the ordinary reinforced concrete by fiber reinforced concrete on the load capacity and behavior of short and slender composite columns. Various characteristics such as load capacity, axial strains behavior, stiffness, strains on steel and concrete and failure mode are discussed. The main conclusions that may be drawn from all the test results is that the behavior and ultimate load are rather sensitive to the slenderness of the columns and to the eccentricity of loading, specially the bending axis. Experimental results also indicate that replacing the ordinary reinforced concrete by steel fiber reinforced concrete has no considerable effects on the load capacity and behavior of the short and slender columns and the proposed replacement presented very good results.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.587-592
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• 2002

Fiber reinforced concrete has been used for tunnel lining and rehabilitation of old structures. Recently, structural synthetic fiber was developed to overcome the corrosive properties of steel fibers. Fibers play a role to increase the tensile and cracking resistance of concrete structures. The Post cracking behavior must be clarified to predict cracking resistance of fiber reinforced concrete. The purpose of the present study is to develop a realistic analysis method for post cracking behavior of synthetic fiber reinforced concrete members.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.156-161
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• 1993

This paper is to develop steel fiber reinforced polymer-impregnated concrete(SFPIC) by impregnation polymer impregnate into hardened steel fiber reinforced concrete(SFRC). Steel fiber induces ductile behavior and polymer impregnant increase compressive strength. Steel fiber reinforced polymer-impregnated concrete specimens are prepared with fiber contents of 0.0, 1.5, 2.0, 2.5% and tested to obtain uni-axial and bi-axial compression strengths, tensile strength and flexural strength. The strength and mechanical properties of normal concrete, SFRC, SFPIC are compared.

• Structural Engineering and Mechanics
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• v.12 no.5
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• pp.459-474
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• 2001

The complete moment-curvature curves of doubly reinforced concrete beams made of normal- or high-strength concrete have been evaluated using a newly developed analytical method that takes into account the stress-path dependence of the constitutive properties of the materials. From the moment-curvature curves and the strain distribution results obtained, the post-peak behavior and flexural ductility of doubly reinforced normal- and high-strength concrete beam sections are studied. It is found that the major factors affecting the flexural ductility of reinforced concrete beam sections are the tension steel ratio, compression steel ratio and concrete grade. Generally, the flexural ductility decreases as the amount of tension reinforcement increases, but increases as the amount of compression reinforcement increases. However, the effect of the concrete grade on flexural ductility is fairly complicated, as will be explained in the paper. Quantitative analysis of such effects has been carried out and a formula for direct evaluation of the flexural ductility of doubly reinforced concrete sections developed. The formula should be useful for the ductility design of doubly reinforced normal- and high-strength concrete beams.

• Computers and Concrete
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• v.30 no.4
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• pp.289-299
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• 2022

Based on the random cracking theory, the cylinder RVE model of reinforced concrete is established and the damage process is divided into three stages as the evolution of the cracks. The stress distribution along longitude direction of the concrete and the steel bar in the cylinder model are derived. The equivalent elastic modulus of the RVE are derived and the user-defined field variable subroutine (USDFLD) for the equivalent elastic modulus is well integrated into the ABAQUS. Regarding the tensile rebars and the concrete surrounding the rebars as the equivalent homogeneous transversely isotropic material, and the FEM analysis for the reinforced concrete beams is conducted with the USDFLD subroutine. Considering the concrete cracking and interfacial debonding, the macroscopic damage process of the reinforced concrete beam under four-point bending loading in the simulation. The volume fraction of rebar and the cracking degree are mainly discussed to reveal their influence on the macro-performance and they are calibrated with experimental results. Comparing with the bending experiment performed with 8 reinforced concrete beams, the bending stiffness of the second stage and the ultimate load simulated are in good agreement with the experimental values, which verifies the effectiveness and the accuracy of the improved finite element method for reinforced concrete beam.