The Experts below are selected from a list of 20334 Experts worldwide ranked by ideXlab platform
Kyoung-kyu Choi - One of the best experts on this subject based on the ideXlab platform.
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Punching strength of concrete footings based on the Compression Zone failure mechanism
Proceedings of the Institution of Civil Engineers - Structures and Buildings, 2020Co-Authors: Gia Toai Truong, Kyoung-kyu ChoiAbstract:A strength model based on the Compression Zone failure mechanism was developed to predict the punching shear strength of concrete footings without transverse reinforcement. The proposed model assum...
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Shear design for prestressed concrete beams based on Compression Zone failure mechanism
Proceedings of the Institution of Civil Engineers - Structures and Buildings, 2019Co-Authors: Jong-chan Kim, Gia Toai Truong, Kyoung-kyu ChoiAbstract:A new shear design method for prestressed concrete beams was developed based on the Compression Zone failure mechanism. The design method uses a sectional design approach, as used in current design...
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Laminated element analysis to predict the shear strength of concrete beams under distributed and concentrated loads
Engineering Structures, 2017Co-Authors: Jong-chan Kim, Kyoung-kyu ChoiAbstract:Abstract In the present study, an advanced analytical method was developed to evaluate the shear strength of slender concrete beams under distributed and concentrated transverse loads. The concrete shear capacity of the concrete beams is mainly provided by the Compression Zone of intact concrete since the tension Zone of the concrete beams is severely damaged by flexural cracks before shear failure. The concrete shear capacity is evaluated based on concrete material failure criteria addressing combined compressive normal and shear stresses in the Compression Zone along the critical shear crack surface. For complete analysis, laminated elements are applied to take into account the stress variation in each location of the Compression Zone. The proposed analytical method can be used not only to predict the shear strength, but also the location and the angle of the critical shear crack. The shear strength is predicted using the proposed method, and the results are compared to those of an experiment, covering a wide range of design parameters. In addition, analytical studies were performed for analytical beam models subjected to distributed and concentrated loads. Based on the analysis results, the effect of various parameters including the loading type (distributed and concentrated transverse loads) on the shear strength and the critical shear crack was investigated.
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Maximum Shear Strength of Slender RC Beams with Rectangular Cross Sections
Journal of Structural Engineering-asce, 2015Co-Authors: Kyoung-kyu Choi, Jong-chan Kim, Woo-chang Sim, Hong Gun ParkAbstract:AbstractIn the present study, the maximum shear strength of simply supported reinforced concrete beams with rectangular cross section was investigated. In beams with heavy shear reinforcement exceeding a certain limit, concrete crushing failure of the Compression Zone occurs before the yielding of the shear reinforcement. Thus, the maximum shear strength of such members is limited by the concrete crushing failure. In the present study, considering the shear-Compression failure mechanism of the Compression Zone, the maximum shear strength was defined by material failure criteria of the concrete subjected to the combined compressive and shear stresses. The proposed model was applied to specimens tested in the previous studies. The results showed that the proposed method predicted the maximum shear strengths of the specimens with a reasonable precision. Furthermore, a design equation for the maximum shear strength was proposed to secure the ductile flexural behavior of beams without early shear failure.
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Analytical model for shear strength of ordinary and prestressed concrete beams
Engineering Structures, 2012Co-Authors: Hong Gun Park, Soon-pil Kang, Kyoung-kyu ChoiAbstract:Abstract An analytical method employing the strain-based shear strength model was developed to predict the shear strength of prestressed concrete beams. The proposed method assumes that the shear force acting in a concrete beam is resisted primarily by the Compression Zone of intact concrete in the cross section. The shear capacity of the Compression Zone is evaluated at the inclined failure surface using the material failure criteria for concrete, considering the interaction with the compressive normal stress. Because the compressive stress is developed by the flexural action of the beam and the prestress applied to the cross section, the shear capacity is defined as a function of the flexural deformation and the prestress applied to the cross section. Then, the shear strength of the beam is determined at the intersection of the shear capacity curve and the shear demand curve. The proposed model was applied to existing test specimens. The results show that it can be used for both ordinary concrete beams and prestressed concrete beams.
James K Wight - One of the best experts on this subject based on the ideXlab platform.
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shear strength model for steel fiber reinforced concrete beams without stirrup reinforcement
Journal of Structural Engineering-asce, 2011Co-Authors: Hai H Dinh, Gustavo J Parramontesinos, James K WightAbstract:A simple model is presented to estimate the shear strength of steel fiber reinforced concrete (FRC) beams without stirrup reinforcement. The model was developed on the basis of observations from tests of 27 large-scale beams under monotonically increased concentrated loading. Three types of hooked steel fibers were evaluated in volume fractions ranging between 0.75% (59 kg/m3 or 100 lb/yd3) and 1.5% (118 kg/m3 or 200 lb/yd3). All but one beam failed in shear either prior to or after flexural yielding. In the proposed model, shear in steel FRC beams is assumed to be resisted by shear stress carried in the Compression Zone and tension transferred across diagonal cracks by steel fibers. Shear carried in the Compression Zone is estimated by using the failure criterion for concrete subjected to combined Compression and shear proposed by Bresler and Pister. The contribution from fiber reinforcement to shear strength, on the other hand, is tied to material performance obtained through standard ASTM 1609 four...
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unified shear strength model for reinforced concrete beams part i development
Aci Structural Journal, 2007Co-Authors: Kyoung-kyu Choi, Hong Gun Park, James K WightAbstract:This paper describes the development of a theoretical model to predict the shear strength of reinforced concrete beams with and without shear reinforcement. It was assumed that the shear strength of concrete beams can be determined from the failure of the Compression Zone of a beam cross section. The shear strength of the Compression Zone was evaluated, considering the interaction between the shear strength and normal stresses developed by the flexural moment. The failure mechanism of the Compression Zone changes from a tension failure to a Compression failure as the shear span-to-depth ratio decreases. The transition of the failure mechanism was properly addressed by considering the geometry of the beam and using material failure criteria of concrete. The proposed strength model can describe the failure mechanisms of both slender beams and deep beams with and without shear reinforcement. This model is verified and further discussed in a companion paper.
Hong Gun Park - One of the best experts on this subject based on the ideXlab platform.
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Maximum Shear Strength of Slender RC Beams with Rectangular Cross Sections
Journal of Structural Engineering-asce, 2015Co-Authors: Kyoung-kyu Choi, Jong-chan Kim, Woo-chang Sim, Hong Gun ParkAbstract:AbstractIn the present study, the maximum shear strength of simply supported reinforced concrete beams with rectangular cross section was investigated. In beams with heavy shear reinforcement exceeding a certain limit, concrete crushing failure of the Compression Zone occurs before the yielding of the shear reinforcement. Thus, the maximum shear strength of such members is limited by the concrete crushing failure. In the present study, considering the shear-Compression failure mechanism of the Compression Zone, the maximum shear strength was defined by material failure criteria of the concrete subjected to the combined compressive and shear stresses. The proposed model was applied to specimens tested in the previous studies. The results showed that the proposed method predicted the maximum shear strengths of the specimens with a reasonable precision. Furthermore, a design equation for the maximum shear strength was proposed to secure the ductile flexural behavior of beams without early shear failure.
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Analytical model for shear strength of ordinary and prestressed concrete beams
Engineering Structures, 2012Co-Authors: Hong Gun Park, Soon-pil Kang, Kyoung-kyu ChoiAbstract:Abstract An analytical method employing the strain-based shear strength model was developed to predict the shear strength of prestressed concrete beams. The proposed method assumes that the shear force acting in a concrete beam is resisted primarily by the Compression Zone of intact concrete in the cross section. The shear capacity of the Compression Zone is evaluated at the inclined failure surface using the material failure criteria for concrete, considering the interaction with the compressive normal stress. Because the compressive stress is developed by the flexural action of the beam and the prestress applied to the cross section, the shear capacity is defined as a function of the flexural deformation and the prestress applied to the cross section. Then, the shear strength of the beam is determined at the intersection of the shear capacity curve and the shear demand curve. The proposed model was applied to existing test specimens. The results show that it can be used for both ordinary concrete beams and prestressed concrete beams.
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punching shear strength of interior concrete slab column connections reinforced with steel fibers
Cement & Concrete Composites, 2007Co-Authors: Kyoung-kyu Choi, Hong Gun Park, Mahmoud Reda Taha, Arup MajiAbstract:Abstract A theoretical study was performed to investigate the punching shear strength of interior slab–column connections made of steel fiber reinforced concrete (FRC). In the steel FRC slab–column connection, the shear force applied to the critical section is resisted by both the Compression Zone and the tension Zone at the critical section. The shear capacity of the Compression Zone was defined by considering the interaction between the shear and the normal stresses developed at the critical section. The shear capacity of the tension Zone was defined by considering the post-cracking tensile strength of FRC. By using the shear capacity, a new strength model for the punching shear strength of steel FRC slab–column connections was developed. The proposed strength model was verified using existing test results and showed very good accuracy. For convenience in design, a simplified design equation was also developed.
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Punching shear strength of interior concrete slab–column connections reinforced with steel fibers
Cement & Concrete Composites, 2007Co-Authors: Kyoung-kyu Choi, Hong Gun Park, Mahmoud Reda Taha, Arup K. MajiAbstract:Abstract A theoretical study was performed to investigate the punching shear strength of interior slab–column connections made of steel fiber reinforced concrete (FRC). In the steel FRC slab–column connection, the shear force applied to the critical section is resisted by both the Compression Zone and the tension Zone at the critical section. The shear capacity of the Compression Zone was defined by considering the interaction between the shear and the normal stresses developed at the critical section. The shear capacity of the tension Zone was defined by considering the post-cracking tensile strength of FRC. By using the shear capacity, a new strength model for the punching shear strength of steel FRC slab–column connections was developed. The proposed strength model was verified using existing test results and showed very good accuracy. For convenience in design, a simplified design equation was also developed.
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unified shear strength model for reinforced concrete beams part i development
Aci Structural Journal, 2007Co-Authors: Kyoung-kyu Choi, Hong Gun Park, James K WightAbstract:This paper describes the development of a theoretical model to predict the shear strength of reinforced concrete beams with and without shear reinforcement. It was assumed that the shear strength of concrete beams can be determined from the failure of the Compression Zone of a beam cross section. The shear strength of the Compression Zone was evaluated, considering the interaction between the shear strength and normal stresses developed by the flexural moment. The failure mechanism of the Compression Zone changes from a tension failure to a Compression failure as the shear span-to-depth ratio decreases. The transition of the failure mechanism was properly addressed by considering the geometry of the beam and using material failure criteria of concrete. The proposed strength model can describe the failure mechanisms of both slender beams and deep beams with and without shear reinforcement. This model is verified and further discussed in a companion paper.
Hai H Dinh - One of the best experts on this subject based on the ideXlab platform.
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shear strength model for steel fiber reinforced concrete beams without stirrup reinforcement
Journal of Structural Engineering-asce, 2011Co-Authors: Hai H Dinh, Gustavo J Parramontesinos, James K WightAbstract:A simple model is presented to estimate the shear strength of steel fiber reinforced concrete (FRC) beams without stirrup reinforcement. The model was developed on the basis of observations from tests of 27 large-scale beams under monotonically increased concentrated loading. Three types of hooked steel fibers were evaluated in volume fractions ranging between 0.75% (59 kg/m3 or 100 lb/yd3) and 1.5% (118 kg/m3 or 200 lb/yd3). All but one beam failed in shear either prior to or after flexural yielding. In the proposed model, shear in steel FRC beams is assumed to be resisted by shear stress carried in the Compression Zone and tension transferred across diagonal cracks by steel fibers. Shear carried in the Compression Zone is estimated by using the failure criterion for concrete subjected to combined Compression and shear proposed by Bresler and Pister. The contribution from fiber reinforcement to shear strength, on the other hand, is tied to material performance obtained through standard ASTM 1609 four...
Arup Maji - One of the best experts on this subject based on the ideXlab platform.
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punching shear strength of interior concrete slab column connections reinforced with steel fibers
Cement & Concrete Composites, 2007Co-Authors: Kyoung-kyu Choi, Hong Gun Park, Mahmoud Reda Taha, Arup MajiAbstract:Abstract A theoretical study was performed to investigate the punching shear strength of interior slab–column connections made of steel fiber reinforced concrete (FRC). In the steel FRC slab–column connection, the shear force applied to the critical section is resisted by both the Compression Zone and the tension Zone at the critical section. The shear capacity of the Compression Zone was defined by considering the interaction between the shear and the normal stresses developed at the critical section. The shear capacity of the tension Zone was defined by considering the post-cracking tensile strength of FRC. By using the shear capacity, a new strength model for the punching shear strength of steel FRC slab–column connections was developed. The proposed strength model was verified using existing test results and showed very good accuracy. For convenience in design, a simplified design equation was also developed.