• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.185-196
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• 1998

이 논문은 직사각형 단면을 갖는 철근콘크리트 보에서 휨전단균열(Flexural-Shear Crack)이 원인을 규명하기 위해 모두 16개의 보를 실험한 결과를 기술한 것이다. 실험에 이용된 콘크리트보는 전단균열에 영향을 준다고 생각되는 몇 가지 요소를 인위적으로 소거 도는 고립되도록 특수하게 제작된 것이다. 이러한 특수보의 실험결과를 같은 재원을 갖는 보통의 정상보의 결과와 직접 비교하여서 그 차이를 분석함으로써 휨전단 균열의 발생원인을 규명하였다. 그 결과, 일반적인 콘크리트보에서의 휨전단균열 발생은 철근과 콘크리트의 경계면의 부착현상과 매우 밀접한 관련이 있는 것으로 나타났다. 또한 발생된 휨전단균열의 안정성은 주철근을 따라 발생되는 수평균열의 크기에 직접적인 영향을 받고 있는 것으로 나타났다. 본 연구에서 나타난 몇 가지 사실은 현재 사용중인 전단설계규준의 근본을 이루는 전단 위험단면개념과는 상반되는 것도 있었다. 실험에서 알아낸 사실을 근거로 전단파괴기구에 대한 새로운 가설을 제안하였다. 이 새 가설은 지금까지 잘 설명되지 않은 휨전단균열의 발생과 진행에 대한 원인 및 과정을 상당히 잘 설명해주고 있다고 생각된다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.138-147
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• 2011

The objective of this study which it sees direct shear stress and comparative analysis of flexural shear stress leads and it is a shear stress analysis which it follows in load direction of the structure which uses Perfobond Rib shear connectors. To analyze direct shear stress, five Perfobond Rib shear connect experiments were fabricated with five variables and conducted Push-out Tests. After experiments, mechanism of Perfobond Rib shear connector was examined and direct shear formula was proposed based on primary factors which influence direct shear stress. Also, for the analysis of flexural shear steel-concrete composite slab specimens were fabricated and static flexural test. Based on the static flexural test it analyzed the flexural behavior and the flexural shear stress it calculated. Direct shear stress and EN 1994-1-1 to lead and be calculated, it compared the flexural shear stress and it analyzed in about the shear resistance stress which it follows in load direction.

• Magazine of the Korea Concrete Institute
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• v.9 no.6
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• pp.207-216
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• 1997

본연구는 축방향 변형 구속이 고강도 콘크리트 휨부재의 휨 전단거동에 미치는 영향을 조사하기 위한 것으로, 수화열과 건조수축에 기인하는 축방향 변형과 재하에 의한 축방향 변형을 구속한 부재 및 무구속 부재에 대하여 휨파괴와 전단파괴 실험을 실시하였다. 타설 직후부터 축변형을 구속한 실험체의 재하시 강성은 재하전의 구속으로 발생한 관통균열의 영향을 받아 무구속 실험체의 강성보다 낮지만, 재하시의 축변형 구속에 따른 압축구속력의 상승으로 인하여 강성의 크기는 역전되었다 축변형이 완전히 구속된 휨부재의 휨강도는 무구속 부재보다 20%이상 상승하지만 변형능력은 감소하는 것으로 나타났으며, 재하전의 축변형 구속에 의한 관통균열(균열폭 0.1mm 미만)은 부재의 전단내력 및 전단균열 진전 형상에 영향을 미치지 않았다.

• Journal of Korean Society of Steel Construction
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• v.24 no.2
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• pp.137-147
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• 2012

This paper describes an experimental study on the mechanical characteristic and behavior of a structure that has a joint between the reinforced concrete (RC) member and steel plate concrete (SC) member. An out-of-plane flexural test on an L-type test specimen and in-plane shear test on an I-type test specimen were carried out by means of repeated cyclic loading until their failure. Based on the results, the former showed pull-out failure mode of anchored vertical bars while the latter exhibited flexural failure mode of the basement member. These results reveal that the maximum capacity of the specimens is 96% and 82%, respectively, compared with the theoretical value.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.257-267
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• 2008

Results of seventy-seven specimens tested by this study and previous research were collected and evaluated to propose the flexural strength and shear strength for flexural members with steel fiber concrete. For strength evaluation, structural parameters such as compressive strength, steel fiber content, tensile reinforcement ratio, and shear span to effective depth ratio are involved. The proposed equations for flexural and shear strength are regarded to give a good prediction for the strength of steel fiber reinforced composite and/or RC beams to compare with equations by previous researchers. Especially, the proposed shear strength equation in this study shows the lowest the mean value, the coefficient of variation and the error ratio among predictions by several equations. Therefore, equations for shear strength and flexure strength, which are proposed in this study are to be useful measure to predict the actual behavior and failure mode of steel fiber reinforced composite beams.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.2
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• pp.76-82
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• 2006

The concrete shear strength of FRP Bar reinforced concrete beam according to the variation of flexural reinforcement ratio was investigated. A number of experimental result showed that the concrete shear strength was lower than that of RC beam, but it was increased according to the increasement of reinforcement ratio. Shear strength correction factors considering the kind and reinforcement ratio of FRP Bar was proposed using the proposed formula in the literature and regression analysis of the experimental result.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3A
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• pp.259-266
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• 2009

This study is to develop equations that consider the elastic modulus ratio of FRP bar and steel reinforcement, shear span to depth ratio, and flexural reinforcement ratio of FRP bar, to determine concrete shear strength of FRP reinforced concrete beams without shear reinforcement. As experimental parameters, 2 types of FRP bar, 3 types of shear span to depth ratio, and 3 types of flexural reinforcement were used. Experimental results for two of shear span to depth ratio were quoted from previous study to evaluate effect of shear span to depth ratio in more detail. Shear strength correction factors needed for evaluating concrete shear strength were proposed from regression analysis using above experimental results. Equations suggested from this study and other codes were examined and compared with 31 experimental results available in the literature. From this comparison, it could be known that the equation suggested from this study gives the most approaching result to experimental results.

• Journal of the Korean Geophysical Society
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• v.4 no.3
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• pp.219-226
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• 2001

본 연구에서는 주기적인 하중하에서의 철근콘크리트 기둥의 이력응답거동을 예측할 수 있는 해석적인 모델의 개발을 다루고 있다. 철근콘크리트 기둥의 비탄성 휨, 전단 및 휨-전단 변형은 개발된 모델을 통하여 주기적인 변위하에서 검토되었다. 개발된 모델들을 포함한 해석치와 실험치와의 비교분석을 통하여 본 연구에서 개발된 모델들의 검증을 실시하였고, 이 비교분석을 통하여 휨-전단간의 상호작용의 중요성을 강조하였으며, 본 연구에서 개발된 모델들의 정확성, 효율성 및 타당성을 입증하였다.

• The Journal of Engineering Research
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• v.4 no.1
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• pp.151-158
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• 2002

본 연구에서는 주기적인 하중하에서의 철근콘크리트 기둥의 이력응답거동을 예측할 수 있는 해석적인 모델의 개발을 다루고 있다. 철근콘크리트 기둥의 비탄성 휨, 전단 및 휨-전단 변형은 개발된 모델을 통항 주기적인 변위하에서 검토되었다. 개발된 모델들을 포함한 해석치와 실험치와의 비교분석를 통하여 본 연구에서 개발된 모델들의 검증을 실시하였고, 이 비교분석을 통하여 휨-전단간의 상호작용의 중요성을 강조하였으며, 본 연구에서 개발된 모델들의 정확성, 효율성 및 타당성을 입증하였다.

• Journal of Korean Society of Steel Construction
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• v.20 no.4
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• pp.539-548
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• 2008

This study aims to determine the applicability of the previously published T-type modular profile beam in the manner of producing specimens designed specially for the said purpose, determining their bending and shear behaviors depending on the presence of shear reinforcement, and analyzing the results in comparison with the theoretical equation of plastic deformation. The modular profile beam contributes to bending and shear resistance with the addition of the profile to the form function, and enhances the molding performance through the modular concept. The experimental results showed that the TS series specimens with shear reinforcement have bending behaviors superior to those of the T series specimens without shear reinforcement, which suggests that the used shear reinforcement appropriately bears the shear force. However, it was considered that all the specimens except for the T1-1 specimen failed to have adequate bending performance because of the intermodular slipping caused by the shear failure of the bolts. It is expected that further studies on the T-type modular profile beam, in which shear connectors will be considered as a variable,be performed to develop optimal intermodular connection methods.