• 콘크리트학회논문집
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• 제23권1호
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• pp.13-22
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• 2011

이 논문에서는 전편 논문에서 제안한 부정정 스트럿-타이 모델 및 하중분배율 결정식을 ACI 318M-08 스트럿-타이 모델 설계기준에 적용하여 파괴실험이 수행된 51개 연속지지 철근콘크리트 깊은 보의 극한강도를 평가하였다. 또한 연속 깊은 보의 극한강도를 실험식, 실험 및 이론 전단강도모델에 기초한 설계기준, 그리고 현 스트럿-타이 모델설계기준 등으로 평가하고, 그 결과를 이 연구의 방법에 의한 결과와 비교분석하여 이 연구에서 제안한 방법의 적합성을 검증하였다. 이 연구의 방법은 기존의 여러 방법에 비해 극한강도를 비교적 양호하게 평가하였으며, 또한 극한강도평가 시 연속 깊은 보의 강도 및 거동에 영향을 미치는 전단경간비, 콘크리트의 압축강도, 그리고 휨철근비 등 주요설계변수들의 영향을 기존 방법들에 비해 정확하고 일관성 있게 반영하였다. 따라서 이 연구의 방법은 부정정 스트럿-타이 모델 방법을 이용한 연속 깊은 보의 합리적이고 실용적인 설계를 가능하게 할 것으로 판단된다.

• Computers and Concrete
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• 제12권3호
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• pp.243-259
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• 2013

Recent developments in Artificial Intelligence (AI) and computational intelligence have made it viable in the construction industry and structural analysis. This study usesthe Adaptive Network-based Fuzzy Inference System (ANFIS) as a modelling tool to predict the strain in tie section for High Strength Self Compacting Concrete (HSSCC) deep beams. 3773 experimental data were collected. The input data andits corresponding strains in tie section as output data were recorded at all loading stages. Results from ANFIS are compared with the classical linear regression (LR). The comparison shows that the ANFIS's results are highly accurate, precise and satisfactory.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.567-572
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• 1998

Structural behavior of R/C deep beams was investigated and compared to those of specimens with CFRP Grids. Test results show that the crushing of compression strut for the unstrengthened R/C deep beams is changed to the group of several diagonal cracks at mid-depth within the sheat span. Strengthened specimens grow to be more ductile after the redistribution of internal force on the CFRP Grids. The failure mode and variations of strains in the specimens are dependent on the shear span-to-depth ratio. The lower the shear span-to-depth ratio, the bigger failure load and the less variations in strain are observed. Additional anchorage of CFRP Grids does not only cause the improvement in the internal resistance, but also control the brittle shear failure of specimen after reaching the maximum loads.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.903-906
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• 2001

The objective of this experimental study was to understand the effect of horizontal shear bar on the shear behavior of R.C. deep beams. Therefore, in the test program, the horizontal shear bar ratio($\rho_{sh}$) and shear span-to-overall depth ratio(a/h) are considered as two main variables. Test results indicate that for deep beams with a/h equal to 1.0, horizontal shear bar is less efficient in restricting the diagonal crack width development and enhancing the ultimate shear strength. So, it can be concluded that shear resistance of horizontal shear bar is related to a/h rather than clear span-to-effective depth ratio($l_{n}$/d) recommended in ACI code.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.532-535
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• 2004

This paper presents a nonlinear finite element analysis procedure for the prediction of shear strength of reinforced concrete deep beams. A computer program, named RCAHESTC(Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. Material nonlinearity is taken into account by comprising tensile. compressive and shear models of cracked concrete and a model of reinforcing steel. The smeared crack approach is incorporated. The proposed numerical method for the prediction of shear strength of reinforced concrete deep beams is verified by comparison with the reliable experimental results.

• Structural Engineering and Mechanics
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• 제4권4호
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• pp.437-450
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• 1996

A study on the behaviour of fibre reinforced concrete deep beams with and without web openings is carried out using nonlinear finite element analysis. Eight node isoparametric plane stress elements are employed to model the fibre reinforced concrete materials. Steel bars are treated using a compatible three node truss elements. The constitutive equations for fibre reinforced concrete materials take into account the softening effect of co-existing shear strains. Element stiffness at each step is formulated based on the tangent modulus at the current level of principal strains. Transformation between principal directions and global coordinate system is imposed. Comparison of analytical results with experimental values indicates reasonably good agreement. The proposed numerical model can be used to study the behaviour of this composite structures of practically any geometries.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.193-194
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• 2009

본 연구에서는 프리텐션 콘크리트 깊은 보의 강도 및 거동 특성을 모두 반영하여 강도해석을 수행할 수 있는 부정정 스트럿-타이 모델을 제안하였다. 또한 현행 설계기준의 스트럿-타이 모델 방법을 부정정 스트럿-타이 모델을 이용한 프리텐션 콘크리트 깊은 보의 강도해석에 합리적으로 적용하기 위해 수직 트러스 메커니즘에 의해 전달되는 하중의 크기 즉 부정정 스트럿 타이 모델의 하중 분배율을 제안하였다.

• Structural Engineering and Mechanics
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• 제46권6호
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• pp.853-868
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• 2013

The comparison of the effectiveness of artificial neural network (ANN) and linear regression (LR) in the prediction of strain in tie section using experimental data from eight high-strength-self-compact-concrete (HSSCC) deep beams are presented here. Prior to the aforementioned, a suitable ANN architecture was identified. The format of the network architecture was ten input parameters, two hidden layers, and one output. The feed forward back propagation neural network of eleven and ten neurons in first and second TRAINLM training function was highly accurate and generated more precise tie strain diagrams compared to classical LR. The ANN's MSE values are 90 times smaller than the LR's. The correlation coefficient value from ANN is 0.9995 which is indicative of a high level of confidence.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.609-614
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• 1997

Recently, many researchers have performed R&D about strengthening of R/C with steel plates, carbon fiber sheets. aramid fiber sheets and glass fiber sheets, and so on. However most of research were limited in study of flexural strengthening of R/C beams. This paper shows the results of an experimental study on shear reinforcement of deep beams using Glass Fiber Sheet in relation to shear-span ratio. strengthening orientation and anchorage. The results prove that shear failure is governed by reinforced orientation. adherence and anchorage. Additional anchorage of fibers does not only cause the improvement in the internal resistance, but also control the brittle shear failure of specimen after reaching the maximum load.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.147-150
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• 2005

This paper presents a method for the load capacity assesment of reinforcement concrete deep beams using nonlinear finite element analysis. A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. From the results, determine the reliability index for the failure base from the Euro Code. Then, calculated additional reduction coefficient to satisfy the goals from the reliability analysis. The proposed numerical method for the load capacity assesment of reinforced concrete deep beams is verified by comparison with the others methods