• 콘크리트학회논문집
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• 제24권2호
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• pp.147-156
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• 2012

최근 몇 년간 보-기둥 접합부에 영향을 줄 수 있는 경사기둥을 포함한 비정형 구조 시스템을 가진 초고층 빌딩이 증가하고 있다. 경사기둥-보 접합부에 외력이 작용 시 전단과 휨 모멘트의 분포가 정형화된 보-기둥 접합부와 상이하여 접합부의 파괴모드, 전단강도, 연성능력 및 에너지소산능력이 변화할 가능성이 크다. 이 연구에서는 6개의 철근콘크리트 경사기둥-보 접합부($90^{\circ}$, $67.5^{\circ}$, $45^{\circ}$) 실험을 수행하고 결과를 분석하였다. 실험 결과에 의하면 경사기둥-보 접합부에서 비대칭 파괴가 발생하였으며 수직기둥-보 접합부에 비해서 최대하중과 에너지소산능력이 감소하는 것으로 나타났다. 이것은 경사기둥으로 인해 발생되는 접합부의 상이한 모멘트 분포와 압축력만 받는 수직기둥과 다르게 경사기둥이 압축력뿐 아니라 인장력도 작용하기 때문이다.

• 한국전산구조공학회논문집
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• 제26권3호
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• pp.173-182
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• 2013

최근 진행되고 있는 건축 프로젝트는 기존의 정형적인 구조계획에서 벗어나 점차 복합적이고 다양한 형태를 지향하고 있다. 이와 같은 새로운 건축 트렌드 속에서, 비정형 건축물의 구조 시스템을 효율적으로 현실화하여 골조의 직교성을 해체시키는 기술에 대한 연구의 필요성이 대두되고 있다. 비정형 건축물의 중요한 구조적 특징 중 하나로 경사기둥의 빈번한 적용을 들 수 있다. 경사기둥은 접합된 보에 추가적으로 모멘트와 축력을 전달하므로, 이러한 현상이 골조 및 보-기둥 접합부의 거동에 어떠한 영향을 미치는지를 실험 혹은 해석을 통해 검증할 필요가 있다. 그러나 수직기둥-보 접합부에 비하면 경사기둥-보 접합부에 대한 연구는 현재까지 충분한 연구가 이루어지지 않고 있는 실정이다. 따라서 본 연구에서는 비선형해석 및 유한요소해석을 사용하여 경사기둥을 포함한 보-기둥 접합부의 성능을 평가하였다. 경사기둥을 포함한 철골모멘트 골조의 비선형정적해석을 통하여 골조 전체의 거동을 분석하였고, 경사기둥-보 접합부 모델의 유한요소해석을 통해 좌굴거동 및 취성파단 잠재성을 검토하였다.

• Structural Engineering and Mechanics
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• 제16권4호
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• pp.493-517
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• 2003

Attempts at improving beam-column joint performance has resulted in non-conventional ways of reinforcement such as the use of the crossed inclined bars in the joint area. Despite the wide accumulation of test data, the influence of the crossed inclined bars on the shear strength of the cyclically loaded exterior beam-column joints has not yet been quantified and incorporated into code recommendations. In this study, the investigation of joints has been pursued on two different fronts. In the first approach, the parameters that influence the behaviour of the cyclically loaded beam-column joints are investigated. Several parametric studies are carried out to explore the shear resisting mechanisms of cyclically loaded beam-column joints using an experimental database consisting of a large number of joint tests. In the second approach, the mechanical behaviour of joints is investigated and the equations for the principal tensile strain and the average shear stress are derived from joint mechanics. It is apparent that the predictions of these two approaches agree well with each other. A design equation that predicts the shear strength of the cyclically loaded exterior beam-column joints is proposed. The design equation proposed has three major differences from the previously suggested design equations. First, the influence of the bond conditions on the joint shear strength is considered. Second, the equation takes the influence of the shear transfer mechanisms of the crossed inclined bars into account and, third, the equation is applicable on joints with high concrete cylinder strength. The proposed equation is compared with the predictions of the other design equations. It is apparent that the proposed design equation predicts the joint shear strength accurately and is an improvement on the existing code recommendations.

• Structural Engineering and Mechanics
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• 제18권4호
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• pp.389-410
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• 2004

In this study, theoretical and experimental results are presented which were obtained during an investigation of the influence of the $P-{\Delta}$ effect that was caused by the simultaneous changing of the axial load P of the column and the lateral displacement ${\Delta}$ in the external beam-column joints. The increase or decrease of ${\Delta}$ was simultaneous with the increase or decrease of the axial compression load P and caused an additional influence on the aseismic mechanical properties of the joint. A total of 12 reinforced concrete exterior beam-column subassemblies were examined. A new model, which predicts the beam-column joint ultimate shear strength, was used in order to predict the seismic behaviour of beam-column joints subjected to earthquake-type loading plus variable axial load and $P-{\Delta}$ effect. Test data and analytical research demonstrated that axial load changes and $P-{\Delta}$ effect during an earthquake cause significant deterioration in the earthquake-resistance of these structural elements. It was demonstrated that inclined bars in the joint region were effective for reducing the unfavourable impact of the $P-{\Delta}$ effect and axial load changes in these structural elements.

• 한국강구조학회 논문집
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• 제29권2호
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• pp.181-192
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• 2017

최근 경사단부강판과 고장력 볼트를 이용한 보 이음(Inclined end-plate beam splice) 공법이 개발되었다. 단부강판은 브래킷 단부에 용접되고 연결보는 고장력 볼트를 통해 이음시킨다. 기둥면에는 브래킷이 용접되고, 브래킷과 연결보 단부에 각각 경사단부강판과 고장력 볼트를 이용하여 이음 시킨다. 이 연구에서는 총 6개의 외부 보-기둥 모멘트접합부의 반복가력실험을 수행하였다. 실험변수는 단부강판 상세와 볼트 배열 상세이다. 모든 실험체는 AISC Design Guide 4에 따라 단부강판 및 볼트에 의한 모멘트 저항성능이 보 이음부 요구모멘트보다 크도록 설계되었다. 실험결과, 확장된 단부강판(Extended end-plate)을 사용한 보이음부의 경우 이음부 단부강판의 지레작용 및 볼트의 취성 파단 없이 중앙 보 모멘트가 단부 브래킷으로 효과적으로 전달되었다. 하지만, 보-기둥 접합부의 변형능력은 기둥면 보 플랜지 용접부의 취성파단으로 제한적이었다. 실험결과를 바탕으로, 기울어진 단부강판 이음부를 갖는 보-기둥 모멘트접합부의 내진설계를 위한 개선사항을 제안하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.51-54
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• 2005

Light Guide Plate (LGP) of LCD-BLU(Back Light Unit) is manufactured by forming optical pattern with $5\~100um$ in diameter on the LGP by means of sand blasting or etching method. However, in order to improve the luminance of LCD-LGP, the design of optical pattern has introduced UV inclined-exposure process in this study. This micro-optical pattern, which has asymmetric elliptical column shaped pattern, can change low viewing-angle to high viewing-angle, as well as it contribute to diffusion of light. As a result, this type of micro-optical pattern can introduce the highly luminance. The PR structure obtained in the stage of lithography has asymmetric elliptical column shape and it is processed into a micro-optical pattern. Optical design with this kind of micro-optical pattern, mold fabrication by electroplating and LGP molding with injection molding are under way.

• 한국해양공학회지
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• 제36권4호
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• pp.270-279
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• 2022

In this study, numerical analysis and experiments were performed to analyze the viscous damping effect according to the shape of the chamber skirt of the breakwater-linked inclined oscillating water column wave energy converter. Experiments were conducted using a two-dimensional mini wave tank and verified by comparing the results of a computational fluid dynamics numerical analysis. Pointed and rounded skirts were modeled to compare the effect of viscous damping when incident waves enter the chamber, and the difference in the displacement of the water surface in the chamber was compared according to the wave period for the two skirt shapes. The wave elevation in the chamber in the rounded-skirt condition was larger than the pointed-skirt condition in all wave periods, which was approximately 47% greater at 0.9 s of the incident wave period. Therefore, extracting the maximum energy through the optimal orifice is possible while minimizing the energy attenuation in the rounded-skirt condition.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1989년도 가을 학술발표회 논문집
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• pp.77-82
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• 1989

In this paper an experimental approach of the relocation plastic hinging zones of nine reinforced concrete exterior beam-column subassemblages under cyclic loads was tried. The main parameters of the testing program were location of the plastic hinge, difference of the special reinforcement, inclined or intermediate layers of longitudinal reinforcement, applied maximum shear stress. The conclusions presented herein are based on the limited texts conducted. Inclined or intermediate layers of longitudinal reinforcement and extra top and bottom steel in the beam over a specific legnth can be used to move the beam plastic hinging zone away from the column face. But, for the use of intermediate layers of longitudinal reinforcement, sheat reinforcement detail need further investigation.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2009년도 정기 학술대회
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• pp.119-124
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• 2009

This paper proposes a tuned liquid column sloshing damper(TLCSD) and presents experimental results to evaluate its control performance. The proposed damper acts as a tuned liquid column damper(TLCD) and a tuned liquid damper(TLD), respectively, in both principal axes of building structures. Shaking table test was performed to grasp its dynamic characteristics. Testing results showed that under inclined incident excitations, a TLCSD used in this study have dynamic characteristics coupled by both TLCD and TLD.

• 대한치과교정학회지
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• 제22권1호
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• pp.169-177
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• 1992

This investigation was carried out in order to find out changes in head postures and in craniofacial morphology, in relation to the inclination of cervical column. For this study 85 subjects, consisting 39 males and 49 females, between the ages of 7 to 24 years old were chosen, and following results were observed after analysing the correlation coefficients between each structures. 1. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and the inclination of anterior cranial base (SN/VER) 2. No definite relationships were observed between the inclination of mandibular ramus (RL/HOR) and the inclination of mandibular inclination (MLP/VER). 3. In subjects with anteriorly inclined cervical column, increase in mandibular plane inclinations (ML/VER) were observed. 4. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and changes in palatal plane (NL/VER).