• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.37-40
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• 2008

The study is an experimental test on full-scale flat plate slab-column interior connection. The punching shear on the flat plate slab-column connection can bring about the reason of the brittle punching shear failure which may result of collapsing the whole structure. From the development of residential flat plate system, the shear reinforcement is developed for preventing the punching shear. For making sure of the punching shear capacity, developed for shear reinforcement in slab-column connection, the structural test is performed. The dimension of the slabs was 2620*2725*180mm with square column (600*800mm). The slabs were tested up to failure monotonic vertical shear forces. The presences of S/S bar and wire mesh substantially increased the punching shear capacity and the ductility of the slab-column connections.

• 한국전산구조공학회논문집
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• 제25권3호
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• pp.259-266
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• 2012

본 논문에서는 벽식 구조시스템의 일부 전단벽을 제거하여 공간의 가변성을 높인 무량복합 구조시스템의 내진성능을 ATC-63에 제시되어 있는 절차에 따라 파악하였으며, 동일한 규모의 벽식 구조시스템의 내진성능과 비교하였다. 해석모델로 12층 무량복합 및 벽식 구조시스템을 KBC 2009에 따라 설계하고 비선형 정적 및 비선형 증분 동적해석(IDA)을 수행하여 지진응답 및 붕괴거동을 파악하였다. 무량복합 시스템은 벽식 구조시스템 보다 적은 양의 콘크리트 물량으로 설계되었으며, 동일한 지진하중에 대하여 좀 더 큰 변위응답을 보이는 것으로 나타났다. IDA 해석결과 얻어진 붕괴 여유비(CMR)는 ATC-63에 제시된 한계상태를 만족하여 설계지진하중에 대하여 충분한 내진성능을 보유한 것으로 나타났다.

• Structural Engineering and Mechanics
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• 제21권4호
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• pp.451-468
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• 2005

Effective beam width models are commonly used to obtain the lateral stiffness of flat plate structures. In these models, an effective beam width is defined as the width when the flexural stiffness of the beam element equals the slab stiffness. In this present study, a method to obtain effective beam widths that considers the effects of connection geometry and slab cracking is analytically proposed. The rectangularity of the vertical member for the connection geometry and the combined effects of creep and shrinkage for the slab cracking are considered. The results from the proposed method are compared with experimental results from a test structure having nine slab-column connections.

• 한국소음진동공학회논문집
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• 제24권8호
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• pp.651-658
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• 2014

Notification 2013-611 of MOLIT has come into effect. It relates primarily to new standard impact source. In this study, an in-depth experimental analysis of the difference between a bang machine and an impact ball was performed via field testing of shear wall and flat plate structure at 51 sites. This paper focuses on the difference in single number quantities between a bang machine and an impact ball. At wall thicknesses of 180 and 210 mm in shear wall structure, the single number quantities exhibited differences of 3.1 and 4.5 dB, respectively, and at thicknesses exceeding 250 mm in flat plate structure, the difference was constant at 4.6 dB. With regard to flat plate structures, the single-index difference increased up to 11 dB as the thickness of the floor slab increased. In general, the highest level of contribution for the bang machine was 63 Hz, irrespective of thickness determining bandwidth. The highest level for the impact ball were 63 Hz and 125 Hz. In future research, when reviewing additional field performance measurement data, it will be necessary to consider a detailed examination instead of the current method of uniformly adding 3 dB for all thicknesses and types of structures.

• 콘크리트학회논문집
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• 제15권6호
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• pp.856-865
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• 2003

성능기초설계를 위한 기존의 설계방법 및 지침은 플랫 플레이트구조의 내진성능을 정확히 예측하지 못한다. 이전의 연구에서는 슬래브-기둥 접합부에 대하여 비선형 유한요소해석를 이용한 변수연구를 수행하였으며, 해석결과 및 기존실험결과에 근거하여 플랫 플레이트 접합부의 휨모멘트 강도와 최대변형능력을 추정할 수 있는 설계방법을 개발하였다. 본 연구에서는 선행연구결과와 비선형 해석결과에 근거하여 플랫 플레이트구조의 일반화된 모멘트-변형각의 관계를 제안하였으며, 기존 실험결과와의 비교를 통해 검증하였다. 또한 풍하중을 받는 플랫 플레이트구조의 변형을 쉽게 구할 수 있도록 0.2% 층간변위비에 대한 슬래브의 강성보정계수를 제안하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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• pp.258-265
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• 1998

Application of the flat shell element with drilling D.O.F to linear buckling analysis of thin-walled structures is presented in this paper. The shell element has been developed basically by combining a membrane element with drilling D.O.F. and Mindlin plate bending element. Thus, the shell element possesses six degrees-of-freedom per node which, in addition to improvement of the element behavior, permits an easy connection to other six degrees-of-freedom per node elements(CLS, Choi and Lee, 1995). Accordingly, structures like folded plate and stiffened shell structure, for which it is hard to find the analytical solutions, can be analyzed using these developed flat shell elements. In this paper, linear buckling analysis of thin-walled structures like folded plate structures using the shell elements(CLS) with drilling D.O.F. to be formulated and then fulfilled. Subsequently, buckling modes and the critical loads can be output. Finally. finite element solutions for linear buckling analysis of folded plate structures are compared with available analytic solutions and other researcher's results.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.871-874
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• 2008

KBC 2005를 처음 적용할 때 많은 구조엔지니어들이 무량판 구조에 대한 횡력저항시스템 선정과이에 따른 상세적용에 많은 어려움이 있었다. 현재 KBC 2005에 대한 개정작업이 진행중에 있다. 이러한 시점에서 최근 개정 중인 건축구조기준의 개정안을 토대로 향후 개정안에 적용가능한 구조시스템을 미리 살펴볼 필요가 있다. KBC 2008(안)의 경우 내진설계범주에 따른 시스템의 높이제한, 특수전단벽과 같은 특수상세, 전단벽-골조 상호작용시스템과 같은 새로운 시스템의 도입으로 구조설계자가 현행 기준보다 시스템에 대하여 휠씬 더 다양한 선택이 가능할 것으로 판단된다.

• 한국소음진동공학회논문집
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• 제17권2호
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• pp.168-176
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• 2007

The mixture sound speed in bubbly fluids is highly dispersive due to differences of the density and compressibility between bubbles and fluids. The dispersion range in bubbly fluids expands to a higher frequency than the resonance frequency of an air bubble. A theoretical model was developed to compute the reduction of radiation noise that is generated by a force applied on an infinite flat plate using a bubble layer as a compliant baffle. For evaluating the effectiveness of a bubble layer in reducing the structure-borne noise of an infinite elastic plate, the noise reduction levels for various parameters such as the thickness of bubble layers, the volume fractions and the distribution types of bubbly fluids are calculated numerically. The noise reduction effect of an air bubble layer on an infinite flat plate is considerable level and similar to the tendency of dispersion of bubbly fluids. It is recommended that the thickness of a bubble layer should be increased with keeping an appropriate volume fraction of an air bubble for the most effective reduction of the radiation noise.

• 대한기계학회논문집B
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• 제22권4호
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• pp.417-427
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• 1998

The effect of secondary flow on the heat transfer of a turbulent wake generated by a flat plate was experimentally investigated. The secondary flow was induced in a curved duct in which the flat plate wake generator was installed. All three components of turbulent heat flux were measured in the plane containing the mean radius of curvature of the curved duct. The results showed that mean temperature profiles deviate from the similarity of the straight wake because of the cold fluid transported from the free-stream. The half-width of the mean temperature profile increased rapidly by upwash motion of the secondary flow. The changes to turbulence structure caused by the secondary flow show more pronounced effect on heat transport than on momentum transport. This is because the response to the variation of flow conditions is delayed in temperature field. Negative production of the turbulent heat flux is observed in the inner wake region. From the conditional averaging, it has been found that the negative production of the turbulent heat flux is generated due to a mixing process between the hot and low momentum eddies occupied in the inner wake region and the cold and high momentum eddies in the potential region.

• 대한기계학회논문집B
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• 제25권11호
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• pp.1476-1482
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• 2001

Turbulent boundary layer over a flat plate was disturbed by installing an elliptic cylinder with an axis ratio of AR=2. For comparison, the same experiment was carried out for a circular cylinder having the same vertical height. The surface pressure and the heat transfer coefficient on the flat plate were measured with varying the gap distance between the elliptic cylinder and the flat plate. The mean velocity and the turbulent intensity profile of the streamwise velocity component were measured using a hot-wire anemometry. As a result, the flow structure and the local heat transfer rate were modified by the interaction between the cylinder wake and the turbulent boundary layer as a function of the critical gap ratio where the regular vortices start to shed. For the elliptic cylinder, the critical gap ratio is increased and the surface pressure on the flat plate is recovered rapidly at downstream location, compared with the equivalent circular cylinder. The maximum heat transfer rate occurs at the gap ratio of G/B = 0.5, where the flow interaction between the lower shear layer of the cylinder wake and the turbulent boundary layer is strong.