• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.232-233
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• 2004

강구조물 제작 시 용접프로세스에 의해 용접부 근방에 불균일한 온도분포가 발생하여 용접변형이 발생된다. 이러한 용접변형은 좌굴강도와 피로강도를 저하시킬 뿐 아니라 구조물의 크기와 형상을 변화시켜 이를 교정하거나 수정하기 위해 추가작업을 실시해야함으로 생산성을 저하시키는 주요한 요인이 되고 있다. (중략)

• 대한기계학회논문집
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• 제17권7호
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• pp.1686-1699
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• 1993

In this paper, the thermal buckling of thick composite angle-ply laminates subject to uniform temperature distribution is studied. For the plates of 4-edges simply supported condition and those of 4-edges clamped condition, the critical buckling temperatue is derived, using tile finite element method based on the shear deformation theory. The effects of lamination angle, layer number, laminate thickness, plate aspect ratio and boundary constraints upon the critical buckling temperature are presented.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.207-212
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• 2002

The actual buckling of the railroad track structure is suspected to be a complex interaction between the vertical, lateral and torsional modes. To make the analysis tractable, however, most studies restrict themselves to either the vertical or the horizontal plane. Based on a comprehensive and realistic three-dimensional track model developed in the previous study, three dimensional buckling analysis of CWR track subjected to temperature load was performed. Using the study on buckling temperature and mode, sensitivity of track components such as tie spacing, ballast resistance, stiffness of pad-fastening system and rail size were investigated.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.654-659
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• 2002

Continuous Welded rail(C.W.R.) tracks has many advantages over the conventional jointed rail track. Due to the elimination of rail joints for thermal expantion, however it many cause the track to be suddenly bucklled by thermal loads. The present study investigates the influences of Pad-fastner on the Thermal buckling behavior of C.W.R. Parametric studies are performed to evaluate the effects of the individual parameters on the upper and lower critical bucklig temperature.

• 한국철도학회논문집
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• 제13권2호
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• pp.179-185
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• 2010

장대레일 좌굴과 파단에 대한 안정성을 확보하고 효율적인 유지관리를 위해서는 레일온도의 특징을 파악하는 것이 매우 중요하다. 최근 들어, 기후변화에 의해 여름철 최고 대기온도는 상승하고 겨울철 최저 대기온도는 점점 하강하고 있다. 이러한 현상은 연간 레일온도의 변화량에 영향을 미치게 되고 설정온도와 관리온도의 변화를 일으킬 수 있다. 본 연구에서는 기후 및 온도 측정시스템을 구축하여 기후요소를 포함한 레일온도를 실측하였다. 실측자료의 심층적인 분석을 통하여, 기존 레일온도 추정식은 특정한 조건(기후요소들의 특정 조합) 에서만 적용이 가능함을 알 수 있었다. 현장의 실제 기후요소를 고려한 레일온도를 확률론적 접근으로 예측하는 것이 더욱 합리적일 것이다.

• 대한기계학회논문집
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• 제12권5호
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• pp.952-958
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• 1988

본 연구에서는 폭방향 불균일 냉각에 따른 열응력이 판변형 및 잔류응력의 주 요원인이라는 고려하에 냉각중에 압연판의 온도분포 및 열응력을 예측할 수 있는 수치 해석 모델을 구성하였다. 온도와 응력 계산에 상변태 현상을 고려하였으며, 판변형 은 압축성분 열응력에 의한 좌굴현상으로 고려하여 해석하였다.

• 대한기계학회논문집A
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• 제30권7호
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• pp.809-815
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• 2006

The temperature and loading-rate dependence on the mechanical behavior of single-walled carbon nanotubes under axial compression and torsion is examined with classical molecular dynamics simulation. The critical buckling is found to depend on the temperature and loading-rate. The yielding under torsion is also found to depend on the temperature and loading-rate. But it is shown that the compression and torsional stiffness are independent of the varied temperatures and loading-rates.

• 한국강구조학회 논문집
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• 제22권6호
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• pp.523-532
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• 2010

콘크리트가 충전된 각형강관기둥(이하, 각형 CFT기둥)은 높은 내화성능과 하중저항능력을 보유하고 있지만, CFT기둥의 외부에 내화피복을 함으로써 기둥의 내화성능을 향상시킬 필요가 있다. 본 연구는 내화 피복된 각형 CFT기둥의 온도분포에 대한 실험결과이다. 실험을 위하여 특수 제작된 전기로를 이용하여 축소모형 시험체의 재하가열실험을 수행하였다. 축하중을 받는 내화 피복된 각형 CFT기둥의 온도 분포 특성을 파악하기 위하여 내화피복의 종류와 두께, 강관의 두께 및 가열시간 등을 변수로 설정하였다. 실험결과 전기로의 온도에 따른 시험체별 온도분포와 콘크리트와 강재의 온도분포 특성을 파악하였다. 또한 시험체의 온도변화에 따른 축변위와 국부좌굴 등의 거동을 파악하였다.

• 한국철도학회논문집
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• 제3권1호
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• pp.19-26
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• 2000

The rail temperature is important to preserve the joint gap for standard length of rail and to determine the installation temperature which has direct influence on the rail buckling and failure in welded part for continuous welded rail(CWR), Therefore, we have measured and investigated various characteristics of rail temperature for each kind of rail. As the results of this, the correlation between the atmosphere temperature and the rail temperature which is commonly used by Korean Railway should be reconsidered. Also, the daily highest '||'&'||' lowest rail temperature was occurred when each temperature is higher and when it's lower. For the light rail, the rail temperature by the sun-light increases quickly and decreases late. But the time where the highest temperature is attained is same. There are some differences between the shade and sunny place about 3.0∼4.0$\^{C}$. The temperature of rail web is almost close to the conversion rail temperature for rail expansion. The wind of 1 m/s has an influence on the rail temperature around 5$\^{C}$.

• 대한조선학회논문집
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• 제49권3호
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• pp.222-226
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• 2012

When ship blocks are erected or pre-erected, most blocks will be at outdoors where they are not protected from weather and exposed to ray of the sun. A deck plate compared to those in radiation heat transfer from the sun will have higher temperature than it of ambient air, and will expand more than lower laying structures whose temperatures are similar with air. But deck plates and under-structures are connected, so the deck plate will be under out-of-plane deformation rather than expand in length. In this study, we considered the temperature difference between air and plate as a major parameter of out-of-plane deformation, and analyzed how much additional deformation would take place. In addition, when a deformation could take place was also analyzed based on the initial deformed shape of deck plate. Because the accuracy inspections of deck plate will be done during daytime, conventional accuracy check results on sunny day could make us feel unfair. Thus resonable datum about momentary additional out-of-plane deformation due to environmental effects have been determined. The real deformation values can be specified even under enlarged deformations by radiation-expansion.