• 한국구조물진단유지관리공학회 논문집
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• 제13권1호통권53호
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• pp.115-124
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• 2009

본 연구에서는 구조물에 발생하는 변상 진전 특성을 수치 해석적으로 평가할 수 있는 기법을 새롭게 개발하기 위한 연구를 수행한 것이다. 이를 위해서, 변상발생 메커니즘을 토대로 하여, 인장균열 발생 후, 휨압축에 의한 압축손상까지를 해석에 반영하였다. 특히 인장균열이 발생하고나서 압축손상이 발생하기까지의 해석 단계를 위해서는, 등가소성힌지길이 개념을 새롭게 도입하여, 균열의 진전을 해석하게 된다. 등가소성힌지 길이개념을 도입함으로써, 균열발생단면에 대한 단면력, 즉, 축력과 모멘트를 균열폭과 관계지어 균열폭의 확장을 추적해 나가게 된다.

• 한국전산구조공학회논문집
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• 제26권4호
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• pp.293-300
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• 2013

본 논문에서는 앵커볼트의 체결력을 고려한 유한요소 모델을 제안함으로써 앵커볼트로 연결된 부재의 해석적 평가방법을 제안하였다. LS-DYNA를 사용한 유한요소 모델링은 복잡한 3차원 상세모델보다는 단순화된 앵커모델들을 적용함으로써 해석 효율성을 고려하였다. 앵커볼트는 Beam 혹은 Solid 요소로 토크 조임에 따른 앵커볼트 긴장상태를 반영하였고, 토크 조임에 따른 체결력을 고려하기 위해 너트면에 압축력을 도입하거나 너트를 Shell 혹은 Solid로 고려하여 작용 토크값으로 산정되는 체결력과 등가의 하중을 도입하였다. 외력 작용 시 체결력과 마찰력에 의한 앵커볼트의 하중전달은 nodal rigid 혹은 contact 조건으로 고려하였다. 체결력을 고려한 세 종류의 앵커모델을 적용한 해석결과, Model I과 Model III는 볼트 축력과 전단력이 매우 유사한 값으로 계산되었고, Model II의 경우, 볼트 축력과 전단력이 다소 과소평가되는 것으로 나타났다. Model I은 다른 두 모델에 비해 수치해석적으로 효율적인 것으로 분석되었다.

• Structural Engineering and Mechanics
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• 제45권3호
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• pp.277-309
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• 2013

Beam-to-column connections behaviour plays an important role in the analysis and design of steel and precast concrete structures. The paper presents a computer-based method for geometrically nonlinear frames with semi-rigid beam-to-column connections. The analytical procedure employs modified stability functions to model the effect of axial force on the stiffness of members. The member modified stiffness matrix, and the modified fixed end forces for various loads were found. The linear and nonlinear analyses were applied for two planar steel structures. The method is readily implemented on a computer using matrix structural analysis techniques and is applicable for the efficient nonlinear analysis of frameworks.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1998년도 춘계 학술논문발표회 논문집
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• pp.221-226
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• 1998

In this thesis, the safety assessment method of tile adversiting pillar tower on the penthouse were studied. From the structural analysis results of the adversiting pillar tower, the bending stress, the shearing stress and the axial stress were calculated, and these member forces were applied to the safety assessment of the adversiting pillar tower and the penthouse, respectively.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1998년도 추계 학술논문발표회 논문집
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• pp.147-152
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• 1998

In this thesis, the structural safety evaluation of a building with adversiting pillar tower were studied. From the structural analysis results of a building with adversiting pillar tower, the bending stress, the shearing stress and the axial stress were calculated, and these member forces were applied to the structural safety evaluation of a building with adversiting pillar tower.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.272-277
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• 2003

In order to predict vibration during end-milling process, the cutting dynamics was modelled by using neural network and combined with structural dynamics by considering dynamic cutting states. Specific cutting constants of the cutting dynamics model were obtained by averaging cutting forces and tool diameter, cutting speed, feed, axial depth radial depth were considered as machining factors. Cutting farces by test and by neural network simulation were compared and the vibration during end-milling was simulated.

• Ocean Systems Engineering
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• 제3권2호
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• pp.123-136
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• 2013

This study is devoted to the optimal design of compressed bars under axial compressive forces and exposed to a corrosive environment. The initial volume of the structure is taken as an optimality parameter. Gutman - Zainullin's exponential stress corrosion model is adopted for analysis. Analytical and numerical results are derived for optimal variation of the cross-sectional area of the bar along its axis.

• 한국세라믹학회지
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• 제49권1호
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• pp.29-36
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• 2012

In many applications of functional oxides originally homogeneous materials are exposed to gradients in the chemical potential of oxygen. Prominent examples are solid oxide fuel cells (SOFCs) or oxygen permeation membranes (OPMs). Other thermodynamic potential gradients are gradients of electrical potential, temperature or uni-axial pressure. The applied gradients act as generalized thermodynamic forces and induce directed fluxes of the mobile components. These fluxes may lead to three basic degradation phenomena of the materials, which are kinetic demixing, kinetic decomposition, and morphological instabilities.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.53-58
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• 1992

This research is related to the experimental investigation of the inelastic behavior of R/C columns with high strength concrete. A total of eight specimens have been tested with different span ratios, steel reinforcements and load applications. Through tests bending moments were applied incrementally while axial forces being kept constantly at 80 tons. Careful observation were given to initial crack formation, crack patterns and propagation paths. Comparative studies have been made on the load carrying capacity for R/C columns with high strength concrete versus normal strength concrete.

• Ocean Systems Engineering
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• 제5권1호
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• pp.21-30
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• 2015

This study is devoted to the optimal design of compressed bars under axial tensile or compressive forces and exposed to a corrosive environment. Dolinskii's linear stress corrosion model is adopted for analysis. Analytical and numerical results are derived for optimal variation of the cross-sectional area of the bar along its axis.