• 대한토목학회논문집
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• 제10권3호
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• pp.67-75
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• 1990

보존력 및 비보존력을 받는 평면뼈대 구조물의 동적 후좌굴거동을 추적하기 위하여 비보존력의 방향변화를 고려할 수 있는 기하적인 비선형 유한 요소해석 방법을 제시하였다. 보존력계와 비보존력계에 대하여 내적 및 외적감쇠효과를 고려하는 비선형 패트릭스 운동 방정식을 유도하고 Newmark 방법을 사용하여 수치적으로 직접 적분하였다. Post-divergence 및 Post-flutter 현상들응 보여주는 해석예제들을 통하여 내적 및 외적감쇠하중이 이러한 비선형 동적 후좌굴거동들에 미치는 영향들을 조사하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1068-1073
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• 2003

Method for contact failure mitigation is studied in this paper. The focus is laid on the contact shape that eventually influences the internal stresses. Contact mechanics is consulted within the frame of plane problem. Hertzian contact, rounded punch and uniform traction profiles are considered. Frictional as well as frictionless contact is also considered. As results, the higher traction profile induced by the rounded punch reveals the greatest among the considered shapes. Therefore, it is suggested to increase the edge radius as large as possible if a contact body of punch shape needs to be designed. It is also found that uniform traction cannot always provide the solution of contact failure mitigation.

• 한국구조물진단유지관리공학회 논문집
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• 제7권1호
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• pp.131-138
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• 2003

This paper presents an analytical prediction of the prestress losses of prestressed concrete bridges. In this study a numerical procedure and computer program is developed to analyze the behavior of prestressed concrete bridges considering the time-dependent properties of material. It accounts for the aging, creep and shrinkage of concrete and the stress relaxation of prestressed steel. The structural model uses two dimensional plane frame elements with three nodal degree of freedom and is analyzed based on the finite element method. Member cross section can consist of concrete, reinforcement and prestressing steel. Two different set of equations for the prediction of time-dependent material properties of concrete are presented, which are ACI, CEB-FIP. The proposed numerical method for the prestress losses of prestressed concrete bridges is verified by comparison with reliable experimental results.

• 한국측량학회지
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• 제3권2호
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• pp.18-31
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• 1985

본 연구는 FEM에 의한 3 변측양의 조정을 해석하는데 그 목적이 있으며, FEM은 대상물의 예위 및 변동의 문제를 해석하는 수치해석이다. 본 연구에서는 평면 3 각망과 평면구조물과의 형상과 해석이 비슷하기 때문에 FEM의 기법을 3변측양조정에 이용하였다. 따라서 본 연구에서는 3 변측양조정에 FEM과 조건방정식방법을 적용하여 그들의 정밀도와 특성을 고찰하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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• pp.53-60
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• 1998

Efficiency of design process for large scale structures highly depends on the development of efficient structural analysis and structural response control algorithms because a successful design involves a number of structural analysis based on iterative structural response control process. In this paper, distributed structural analysis model on multiple personal computers connected by ethernet network is presented. To reduce communication cost required in the process of analysis, substructuring techniques are adopted to evenly distribute computational loads on each processor. With its applications on structural analysis of plane frame structures, performance of the proposed computational model are presented in detail.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.557-564
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• 2002

One of the primary factors like plate structure In ship is redundancy structure that is comparable with ocean structure and frame structure. The more component material becomes buckling collapsed locally the less structure stiffness becomes accordingly. As a result, by increasing the load distribution of any other subsidiary structure continually component member collapses, therefore the structure could be in danger of collapse. So, in order to interpret this phenomenon precisely, the study on boundary condition of the ship's Plate and post-buckling analysis must be considered. In this study, the rectangular plate is compressed by the in-plane load. Buckling ＆ Ultimate strength characteristics we applied to be the elasto-plasticity large deformation by F.E.M. On this basis, elasto-plasticity of the plain plate are investigated. This study proved elasto-plasticity behaviour of tile ship's plate In accordance with boundary condition based on the series analysis In case of the compressive load operation.

• 전산구조공학
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• 제9권3호
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• pp.187-197
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• 1996

Explicit 직접적분법 알고리듬을 사용하여 Euler기둥의 동적 좌굴거동을 해석할 수 있는 수치해석법을 제시하였다. 평면뼈대 유한요소를 기하학적 비선형 거동과 전체좌굴의 영향을 고려할 수 있도록 보의 대변위 이론으로부터 유도하였고, central difference method를 바탕으로 해석 알고리듬을 개발하였다. 다양한 형상, 크기, 재하시간을 갖는 충격하중에 대하여 Euler기둥의 동적좌굴거동과 고유치 문제를 해석하였다. 수치해석 예제를 통하여 본 연구의 결과를 검증하였다.

• 플랜트 저널
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• 제5권4호
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• pp.80-85
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• 2009

LNG stevedoring plant offshore pipelines requires human power and the longest construction period in constructing LNG storing terminal and influences on the success of the project absolutely. In this paper, the constructing procedures of LNG stevedoring plant offshore pipeline was established. Establishment of constructing procedures of LNG stevedoring plant offshore pipeline includes procurement of main equipments, iron frame and pipelines. To predict any expectable problems, that may occur by the stage of construction the application to the field works with a base of theoretical and practical contents for the constructing procedures of LNG stevedoring plant offshore pipelines can be established.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.401-407
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• 1996

A 2-bay 2-story moment-resisting reinforced concrete plane frame with seismic detail was designed. One 1/2.5-scale and one 1/10th model subassemblages were manufactured accoring to the required similitude law. Then the reversed load tests under the displacement control were performed statically to these subassemblages. The results of these tests were compared regarding to the similitude in the characteristics of structural behaviors such as strength., stiffness, energy dissipation, failure modes and local deformations. Based on these results, the following conclussions were drawn : (1) The strength of 1/10 model was very similar to that of 1/2.5 specimen. (2) The initial stiffness of 1/10 model appers to be approximately 2/3 of that of 1/2.5 specimen. (3) 1/10 model has therefore smaller energy dissipation capacity than 1/2.5 specimen. (4) Inelastic excursion mechanisms of 1/2.5 specimen and 1/10 model apper to be a little different.

• 한국해양공학회지
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• 제2권2호
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• pp.71-77
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• 1988

For the collapse of structures due to the variable repeated load, two types of collapse mechanisms, i.e., incremental collapse and alternating plasticity, exist. Under the similar variable repeated loading conditions there exists shakedown state in the structures. In shakedown state, the number of plastic hinges are not increased and all further loading will be resulted in the elastic moment changes. Namely, under the shakedown state, structures do not collapse. In this investigation, shakedown analysis are performed by composing new computer programs. Basic theories employed to compose the programs are as follows. 1. Newton-Raphson methods are added to the existing matrix method for the plastic analysis. 2. An effort to construct the stiffness of axial and bending springs attached at both ends of the member has been made. By using the programs developed, it is possible to anticipate the collapse mechanisms (Incremental collapse, alternating plasticity). Lastly for the verification of performance of the program, demonstration examples have been solved and the results are compared with other sources.