• 해양환경안전학회지
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• 제12권1호
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• pp.67-74
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• 2006

선체를 구성하는 판부재는 일반적으로 면내하중과 횡하중의 조합하중이 작용하게 된다. 면내하중으로서는 주로 전체적인 선체거더의 휨과 비틀림에 의한 압축하중 및 전단하중이 있다. 횡하중은 수압과 화물압력에 의해서 작용하게 된다. 이러한 하중의 요소들은 항상 동시에 작용하는 것은 아니지만 한 개 이상의 하중이 존재하고 상호작용하게 된다. 그러므로, 좀 더 합리적이고 안정적인 선박구조의 설계를 위해서는 이러한 조합하중이 선체판에 작용할 경우에 발생하게 되는 좌굴 및 최종강도거동의 상호관계를 좀 더 자세히 분석할 필요가 있다. 실제로 선체판은 슬래밍과 팬팅과 같은 충격하중을 제외하고는 상대적으로 작은 수압이 작용하게 된다. 본 연구에서는 조합하중을 받는 선체판부재의 거동에 있어서 최종한계상태 설계법에 기반을 둔 탄소성대변형 유한요소해석을 수행하였다. 본 연구에서는 압축하중과 횡하중이 판부재에 작용하였을 경우 횡하중의 크기에 따른 2차좌굴 거동의 영향을 탄소성대변형 유한요소해석(ANSYS)으로 분석하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.983-999
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• 2014

The structural design of the ships includes two main issues which should be checked carefully, namely the extreme structural response (yielding & buckling) and the fatigue structural response. Even if the corresponding failure modes are fundamentally different, the overall methodologies for their evaluation have many common points. Both issues require application of two main steps: deterministic calculations of hydro-structure interactions for given operating conditions on one side and the statistical post-processing in order to take into account the lifetime operational profile, on the other side. In the case of ultra large ships such as the container ships and in addition to the classical quasi-static type of structural responses the hydroelastic structural response becomes important. This is due to several reasons among which the following are the most important: the increase of the flexibility due to their large dimensions (Lpp close to 400 m) which leads to the lower structural natural frequencies, very large operational speed (> 20 knots) and large bow flare (increased slamming loads). The correct modeling of the hydroelastic ship structural response, and its inclusion into the overall design procedure, is significantly more complex than the evaluation of the quasi static structural response. The present paper gives an overview of the different tools and methods which are used in nowadays practice.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.113-119
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• 2004

A steel plated is typically composed of plate panels. The overall failure of the structure is certainly affected and can be governed by the bulking and plastic collapse of these individual members In the ultimate limit state design. therefore. a primary task is to accurately calculate the budding and plastic collapse strength of such structural members. Structural elements making up steel palated structures do not work separately. resulting in high degree of redundancy and complexity in contrast to those of steel framed structures. To enable the behavior of such structures to be analyzed, simplifications or idealizations must essentially be made considering the accuracy need and degree of complexity of the analysis to be used Generally the more complex the analysis the greater is the accuracy that may be obtained. The aim of this study is the investigation of the effect of the tripping behaviour including section characteristic for a plate under uniaxial compression.

• 전산구조공학
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• 제8권1호
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• pp.85-94
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• 1995

수압을 받는 원통형 쉘의 몸체설계는 구조물에 외압이 작용할 때 발생하는 최대 응력과 변형 및 좌굴을 해석하여, 주어진 한계를 견딜 수 있는 쉘의 두께를 구해야 한다. 중앙 평형부 몸체의 두께를 설계변수로 선정하여 형상 최적화법으로서 원통형 쉘의 치수를 설계하는 방법을 제안하였다. 민감도 해석은 직접 미분법을 사용하여 유도하였으며, 비선형 계획법으로 최대 응력과 변형 및 좌굴 제한식 등을 만족하는 최적설계를 수행하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.181-188
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• 2000

This paper describes the energy absorption of a square tube under axi compression by using the finite element method. The overall deformations and lo buckling modes of tube was discussed by "plastic hinge concep Force-displacement function was plotted to show various state that depended or time. Also, mean crush load was expressed as a type of section geometry a material property using dimensional analysis. To verify the energy absorption and the effects of dimensions, The standards Wt used as related density and specific energy, mean crushing load and the resL were discussed by the relation between crush load and deformation, the relati between related density and specific energy, the relation between crush load a mean crush load, the relation between mean crush load and specific energy.ergy.

• Computers and Concrete
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• 제2권2호
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• pp.147-164
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• 2005

This paper summarizes an experimental study on the seismic behavior of lower stories of a mid-rise reinforced concrete frame building. Two reinforced concrete frames with two stories and one span were tested and each frame represents lower two stories of an 11-story RC frame building. Both frames were designed in accordance with Japanese design guidelines and were identical except in the variation of axial force. The tests demonstrated that the overall load-displacement relations of the two frames were nearly the same and the first-story column shear was closely related to the column axial load. The columns and beams elongated during both of the tests, with the second-floor beam elongation exceeding 1.5% of the beam clear span length. The frame with higher axial loads developed more cracks that the frame under moderate axial load.

• Journal of Mechanical Science and Technology
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• 제18권5호
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• pp.762-769
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• 2004

An analytical approach is presented to investigate the deformation characteristics of billets in a continuous billet mill using power driven horizontal stands and idle vertical stands. The analysis is validated by comparison to the experimental results in a previously published work. The analytical results have shown that, apart from the problems of slip and buckling of billet, there are some shortcomings involved in this method. Compared to conventional rolling with all driven stands, the roll load for idle vertical stands and the rolling torque for horizontal stands are almost doubled. The billet is severely stressed within the roll-bite of idle vertical stands and the overall rolling power has increased by one third of that for conventional rolling. Theseshortcomings impair the feasibility of industrial application of idle vertical stand rolling method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.109-115
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• 2003

This study intends to provide an optimum design of flexible matrix composite driveshafts using a genetic algorithm. An objective function is defined as a combination of shaft flexibility, whirling stability and torsional buckling and the design variables are selected as ply angles and the shaft thickness. Results show that the genetic algorithm can successfully find an optimum solution at which the overall performance of the FMC shafts is significantly enhanced

• Steel and Composite Structures
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• 제12권2호
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• pp.93-115
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• 2012

This paper presents a numerical investigation of the mechanical behaviour of extended end - plate steel connections including comparison with full size experiments. Contact and friction laws have been taken into account with nonlinear, three dimensional finite element analysis. Material and geometric nonlinearities have been implemented to the model, as well. Results are then compared with experimental tests conducted at the Jordan University of Science and Technology. According to the most significant observation of the analysis, a separation of the column flange from the extended end - plate occurs. Other important structural parameters of the connection, like the impact of some column stiffeners on the overall response, local buckling of the column and friction of the beam to column interface, have been examined as well.

• Steel and Composite Structures
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• 제50권5호
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• pp.531-548
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• 2024

This paper presents an experimental investigation into the progressive collapse behavior of composite steel-concrete frames under various column removal scenarios. This study involves testing two two-bay, two-story composite frames featuring CFST columns and profiled steel decking composite slabs. Two removal scenarios, involving the corner column and middle column, are examined. The paper reports on the overall and local failure modes, vertical force-deformation responses, and strain development observed during testing. Findings indicate that structural failure initiates due to fracture and local buckling of the steel beam. Moreover, the collapse resistance and ductility of the middle column removal scenario surpass those of the corner column removal scenario. Subsequent numerical analysis reveals the significant contribution of the composite slab to collapse resistance and capacity. Additionally, it is found that horizontal boundary conditions notably influence the collapse resistance in the middle column removal scenario only. Finally, the paper proposes a simplified calculation method for collapse resistance, which yields satisfactory predictions.