• 해양환경안전학회지
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• 제21권4호
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• pp.449-456
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• 2015

본 연구에서는 다양한 감쇠판을 원통형 부유체에 부착하고 수치 시뮬레이션을 통해 원통형 부유체의 heave RAO 및 고유주기의 변화를 고찰하였다. 먼저 감쇠판을 부착하지 않은 원통형 부유체의 heave RAO 및 고유주기를 파악하였고, 원통형 부유체에 부착한 감쇠판의 크기와 형상을 바꿔가며 각 경우에 대한 heave RAO 및 고유주기를 평가하였다. 수치 시뮬레이션 결과, 감쇠판의 모든 면적에 대해서 감쇠판을 부착한 원통형 부유체의 고유주기는 증가하였고, 감쇠판의 크기가 1.30D부터 입사파의 피크주기에서 heave RAO는 감소하였다. 감쇠판의 모든 면적에 대해서 원형 감쇠판이 Y자형 감쇠판보다 고유주기가 길게 나타나며, 고유주기의 차이는 감쇠판의 면적이 커질수록 그 차이가 커졌다. 운동응답 스펙트럼 계산 결과, 원형 감쇠판과 Y자형 감쇠판을 부착한 원통형 부유체의 heave 운동이 입사파의 피크주기에서 현저하게 감소하였다. 또한 원형 감쇠판을 부착한 원통형 부유체의 고유주기가 Y형 감쇠판을 부착한 경우보다 입사파의 피크 주기에서 더 멀리 이동하였다.

• 소음진동
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• 제7권1호
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• pp.153-159
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• 1997

In a stiffened plate reinforced on one of its sides by beam type stiffeners, the asymmetry about the plate mid-plane induces coupling between flexural wave and longitudinal wave. In this research interactions between flexural and longitudinal wave motion are analyzed in a stiffened plate which is reinforced only in one direction. The plate is modelled as a beam to which offset spring-mounted masses are attached at regular intervals. Propagation constants of the coupled waves and corresponding characteristic waves are derived by using periodic structure theory, and a computer code is developed. Also, sample calculations are carried out and the results are discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.616-622
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• 2001

In this paper, we analyzed the laminated composite sandwich plate structure of honeycomb core with changing values of the designing parameters. As a result, in designing parameters of that, the more height and thickness of the laminated composite plate's core, the more increase of natural frequency. The laminated angle has the maximum value when the plate of honeycomb core is join to opposite direction. This paper shows that the natural frequency of CFRP is higher than that of GFRP, and also impact strength marks maximum value in case of antisymmetry than symmetry of core. Also it shows that the mode shapes are various along with the angle-ply of laminated composite plate.

• 한국가시화정보학회지
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• 제13권1호
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• pp.21-25
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• 2015

Three-dimensional vortex structures in the corner region of translating normal plates are visualized experimentally with defocusing digital particle image velocimetry. Vortex formation processes for three plates with corner angle $60^{\circ}$, $90^{\circ}$, and $120^{\circ}$ are compared in order to study the effect of corner shape on vortex formation. In all cases, the self-induction of the starting vortex and its interaction with the potential flow induced by the moving plate cause the vortex to change its form dynamically after the plate starts to translate. While the vortex near a corner follows the plate in the low corner angle of $60^{\circ}$, the vortex separates early from the plate and its forward motion becomes slow in the high corner angle of $120^{\circ}$. It is also found that the starting vortex can transport inward at the corner, which depends on the corner angle.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.690-695
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• 2002

Two plate girders bridge has an advantage for execution of works and quality control because of its simplicity of super-structure caused by decreasing in amount of members and also is distinguished as aesthetic bridge type. Recently this has been adopted for structure of highway as well railway and introduced into domestic. In order to plan or design two plate girders bridge more rationably, it is necessary to comprehend its structural behavior as well as to consider the critical resign factors. Thus, in this study the formulation of optimum design for two plate girders bridge is proposed and the critical resign variables ani restraints are considered and founded by caring out optimum design. The objective function of optimization is formulated as a minimum cost design problem. And the thickness and length of I-shaped section are decided as resign variables. The design constraints are formulated based on Design Criteria for Railroad(Bridges). By comparing the optimum results with those of the conventional resign, the effectiveness of proposed optimum design formulation is investigated. From the results, the way to do optimum design of two plate girders bridge is suggested.

• 대한조선학회논문집
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• 제42권5호
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• pp.466-471
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• 2005

The out-of-plane deformation in thin plate structure has been a serious qualify problem. It has been known that the out-of-plane deformation is caused by the angular deformation of welded joint. However, experimental results show that the conventional theory based on angular deformation is not appropriate for prediction of the out-of-plane deformation in thin plate structure. In this study, large deformation plate theory is introduced to clarify the effect of residual stress on the out-of-plane deformation. A simple equation is proposed to predict the out-of-plane deformation. The results by the proposed method show good agreement with the experimental results.

• 한국해양공학회지
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• 제36권4호
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• pp.232-242
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• 2022

This study presents a method for level ice-structure interaction analysis to estimate the fatigue damage of arctic structures by applying plate theory to the behavior of level ice. The boundary element method (BEM), which incurs a lower computational cost than the finite element method (FEM), was introduced to solve the plate bending problem. The BEM formulation was performed by applying the BEM to plate theory. Finally, to check the validity of the proposed method, the BEM results and FEM results obtained using the ABAQUS commercial software were compared. The response results of the BEM analysis agreed well with those of the FEM analysis. Based on the results of the analysis, the BEM approach is considered to be very powerful in level ice-structure interaction analysis for estimating level ice-induced fatigue damage. Further work is being conducted to perform level ice fracture analysis based on the stress field calculated using the boundary element method.

• Steel and Composite Structures
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• 제26권4호
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• pp.463-471
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• 2018

The bolted end-plate beam-column connections have been widely used in steel structure and composite structure because of its excellent seismic performance. In this paper, the end-plate bolted connection is applied in the concrete structure, A new-type of fabricated beam-column connections with end-plates is presented, and steel plate hoop is used to replace stirrups in the node core area. To study the seismic behavior of the joint, seven specimens are tested by pseudo-static test. The experimental results show that the new type of assembly node has good ductility and energy dissipation capacity. Besides, under the restraint effect of the high-strength stirrup, the width of the web crack is effectively controlled. In addition, based on the analysis of the factors affecting the shear capacity of the node core area, the formula of shear capacity of the core area of the node is proposed, and the theoretical values of the formula are consistent with the experimental value.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 추계공동학술대회논문집
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• pp.107-112
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• 2002

기본적으로 선박의 판 부재로 구성되어 있고 선체구조의 전체적인 강도는 선체판의 강도와 강성에 지배를 받게 된다. 만약 국부적인 좌굴이 발생하게 되면 선체판의 강도는 급격하게 감소하게 된다 이러한 좌굴현상은 선박구조 전체에 심각한 영향을 미치게 되는데 좌굴은 구조강도평가에 있어서 중요한 실계요소 중 한가지이다. 이 연구논문에서는 압축하중이 작용하고 있는 선체판에 대해서 면내하중 변화를 연구하였으며 제안된 면내하중식은 탄성 혹은 탄소성 영역에서 좀더 만족할만한 설계를 하는데 있어서 좀더 효율적이라고 판단된다.

• 복합신소재구조학회 논문집
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• 제4권1호
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• pp.40-46
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• 2013

This paper presents the design, fabrication and performance of a reinforced concrete beam strengthened by GFRP box plate and its possibility for structural rehabilitations. The load capacity, ductility and failure mode of reinforced concrete structures strengthened by FRP box plate were investigated and compared with traditional FRP plate strengthening method. This is intended to assess the feasibility of using FRP box plate for repair and strengthening of damaged RC beams. A series of four-point bending tests were conducted on RC beams with or without strengthening FRP systems the influence of concrete cover thickness on the performance of overall stiffness of the structure. The parameters obtained by the experimental studies were the stiffness, strength, crack width and pattern, failure mode, respectively. The test yielded complete load-deflection curves from which the increase in load capacity and the failure mode was evaluated.