• 제목/요약/키워드: Structural deformation

검색결과 2,817건 처리시간 0.028초

Preliminary Study on Deformation During Hydrostatic Testing in a Deep Tank

  • Kim, Geun-Gon;An, Tae-Hyun;Lee, Tak-Kee
    • 한국해양공학회지
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    • 제36권2호
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    • pp.115-124
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    • 2022
  • There are many different types of tanks on ships that meet various requirements. Each tank is required to undergo hydrostatic testing according to the Ship Safety Act after being installed onboard. In some hydrostatic tests, excessive deformation may occur. The overpressure of the air in the tank generated during testing is one of the possible causes of deformation. Based on the dimensions of the tank, nozzle, and pipes installed, it was confirmed that the overpressure of the air can cause problems with the structure, according to the Bernoulli equation. Additionally, finite element analysis (FEA) was performed on the tank structure to confirm the deformation and the stress occurring in the structure. From the perspective of deformation, the maximum deflection limit was set based on the criteria provided by the Eurocode and DNV. From the perspective of stress, the structural safety assessment was performed by comparing the allowable stress and equivalent stress generated in the structure. To determine whether the behavior of the actual structure was well implemented via FEA, beam theory was applied to the tank structure and compared with the FEA results. As a result of the analysis, severe deformation was found in some cases. This means that the overpressure of the air may be the cause of actual deformation. It was also confirmed that permanent deformation may occur.

회전관성 및 전단변형을 고려한 띠기초의 자유진동 (Free Vibrations of Strip Foundations with Rotatory Inertia and Shear Deformation)

  • 이준규
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.675-680
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    • 2006
  • This paper deals with the flexural free vibrations of strip foundations. Based on dynamic equilibrium equations of a beam element resting on Winkler foundation, differential equations governing free vibration of strip foundation are derived, in which effects of rotatory inertia and shear deformation are included. For obtaining the natural frequencies, differential equations are solved by numerical methods. As the numerical results, relationships between natural frequencies and various strip parameters are obtained and presented in Tables and Figures.

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전단변형을 고려한 이방성 적층판의 좌굴해석 (Buckling Analysis of Anisotropic Laminated Plates with Shear Deformation)

  • 최용희;권택진
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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    • pp.361-368
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    • 2001
  • This paper deals with the buckling load of antisymmetric angle-ply and cross-ply laminated rectangular plates. Buckling analysis is preformed for a simply supported, shear deformable laminated plate subjected to uniaxial compression and biaxial compression combined with uniform lateral pression. The shear deformation theory is considered to figure out a more exact behavior of laminated plates exactly. The purposes of this study are to formulate anisotropic laminated plates with shear deformation and to investigate the buckling load according to the various variables of laminated plates by using the exact solutions for anisotropic laminated plates having simply supported boundary.

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고주파 유도 가열에 의한 판 변형의 간이 수치 해석 (Numerical Analysis of Plate Deformation by Induction Heating)

  • 장창두;김호경;하윤석
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2002년도 봄 학술발표회 논문집
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    • pp.311-318
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    • 2002
  • In this study, we developed an analysis method of plate forming by induction heating and verified the effectiveness of the present method through a series of experiments. The phenomena of the induction heating is a 3D transient problem coupled with electromagnetic, heat transfer, and elastoplastic large deformation analyses. To solve the problem, we suggest a proper model and an integrated system. Using the present analysis model, we can estimate the plate deformation in heating without experiments and simulate the plate bending process of induction heating.

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Advanced Idealized Structural Units Considering Excessive Tension-Deformation Effects

  • Paik, Jeom-Kee
    • Journal of Hydrospace Technology
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    • 제1권1호
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    • pp.125-145
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    • 1995
  • In this paper, three kinds of the existing idealized structural units, namely the idealized beam-column units the idealized unstiffened plate unit and the idealized stiffened plate unit are expanded to deal with the excessive tension-deformation effects. A simplified mechanical model far the stress-strain relationship of steel members under tensile load is suggested. The 1/3-scale hull model for a leander class frigate under sagging moment tested by Dow is analyzed, and it is shown that the excessive tension-deformation is a significant factor affecting the progressive collapse behavior, particularly in the post-collapse range.

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Application of a fixed Eulerian mesh-based scheme based on the level set function generated by virtual nodes to large-deformation fluid-structure interaction

  • Hashimoto, Gaku;Ono, Kenji;Okuda, Hiroshi
    • Interaction and multiscale mechanics
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    • 제5권3호
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    • pp.287-318
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    • 2012
  • We apply a partitioned-solution (iterative-staggered) coupling method based on a fixed Eulerian mesh with the level set function to a large-deformation fluid-structure interaction (FSI) problem where a large-deformable thin structure moves in a high-speed flow field, as an airbag does during deployment. This method combines advanced fluid and structure solvers-specifically, the constrained interpolation profile finite element method (CIP-FEM) for fluid Eulerian mesh and large-deformable structural elements for Lagrangian structural mesh. We express the large-deformable interface as a zero isosurface by the level set function, and introduce virtual nodes with level sets and structural normal velocities to generate the level set function according to the large-deformable interfacial geometry and enforce the kinematic condition at the interface. The virtual nodes are located in the direction normal to the structural mesh. It is confirmed that application of the method to unfolded airbag deployment simulation shows the adequacy of the method.

Seismic behavior of high-strength concrete flexural walls with boundary elements

  • Kim, Seung-Hun;Lee, Ae-Bock;Han, Byung-Chan;Ha, Sang-Su;Yun, Hyun-Do
    • Structural Engineering and Mechanics
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    • 제18권4호
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    • pp.493-516
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    • 2004
  • This paper addresses the behavior and strength of structural walls with a concrete compressive strength exceeding 69 MPa. This information also enhances the current database for improvement of design recommendations. The objectives of this investigation are to study the effect of axial-load ratio on seismic behavior of high-strength concrete flexural walls. An analysis has been carried out in order to assess the contribution of deformation components, i.e., flexural, diagonal shear, and sliding shear on total displacement. The results from the analysis are then utilized to evaluate the prevailing inelastic deformation mode in each of wall. Moment-curvature characteristics, ductility and damage index are quantified and discussed in relation with axial stress levels. Experimental results show that axial-load ratio have a significant effect on the flexural strength, failure mode, deformation characteristics and ductility of high-strength concrete structural walls.

Studies into a high performance composite connection for high-rise buildings

  • Lou, G.B.;Wang, A.J.
    • Steel and Composite Structures
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    • 제19권4호
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    • pp.789-809
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    • 2015
  • This paper presents experimental and numerical studies into the structural behavior of a high performance corbel type composite connection adopted in Raffles City of Hangzhou, China. Physical tests under both monotonic and quasi-static cyclic loads were conducted to investigate the load carrying capacities and deformation characteristics of this new type of composite connection. A variety of structural responses are examined in detail, including load-deformation characteristics, the development of sectional direct and shear strains, and the history of cumulative plastic deformation and energy. A three-dimensional finite element model built up with solid elements was also proposed for the verification against test results. The studies demonstrate the high rigidity, strength and rotation capacities of the corbel type composite connections, and give detailed structural understanding for engineering design and practice. Structural engineers are encouraged to adopt the proposed corbel type composite connections in mega high-rise buildings to achieve an economical and buildable and architectural friendly engineering solution.

조향휠의 유형에 따른 구조안정성평가 (Evaluation on Structural Stability According to Steering Wheel Type)

  • 한문식;조재웅
    • 한국생산제조학회지
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    • 제21권5호
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    • pp.733-740
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    • 2012
  • This paper studies with structural and vibration analysis to evaluate the structural safety according to the types of steering wheels. This study models are two, three and four spoke types. As the number of spokes increases, the maximum equivalent stress becomes smaller but the maximum total deformation becomes a little higher. The natural frequency at three models are shown from 180 to 230Hz as the maximum deformation. The frequency responses as maximum amplitude displacement are happened at 200Hz, 500Hz and 500Hz respectively. In this study, the steering wheel with three spoke type is shown to become suitable at durability and production.

Effects of excess pore pressure dissipation on liquefaction-induced ground deformation in 1-g shaking table test

  • Wang, B.;Zen, K.;Chen, G.Q.;Kasama, K.
    • Geomechanics and Engineering
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    • 제4권2호
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    • pp.91-103
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    • 2012
  • Focusing on the effect of excess pore pressure dissipation on liquefaction-induced ground deformation, a series of 1-g shaking table tests were conducted in a rigid soil container by use of saturated Toyoura sand, the relative density of which was 20-60%. These tests were subjected to the sinusoidal base shaking with step increased accelerations: 100, 200, 300 and 400 Gals for 2-4 seconds. Shaking table tests were done using either water or polymer fluid with more viscous than water, thus varying the sand permeability of model tests. Excess pore pressures, accelerations, settlements and lateral deformations were measured in each test. Test results are presented in this paper and the effect of sand permeability on liquefaction and liquefaction-induced ground deformation was discussed in detail.