• 제목/요약/키워드: Zero-thickness Element

검색결과 35건 처리시간 0.027초

무두께 요소층 확장을 이용한 육면체 격자의 세분화 기법 (A New All-Hexahedral Refinement Technique by Automatic Expansion of Zero-Thickness Element Layers)

  • 박철현;양동열
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 춘계학술대회논문집
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    • pp.323-326
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    • 2003
  • This paper presents a new algorithm that can refine hexahedral elements while maintaining the appropriate connectivity. In the algorithm, at first the regions of mesh to be refined are defined and, then, the zero-thickness element layers inserted into the interfaces between the regions. All the meshes in the regions, in which the zero-thickness layers are inserted, are to be regularized in order to improve the shape of the slender elements on the interfaces. This algorithm is applied to the analysis of plastic deformation process. The results show that the refined mesh gives smaller relative errors than the original mesh.

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무두께 요소층을 이용한 육면체 격자의 반복적 적응 격자 세분 (Adaptive mesh refinement for 3-D hexahedral element mesh by iterative inserting zero-thickness element layers)

  • 박철현;양동열
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 추계학술대회논문집
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    • pp.79-82
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    • 2004
  • In this study, a new refinement technique for 3-dimensional hexahedral element mesh is proposed, which is aimed at the control of mesh density. With the proposed scheme the mesh is refined adaptively to the elemental error which is estimated by 'a posteriori' error estimator based on the energy norm. A desired accuracy of an analysis i.e. a limit of error defines the new desired mesh density map on the current mesh. To obtain the desired mesh density, the refinement procedure is repeated iteratively until no more elements to be refined exist. In the algorithm, at first the regions of mesh to be refined are defined and, then, the zero-thickness element layers are inserted into the interfaces between the regions. All the meshes in the regions, in which the zero-thickness layers are inserted, are to be regularized in order to improve the shape of the slender elements on the interfaces. This algorithm is tested on a simple shape of 2-d quadrilateral element mesh and 3-d hexahedral element mesh. A numerical example of elastic deformation of a plate with a hole shows the effectiveness of the proposed refinement scheme.

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무두께 요소층을 이용한 육면체 격자의 세분화 기법 (A New All-Hexahedral Refinement Technique by Automatic Expansion of Zero Thickness Element Layers)

  • 박철현;양동열
    • 소성∙가공
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    • 제12권4호
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    • pp.334-339
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    • 2003
  • This paper presents a new algorithm that enables the refinement of hexahedral elements while maintaining the appropriate connectivity. In the algorithm, at first the regions of mesh to be refined are defined and, then, the zero-thickness element layers are inserted into the interfaces between the regions. All the meshes in the regions, in which the zero-thickness layers are inserted, are to be regularized in order to improve the shape of the slender elements on the interfaces. This algorithm is applied to the analysis of plastic deformation process. The results show that the refined mesh gives smaller relative errors than the original mesh.

Hydro-mechanical coupling algorithm of reinforced concrete lining in hydraulic pressure tunnel using cohesive elements

  • Li Zhou;Kai Su;Ding-wei Liu;Yin-quan Li;Hong-ze Zhu
    • Structural Engineering and Mechanics
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    • 제86권1호
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    • pp.139-156
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    • 2023
  • The reinforced concrete lining in the hydraulic pressure tunnel tends to crack during the water-filling process. The lining will be detached from the surrounding rock due to the inner water exosmosis along concrete cracks. From the previous research achievements, the cohesive element is widely adopted to simulate the concrete crack but rarely adopted to simulate the lining-rock interface. In this study, the zero-thickness cohesive element with hydro-mechanical coupling property is not only employed to simulate the traditional concrete crack, but also innovatively introduced to simulate the lining-rock interface. Combined with the indirect-coupled method, the hydro-mechanical coupling algorithm of the reinforced concrete lining in hydraulic pressure tunnels is proposed and implemented in the finite element code ABAQUS. The calculated results reveal the cracking mechanism of the reinforced concrete lining, and match well with the observed engineering phenomenon.

FINITE-ELEMENT METHOD FOR THE IMPEDANCE ANALYSIS OF TRAVELING-WAVE MODULATORS

  • JONG CHANG YI
    • 한국광학회:학술대회논문집
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    • 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.165-168
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    • 1989
  • A finite-element method is developed to calculate the impedance of arbitrarily shaped electrodes on traveling-wave modulators. This method employs the divergence theorem to obtain the total charge on an electrode from the node potential values. By using this method, the impedance of multi strip-line electrodes on anisotropic inhomogeneous dielectric media was analysed and the effect of non-zero electrode thickness was calculated.

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보강토 옹벽의 거동에 관한 유한요소 해석 (Finite Element Analysis of Reinforced Earth Wall Behavior)

  • 최인석;장연수;조광철
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.805-812
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    • 2003
  • The purpose of this study is to evaluate the behavior of a reinforced earth wall by modeling the properties of the interface between soil and reinforced elements as well as the non-linear stress-strain characteristics of soil. The effect of lateral earth pressures induced during construction is also included in the analyses. The interface element used to evaluate the relative movement of the interface between soil/reinforcement and soil/wall- facing has a zero thickness and essentially consists of normal and shear springs. The behavior of soil element is calculated based on the hyperbolic model. The computer program SSCOMPPC which includes the interface element, hyperbolic model and bi-linear model is applied in this study. From the analyses, it is showed that the locus of maximum tension were closed to the hi-linear failure line of theoretical analyses. The lateral displacement of SSCOMPPC is larger than that of the FLAC which adopts the elastic model. This means the analysis which is adopted the hyperbolic model and interface element induced more larger displacement.

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유한요소법을 이용한 샌드위치형 감쇠 보구조물의 진동해석 (Vibration Analysis of Damped Sandwich Beam Using Finite Element Method)

  • 서영수;정의봉;신준엽
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 춘계학술대회논문집
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    • pp.978-981
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    • 2005
  • The vibration analysis of damped sandwich beam is conducted using finite element method. The equation of motion presented by Mead and Markus is used to formulate FEM. Also as the thickness of the core in the damped sandwich beam goes to zero, conventional beam theory based on the transformed-section method and the equation of Mead and Markus are compared. According to the change of thickness and loss factor of the core, the forced frequency response of beam is calculated and discussed. And then using the half-power band width method, the damping ratio of each mode is calculated and discussed about each case.

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Finite element analysis of a piled footing under horizontal loading

  • Amar Bouzid, Dj.
    • Geomechanics and Engineering
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    • 제3권1호
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    • pp.29-43
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    • 2011
  • In this paper a semi-analytical approach is proposed to study the lateral behavior of a piled footing under horizontal loading. As accurate computation of stresses is usually needed at the interface separating the footing (pile) and the soil, this important location should be appropriately modeled as zero-thickness joint element. The piled footing is embedded in elastic soil with either homogeneous modulus or modulus proportional to depth (Gibson's soil). As the pile is the principal element in the piled footing system, a limited parametric study is carried out in order to investigate the influence of footing dimensions and the interface conditions on the lateral behavior of the pile. Hence, the pile behavior is examined through its main governing parameters, namely, the lateral displacement profiles, the bending moments, the shear forces and the soil reactions. The numerical results are presented for Poisson's ratio of 0.2 to represent a large variety of sands and Poisson's ratio of 0.5 to represent undrained clays.

콘크리트 충전 강관을 갖는 프리스트레스트 합성형 거더의 강-콘크리트 계면 거동 (Nonlinear Finite Element Analysis of Composite Girder with Concrete Infilled Tube)

  • 신동훈;김영훈;이타;강병수;이용학
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.386-389
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    • 2006
  • Prestressed composite girder bridges with concrete infilled steel tube at negative flexural moment region takes the advantages of enhancing local buckling and flexural resistances resulting from the lateral confining effect of concrete due to the interactive reaction in the interface layer of steel tube and concrete. The interface behavior in concrete infilled tube of the test composite girder is analyzed by 8-node zero thickness interface finite element combined with 3-D. elastoplastic concrete constitutive model and 3-D. elastoplastic Mindlin shell element. The interface effects between infillled concrete and steel tube are investigated through the comparision of the experimental and numerical results.

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불규칙 진동을 받는 복합 적층보의 응력 및 파괴해석 (Random Vibration Analysis of Composite Laminated Beams)

  • 전용선;강주원
    • 한국공간구조학회논문집
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    • 제2권4호
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    • pp.29-36
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    • 2002
  • The responses of composite laminated beams modeled with finite element and excited by stochastic loading are studied. The cantilevered laminated beam having a 5 ply configuration is considered. The beam is 1m long, 0.1m wide, and 0.02m thick, yielding a length to thickness ratio of L/h=50. The laminated beams was assumed to be made of Born Epoxy. The four nodes at the free end of the cantilever were loaded with identical zero-mean white noise excitations. Stress and failure analysis loaded with identical zero-mean white noise excitations is carried out. Along with the obtained results, comparison and discussion are presented for the cases of symmetric-ply, antisymmetric-ply, angle-ply, and cross-ply laminated beams.

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