• Title/Summary/Keyword: 평면응력

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Restrained Effect of End Plate on Plane Strain Test Evaluated by Digital Image Correlation Method (디지털 이미지 코릴레이션 기법으로 평가한 평면변형률 시험의 단부 구속 효과)

  • Jang, Eui-Ryong;Choo, Yoon-Sik;Lee, Won-Taeg;Chung, Choong-Ki
    • Journal of the Korean Geotechnical Society
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    • v.24 no.7
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    • pp.25-36
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    • 2008
  • The plane strain test can reproduce the real field condition and failure behavior precisely over other laboratory shear tests. Accordingly, this test has been utilized to investigate the shearing behaviors associated with overall failure behavior and local deformation of soils. However, most plane strain tests have been carried out with restrained end plates due to difficulties in manufacturing the equipment and also performing it. This restraint induces different results with real field because of shear stress on end plates. In this study, plane strain tests with/without bottom plate restraint were performed on Jumunjin-sand. The measurement of overall and local deformation was accomplished by digital image correlation technique as well as external LVDT. By applying digital image correlation method using two consecutive images captured through the transparent wall, local deformation behavior of various parts inside the specimen was estimated. And the formation and development of shear band caused by the restrained effect of end plate and the deformation mechanism of sand under plane strain condition were examined.

Yielding behavior and yield strength of plate structure containing softened region (연화부를 포함한 판재의 항복거동과 항복강도)

  • 배강열;김희진;이태열;엄동석
    • Journal of Welding and Joining
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    • v.8 no.3
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    • pp.79-88
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    • 1990
  • Welded joint often contains soft or softened regions such as the HAZ of TMCP steel welded with high heat input. In this study, the equivalent yield strength of plate structure containing softened region was predicted by FEM analysis, and its incremental behavior was explained with the results of the analysis. The calculated results of yield strength indicated the following for the plate structures. 1) As the softened region starts to yield, shear stress begins to build up along the boundary between base metal and softened region. This results in multi-axial stress condition which gives restraint on the softened region. 2) Restraint effect has a significant influence on the distribution of the shear stress, the nominal stress, and the strain. 3) The yielding behavior of softened region becomes the same as that of base metal when both ratios of length to width and thickness to width of softened region are larger than 30 and 13 respectively.

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Consolidated Undrained Triaxial on Cubical Compression and Plane Clay Specimen (입방체 점토시료에 대한 압밀 비배수 삼축압축 및 평면변헝률 시험)

  • 박경기;이강일
    • Geotechnical Engineering
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    • v.10 no.3
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    • pp.41-54
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    • 1994
  • This study aims at investigating the mechanism and operation of cubical triaxial test developed by Lade in order to obtain analysis on the clayey foundation deformation. A comparison on deviator stress, pore water pressure and stress path is made between test results of clay using the cubical consolidated undrained test as well as plane strain test.

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Time-domain Finite Element Formulation for Linear Viscoelastic Analysis Based on a Hereditary Type Constitutive Law (유전적분형 물성방정식에 근거한 선형 점탄성문제의 시간영역 유한요소해석)

  • 심우진;이호섭
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.8
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    • pp.1429-1437
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    • 1992
  • A new finite element formulation based on the relaxation type hereditary integral is presented for a time-domain analysis of isotropic, linear viscoelastic problems. The semi-discrete variational approximation and elastic-viscoelastic correspondence principle are used in the theoretical development of the proposed method. In a time-stepping procedure of final, linear algebraic system equations, only a small additional computation for past history is required since the equivalent stiffness matrix is constant. The viscoelasticity matrices are derived and the stress computation algorithm is given in matrix form. The effect of time increment and Gauss point numbers on the numerical accuracy is examined. Two dimensional numerical examples of plane strain and plane stress are solved and compared with the analytical solutions to demonstrate the versatility and accuracy of the present method.

Unsteady Thermoelasic Deformation and Stress Analysis of a FGM Rectangular Plate (경사기능재료 사각 판의 비정상 열 탄생변형과 응력해석)

  • Kim, Kui-Seob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.8
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    • pp.91-100
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    • 2004
  • A Green's function approach is adopted for analyzing the thermoelastic deformations and stresses of a plate made of functionally graded materials(FGMs). The solution to the 3-dimensional unsteady temperature is obtained by using the laminate theory. The fundamental equations for thermoelastic problems are derived in terms of out-plane deformation and in-plane force, separately. The thermoelastic deformation and the stress distributions due to the bending and in-plane forces are analyzed by using a Green's function based on the Galerkin method. The eigenfunctions of the Galerkin Green's function for the thermoelastic deformation and the stress distributions are approximated in terms of a series of admissible functions that satisfy the homogeneous boundary conditions of the rectangular plate. Numerical analysis for a simply supported plate is carried out and effects of material properties on unsteady thermoclastic behaviors are discussed.

Green's Function of Semi-Infinite Straight Interfacial Crack Problems (반무한 직선 계면균열문제에 관한 그린함수)

  • 최성렬;강기주
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.5
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    • pp.1530-1537
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    • 1991
  • 본 연구에서는 반무한 직선 계면균열의 상하면에 임의로 분포하는 어떠한 하 중에 대해서도 그 해석이 가능한 그린함수(Green's function)를 구하고자 한다. 이 를 위하여 반무한 직선 계면균열상의 임의의 한 점에 평면 집중하중이 작용하는 문제 와 비평면 집중전단하중이 작용하는 문제를 각각 택하였고, 이때 계면균열의 선단은 열려있다고 가정하였다. 이 문제를 풀므로써 균열선단부근의 응력성분을 결정하고 이로부터 그린함수의 의미를 지니는 응력강도계수에 대한 폐형해를 얻었다.

Transient Temperature Distribution, Thermal Stresses and Strains in a Composite Cylinder with a Concentric Hole (동심형(同心形) 구멍을 가진 복합(複合)실린더의 과도적(過渡的) 온도분포(溫度分布), 열응력(熱應力) 및 열변형도(熱變形度)의 해석(解析))

  • Eui-Jin,Jun;Hyo-Chul,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.11 no.1
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    • pp.35-44
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    • 1974
  • 열박음(shrink fitting)으로 인(因)한 동심형(同心形) 구멍을 가진 복합(複合)실린더의 과도적(過渡的) 온도분포(溫度分布), 열응력(熱應力) 및 열변형도(熱變形度)를 이론해석(理論解析)하였다. 온도분포해석(溫度分布解析)에서 외부(外部) 실린더는 균일온도(均一溫度)로 가열(加熱)되어, 실온(室溫)의 내부(內部) 실린더와 접촉면(接觸面)에서 일어나는 열전도(熱傳導)에 의(依)하여 냉각(冷却)되고, 외부(外部) 표면(表面)은 대기중(大氣中)에 노출(露出)된 상태(狀態)로 취급(取扱)하였다. 열응력(熱應力)은 평면변형도조건(平面變形度條件)을 만족(滿足)하는 것으로 생각하였으며, 물성(物性)은 온도(溫度)에 무관(無關)한 상수(常數)로 취급(取扱)하였다. 온도분포(溫度分布)는 열전도문제(熱傳導問題)만을 고려(考慮)함으로서도 유효(有效)한 해(解)를 얻을 수 있으며 열응력(熱應力)은 접촉면(接觸面)에서부터 형성(形成)되며, 반경방향응력(半徑方向應力)은 시간(時間)이 경과(經過)함에 따라 압축응력(壓縮應力)이 증가(增加)하여 접촉면(接觸面)에서 최대치(最大値)를 갖고, 원주방향응력(圓周方向應力)은 접촉면(接觸面)에서 초기(初期)부터 거의 최종상태(最終狀態)와 같은 크기를 갖음을 알 수 있다. 균일온도분포(均一溫度分布)가 이루어지면 열응력(熱應力)의 형성(形成)은 완료(完了)되게 되며, 이때의 열응력(熱應力)의 크기와 분포경향(分布傾向)은 평면응력조건(平面應力條件)을 사용(使用)하였다는 사실(事實)을 고려(考慮)하면 $Lam\acute{e}$의 이론해(理論解)와 일치(一致)함을 알 수 있었다.

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Shear Analysis of RC Structure using Evolutionary Structural Optimization (점진적 구조 최적화 기법을 이용한 철근 콘크리트 구조물의 전단 해석)

  • Kwak, Hyo-Gyoung;Yang, Kyu-Young;Shin, Dong-Kyu
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.3
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    • pp.319-328
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    • 2011
  • This paper introduces the construction of Strut-Tie model based on the Evolutionary Structural Optimization(ESO) method. Differently from conventional ESO method which uses plane stress elements, the introduced approach adopts the use of truss elements with the fact that the optimum topology of structures by ESO method is open a truss-like structure. Several examples are provided to demonstrate the capability of the proposed method in finding the best Strut-Tie models. In advance, it is shown that the introduced method is supported through the correlation studies between two-dimensional plane stress analysis and Strut-Tie models, and can be used effectively in practice, especially in shear design of complex reinforced concrete members where no previous experience is available.

Finite Element Analysis of Planar Effect on the Concrete Pavements (유한 요소법에 의한 콘크리트 포장 구조의 평면 거동연구)

  • Jo, Byung Wan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.5
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    • pp.1091-1096
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    • 1994
  • Since horizontal movements due to shrinkage and thermal gradients in concrete pavements involve no actual load, the stresses induced will be those due to closing of the pavement joints and subbase friction. Consequently, complete derivations of stiffness matrix and equivalent nodal loads due to planar effects on the concrete pavements was throughly undertaken using the finite rectangular elements with two degrees of freedom at each node. The numerical example shows that the tensile stress induced in a pavement due to concrete shrinkage might be negligible except at very long slab and very high coefficient of frictions. However the stresses in conjunction with principal traffic loads might cause cracking problems.

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Analysis of Elastic Constants of an Anisotropic Rock (이방성 암석의 탄성상수 분석연구)

  • 박철환
    • Tunnel and Underground Space
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    • v.11 no.1
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    • pp.59-63
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    • 2001
  • The total number of elastic constants of an anisotropic body is 9 and thus it is very difficult to measure these constants experimentally. The number of elastic constants can be reduced if a rock or rock mass is regarded as isotropic or transversely isotropic material. Since only 4 stress-strain relationships can be obtained, it is theoretically impossible to determine all 5 constants from a single uniaxial compression teat. Lekhnitskii overcame this problem by suggesting the fifth equation based on laboratory tests. But his equation is theoretically wrong and does not agree with experimental results. This paper describes the stress-strain relationships and the independent/dependent elastic constants of an anisotropic mass and suggests a testing mothed to determine 5 independent elastic constants for a transversely isotropic rock.

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