• 제목/요약/키워드: plate equation

검색결과 805건 처리시간 0.022초

Thermal vibration analysis of thick laminated plates by the moving least squares differential quadrature method

  • Wu, Lanhe
    • Structural Engineering and Mechanics
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    • 제22권3호
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    • pp.331-349
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    • 2006
  • The stresses and deflections in a laminated rectangular plate under thermal vibration are determined by using the moving least squares differential quadrature (MLSDQ) method based on the first order shear deformation theory. The weighting coefficients used in MLSDQ approximation are obtained through a fast computation of the MLS shape functions and their partial derivatives. By using this method, the governing differential equations are transformed into sets of linear homogeneous algebraic equations in terms of the displacement components at each discrete point. Boundary conditions are implemented through discrete grid points by constraining displacements, bending moments and rotations of the plate. Solving this set of algebraic equations yields the displacement components. Then substituting these displacements into the constitutive equation, we obtain the stresses. The approximate solutions for stress and deflection of laminated plate with cross layer under thermal load are obtained. Numerical results show that the MLSDQ method provides rapidly convergent and accurate solutions for calculating the stresses and deflections in a multi-layered plate of cross ply laminate subjected to thermal vibration of sinusoidal temperature including shear deformation with a few grid points.

회전하는 원통과 병진운동하는 평판사이의 윤활유동해석 (Analysis for Lubrication between a Rotating Cylinder and a Translating Plate)

  • 정호열;정재택
    • Tribology and Lubricants
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    • 제18권6호
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    • pp.411-417
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    • 2002
  • Two dimensional slow viscous flow between a rotating cylinder and a translating plate is investigated using Stokes' approximation. An exact formal expression of the stream function is obtained by using the bipolar cylinder coordinates and Fourier series expansion. From the stream function obtained, the streamline patterns are shown and the pressure distribution in the flow field is determined. By integrating the stress distributions on the cylinder, the farce and the moment exerted on the cylinder are calculated. The flow rate through the gap between the cylinder and the plate is also determined as a function of the distance between the cylinder and the plate. Special attention is directed to the case of very small distance between the cylinder and the plate concerned with the lubrication theory and the minimum pressure is calculated to explain a possible cavitation.

Stability analysis of transversely isotropic laminated Mindlin plates with piezoelectric layers using a Levy-type solution

  • Ghasemabadian, M.A.;Saidi, A.R.
    • Structural Engineering and Mechanics
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    • 제62권6호
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    • pp.675-693
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    • 2017
  • In this paper, based on the first-order shear deformation plate theory, buckling analysis of piezoelectric coupled transversely isotropic rectangular plates is investigated. By assuming the transverse distribution of electric potential to be a combination of a parabolic and a linear function of thickness coordinate, the equilibrium equations for buckling analysis of plate with surface bonded piezoelectric layers are established. The Maxwell's equation and all boundary conditions including the conditions on the top and bottom surfaces of the plate for closed and open circuited are satisfied. The analytical solution is obtained for Levy type of boundary conditions. The accurate buckling load of laminated plate is presented for both open and closed circuit conditions. From the numerical results it is found that, the critical buckling load for open circuit is more than that of closed circuit in all boundary and loading conditions. Furthermore, the critical buckling loads and the buckling mode number increase by increasing the thickness of piezoelectric layers for both open and closed circuit conditions.

점용접에 의하여 판재로 보강된 균열판의 수직응력에 의한 응력세기계수 (Stress Intensity Factor for the Cracked Sheet Subjected to Normal Stress and Reinforced with a Plate by Spot Welding)

  • 이강용;김옥환
    • Journal of Welding and Joining
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    • 제15권1호
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    • pp.55-65
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    • 1997
  • The stress intensity factor has been calculated for the cracked plate subjected to remote normal stress and reinforced with a plate by symmetric spot welding. The solution was based on displacement compatibility condition between the cracked sheet and the reinforcement plate. It is shown that the results from the derived equation for stress intensity factor were agreed with previous solutions. The reinforcement effect gets better as a joining spot is closer to the crack tip and the other joining spots become nearer to the crack surface.

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포스트 텐션 플랫 플레이트 해석을 위한 강성감소계수 (Stiffness Reduction Factor for Post-Tensioned Flat Plate Slabs)

  • 박영미;박진아;한상환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.125-126
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    • 2009
  • 유효보폭 모델은 횡하중하의 포스트 텐션(PT) 플랫 플레이트 골조 해석에 사용된다. PT 플랫 플레이트의 정확한 해석을 위해서 슬래브의 강성감소는 정확하게 평가되어야 한다. 이 목적을 위하여 본 연구는 기존 연구자들의 PT 플랫 플레이트 실험체를 수집하였으며. 반복적인 작업으로 실험체 강성에 수렴하는 유효보폭모델의 강성을 찾기 위하여 슬래브 폭을 감소시켰다. 이러한 데이터를 수집하여 비선형 회귀분석을 통하여 PT 플랫 플레이트의 강성 감소 계수식을 제안하였다.

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독립좌표연성법을 이용한 여러 개의 원형 구멍을 갖는 직사각형 평판의 자유진동해석 (Free Vibration Analysis of Rectangular Plate with Multiple Circular Cutouts by Independent Coordinate Coupling Method)

  • 곽문규;송명호
    • 한국소음진동공학회논문집
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    • 제17권11호
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    • pp.1086-1092
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    • 2007
  • This paper is concerned with the vibration analysis of a rectangular plate with multiple circular holes. On the contrary to the case of rectangular plate with multiple rectangular holes, it is very difficult to perform qualitative analysis on natural vibration characteristics because of geometrical inconsistency. In this paper, we applied the Independent Coordinate Coupling Method(ICCM) to the addressed problem, which was developed to compute natural vibration characteristics of the rectangular plate with a circular hole and proven to be computationally effective. The ICCM is based on Rayleigh-Ritz method but utilizes independent coordinates for each hole domain. By matching the deflection conditions for each hole imposed on the expressions, we can easily derive the reduced mass and stiffness matrices. The resulting equation is then used for the calculation of the eigenvalue problem. The numerical results show the efficacy of the Independent Coordinate Coupling Method.

내부판 구조물이 결합된 강 및 평직 복합재료 원통셸의 구조진동 특성 연구 (A Study on the Vibration Characteristics of Steel and Plain Weave Composite Cylindrical Shells Combined with Internal Plate Structures)

  • 이영신;최명환
    • 소음진동
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    • 제9권1호
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    • pp.149-162
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    • 1999
  • A method for the analysis of free vibrations of steel and plain weave composite cylindrical shells with a longitudinal, interior rectangular plate is developed by using the receptance method. This method is based on the ratio of a deflection (or slope) response to a harmonic force(or moment) at the joint. In this study, after getting the free vibration characteristics of the simply supported plate and shell, the frequency equation of the combined system is obtained by considering the continuity condition at the joint between the plate and the shell. The numerical results are compared with published results and experiment results in order to show the validate of the formulation, and shown that the analytical results agreed with those from other methods. The effects of the location and the thickness of the plate on the natural frequencies are also investigated.

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관 출구로부터 방출하는 약한 충격파의 평판충돌에 관한 연구 (The Impingement of a Weak Shock Wave Discharged from a Tube Exit upon a Flat Plate)

  • 이동훈;김희동;강성황
    • 소음진동
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    • 제10권6호
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    • pp.1035-1040
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    • 2000
  • The Impingement of a weak shock wave discharged from the open end of a shock tube upon a flat plate was investigated using shock tube experiments and numerical simulations. Harten-Yee Total Variation Diminishing method was used to solve axisymmetric, unsteady, compressible flow governing equations. Computations predicted the experimented results with a good accuracy. The peak pressure on the flat plate was not strongly dependent of the shock wave Mach number in the present range of Mach Number from 1.05 to 1.20. The distance between the plate and shock tube was changed to investigate the effect on the peak pressure. From both the results of experiments and computations we obtained a good empirical equation to predict the peak pressure on the flat plate.

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판의 찢김 응답에 대한 치수 및 동적 효과 (Scaling and Dynamic Effects on the Plate Cutting Response)

  • 백점기;이탁기
    • 대한조선학회논문집
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    • 제33권3호
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    • pp.48-55
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    • 1996
  • 본 연구의 목적은 좌초시 선저부의 찢김 응답에 대한 치수 및 동적 효과를 고찰하는 것이다. 이를 위해 판 및 종방향 보강재를 가진 보강판에 대해 판두께를 변화시킨 찢김 시리즈 실험을 수행하였으며, 본 실험 결과뿐 아니라 타연구자에 의해 수행된 기존의 찢김 실험 결과를 바탕으로 판의 찢김 응답에 대한 판두께의 치수 효과를 분석하였다. 또한, 기존의 이론적 및 실험적 연구 성과를 바탕으로 판의 찢김 응답에 대한 동적 효과를 고찰하였다. 특히, 연강재뿐 아니라 고장력강재의 항복강도에 대한 변형속도 효과를 정량적으로 규명하였다.

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강판 휨보강된 철근 콘크리트보의 구조적 거동 (Structural Behavior of RC Beam Strengthened with Steel Plate)

  • 오병환;강동욱;조재열;채성태;이명규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.598-604
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    • 1997
  • In recent years, strengthening by epoxy-bonded steel plates, carbon fiber sheets, aramid fiber sheets and so on, is spotlighted. Among them, the method using steel plates is most widely applied. Most studies have dealt with strengthening by epoxy-bonded steel plates. However the actual behavior of strengthened RC beams are not well established. Particularly, the studies on the separation load thar affects failure load of the beam are relatively insufficient. In this study, test parameters are the magnitude of pre-load, plate length, plate thickness, existence and spacing of anchor bolt, the number of plate layer and the height of side strengthening, 17reinforced concrete beams are strengthened by steel plates according to test parameters. Deflection, failure load, strains of reinforcing bar, concrete and plate are measured from tests(4 points loading). The failure mode, and separation load are analyzed from these measured data. The difference between Robert's theory and test results is discussed, and the prediction equation for separation load in the case of rip off is proposed.

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