• Structural Engineering and Mechanics
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• 제6권5호
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• pp.529-542
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• 1998

Generalised plane strain solution is presented for simply supported, angle-ply laminated hybrid plate under cylindrical bending. The arbitrary constants in the general solution of the governing differential equations are obtained from the boundary and interface conditions. The response of hybrid plates to sinusoidal loads is obtained to illustrate the effect of the thickness parameter and the ply-angle. The classical lamination theory and the first order shear deformation theory are also assessed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.703-709
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• 2001

In this paper, we analyzed the laminated composite sandwich plate structure of truss 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. In this type of structure, in the case of applying core of the laminated composite plate and antisymmetric stacking, natural frequency has high value and we calculated the optimum angle-ply making natural frequency maximum. Natural frequency of CFRP is higher than that of GFRP. Both are materials of the laminated composite plate. The mode shapes are various along with the angle-ply of the laminated composite plate.

• 한국강구조학회 논문집
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• 제9권1호통권30호
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• pp.65-79
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• 1997

Composite materials are consist of two or more different materials to produce desirable properties for structural strength. Because of their superiority in strength, corrosion resistance, and weight reduction, they are used extensively as structural members. The objective of this study is to present the effectivness of the laminated composite elements by analyzing in-plane displacement and stress of the anisotropic laminated annular elements. Anisotropic laminated structures are very difficult to analyze and apply, compared with isotropic and orthotropic cases for arbitrary boundaries and fiber angle -ply. Boundary conditions for the examples used in this study consist of two opposite edges clamped and the other two edges free, and finite difference method is used in this study for numerical analysis. From the numerical result, it is found that the program used in this study can be used to obtain the displacement of the straight beams considering it's transverse shear deformation as well as anisotropic laminated elements. Several numerical examples show the advantages of the stiffness increase when the angle-ply composite materials are used. Therefore it gives a guide in deciding how to make use of fiber's angle for the subtended angle, load cases, and boundary conditions.

• 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.

• 대한토목학회논문집
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• 제31권6A호
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• pp.409-415
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• 2011

Angle-Ply 적층쉘의 진동특성에 관한 최적화해석을 위해 1차전단변형이론에 의한 Ritz Method를 이용하여 이론적으로 해석하고, 수치해석에 의해 고유진동수와 진동모드를 해석하여 적층수, 쉘의 지지조건, 적층순서에 미치는 영향을 정량적으로 검토하여 적층복합원통쉘의 기본고유진동수의 최적화를 위한 최적인 적층구성에 미치는 영향을 명확히 규명하고자 한다.

• 한국안전학회지
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• 제22권5호
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• pp.41-49
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• 2007

In general, the curved structures have the engineering efficiency as well as a fine view compared with straight member. Also, composite materials are composed of two or more different materials to produce desirable properties for structural strength as compared to single ones. Shell structures with composite materials have many advantages in strength and weight reduction. Therefore, composite laminated conical shells are analyzed in this study. To solve differential equations of conical shells, this paper used finite difference method. Various parametric study according to the change of radius ratio, vertex angle and subtended angle are examined. The change of radius ratio, vertex angle and subtended angle mean the change from conical shells to cylindrical shells, conical shells to circular plates and open shells closed shells, respectively.

• 대한기계학회논문집
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• 제13권5호
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• pp.807-819
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• 1989

본 연구에서는 Donnell과 Flugge 셸 이론을 이용하여 단순지지된 비원형 단면을 가진 angle-ply 적층원통셸의 좌굴과 진동해석을 Soldatos의 해석과정을 따라 수행하고, 적층방법(stacking sequence)과 섬유각(fiber angle)의 변화에 따른 고유진 동수와 좌굴하중의 변화를 고찰하였으며, 초기 축하중을 받는 경우에 대한 고유진동수 의 변화에 대해서고 고찰하였다.

• 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.

• Steel and Composite Structures
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• 제34권1호
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• pp.141-154
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• 2020

In the present paper, free vibration analysis of angle-ply laminated composite annular and circular plates is performed by numerical methods. First-order shear deformation plate theory is used for kinematic relations. The related governing equations of motion are discretized via differential quadrature and discrete singular convolution methods. Frequency values are obtained for different lamina scheme, thickness-to-radius ratio, and mode numbers. The advantages and accuracy of these two methods are also tested in detail.

• Structural Engineering and Mechanics
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• 제14권3호
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• pp.245-262
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• 2002

The free vibration analysis of stiffened laminated composite plates has been performed using the layered (zigzag) finite element method based on the first order shear deformation theory. The layers of the laminated plate is modeled using nine-node isoparametric degenerated flat shell element. The stiffeners are modeled as three-node isoparametric beam elements based on Timoshenko beam theory. Bilinear in-plane displacement constraints are used to maintain the inter-layer continuity. A special lumping technique is used in deriving the lumped mass matrices. The natural frequencies are extracted using the subspace iteration method. Numerical results are presented for unstiffened laminated plates, stiffened isotropic plates, stiffened symmetric angle-ply laminates, stiffened skew-symmetric angle-ply laminates and stiffened skew-symmetric cross-ply laminates. The effects of fiber orientations (ply angles), number of layers, stiffener depths and degrees of orthotropy are examined.