• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.2
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• pp.76-80
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• 2003

In this study, it is presented analysis results of bending problems in the orthotropic thick plates and the orthotropic thin plates. Finite element method in this analysis was used. Both Kirchoffs assumptions and Mindlin assumptions are used as the basic governing equations of bending problems in the orthotropic plates. The analysis results are compared between the orthotropic thick plates and the orthotropic thin plates for the variations of thickness-width ratios.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.258-264
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• 1999

In this study, a computer program was developed for analysis of the orthotropic curved ring sector plates. In the developing program , the thin-plate theory and multi-base coordinate system was adopted. The effect of design factors-boundary conditions, loading conditions, steel ratio, open angle, radius of curvature and relative flexural rigidity between slab and edge-beam-on the behavior of the circular ring sector plates were discussed. Also, the practical limitations was proposed to replace the problem of the orthotropic sector plate by equivalent rectangular plage.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.387-395
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• 1991

Large deflection behavior of cylindrically orthotropic thin circular plates is investigated by the numerical technique of differential quadrature. Governing equations are derived in terms of transverse deflection and stress function and a Newton-Raphson technique is used to solve the nonlinear systems of equations. For small values of degree of differential quadrature (N.leq.13), as the degree of differential quadrature increases, the center deflection converges. However, as N increases further, the center deflection diverges by ill-conditioning in the weighting coefficients. As the orthotropic parameter increases, the center deflection decreases and behaves linear for the loads. At center, the stress is affected mainly by orthotropic parameter, while the stress is affected mainly by boundary condition at edge.

• Structural Engineering and Mechanics
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• v.4 no.5
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• pp.541-552
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• 1996

This paper is concerned with the structural optimization problem of maximizing the compressive buckling load of orthotropic rectangular plates for a given volume of material. The optimality condition is first derived via variational calculus. It states that the thickness distribution is proportional to the strain energy density contrary to popular claims of constant strain energy density at the optimum. An engineers physical meaning of the optimality condition would be to make the average strain energy density with respect to the depth a constant. A double cosine thickness varying plate and a double sine thickness varying plate are then fine tuned in a one parameter optimization using the Rayleigh-Ritz method of analysis. Results for simply supported square plates indicate an increase of 89% in capacity for an orthotropic plate having 100% of its fibers in $0^{\circ}$ direction.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.1
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• pp.49-57
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• 1986

The vibrations problem of thin orthotropic skew plates of linearly varying thickness is analyzed using the small deflection theory of plates. Using dimensionless oblique coordinates, the deflection surface can be expressed as a polyonmial series satisfying the boundary conditions. For orthotropic plates which is clamped on all the four edges, numerical results for the first two natural frequencies are presented for various combinations of aspect ratio, skew angle and taper parameter. The properties of material used are one directional glass fibre reinforced plastic GFRP. The results obtained may be summarised as follows: 1. In case of the first mode vibration of plates with increase in the skew angle, the natural frequencies of plates decrease. 2. As the aspect ratio decrease, the natural frequencies of plates decrease. 3. For the identical skew angle, natural frequencies of plates increase with the taper parameter of thickness.

• Computers and Concrete
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• v.26 no.5
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• pp.421-427
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• 2020

In this study, the two-dimensional generalized finite integral transform(FIT) approach was extended for new accurate thermal buckling analysis of fully clamped orthotropic thin plates. Clamped-clamped beam functions, which can automatically satisfy boundary conditions of the plate and orthogonality as an integral kernel to construct generalized integral transform pairs, are adopted. Through performing the transformation, the governing thermal buckling equation can be directly changed into solving linear algebraic equations, which reduces the complexity of the encountered mathematical problems and provides a more efficient solution. The obtained analytical thermal buckling solutions, including critical temperatures and mode shapes, match well with the finite element method (FEM) results, which verifies the precision and validity of the employed approach.

• Bulletin of the Society of Naval Architects of Korea
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• v.18 no.2
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• pp.1-6
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• 1981

The buckling of stiffened plates is considered using a finite element method. In this paper stiffened plates are treated as orthotropic plates and by appling Mindlin's plate theory the effects of shear deformation to buckling loads are considered. In general, it is found that for moderately thick plates Mindlin's plate theory gives lower buckling load than those obtained using classical thin plate theory.

• Structural Engineering and Mechanics
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• v.39 no.1
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• pp.115-123
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• 2011

The present work deals with obtaining the critical buckling load and the natural frequencies of clamped, orthotropic, rectangular thin plates subjected to different linear distributed in-plane forces. An analytical solution is proposed. Using the Ritz method, the dependence between in-plane forces and natural frequencies are estimated for various plate sizes, and some results are compared with finite element solutions and where possible, comparison is made with previously published results. Beam functions are used as admissible functions in the Ritz method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.8
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• pp.1485-1492
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• 1992

While the vibration of circular plates were considered by many researchers, rather less attention is given to elliptical plates. In the present paper, the Rayleigh-Ritz mothod is used to obtain an eigenvalue equation for the free flexural vibration of thin elliptical plates having the classical free, simply suported or clmped boundary condition. Circular plates are included as a special case of the elliptical plates. Products of simple polynomials are used as the admissible functions and a recurrence relationship facilitates the evaluation of the necessary integrals. The analysis is developed for rectilinear orthotropic plates but the numerical results are given for isotropic plates with various aspect ratios.

• Journal of Korean Association for Spatial Structures
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• v.1 no.1 s.1
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• pp.109-115
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• 2001

Composite materials also known as fiber reinforced plastics have been developed and used in many engineering applications due to their outstanding mechanical properties. Laminated plates as structural components that are made of in composite material are widely used. Therefore, nonlinear response of laminated composite plates modeled with finite elements and excited by stochastic loading is studied. The classical laminated plate theory is used to account for the variation of strains through the thickness for modeling laminated thin plates. Approximate nonlinear random vibration analysis is performed using the method of equivalent linearization to account for material non-linearity.