• 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.

• Journal of Korean Association for Spatial Structures
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• v.2 no.1 s.3
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• pp.59-65
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• 2002

The structures with many perforated openings are widely used as a load-carrying element in the fields of civil engineering works, top slab of prestressed concrete reactor vessel, petrochemical industries and the like. Perforated concrete plates are usually thick. Therefore, the effect of transverse shear deformation is not negligible. This paper describes a new analytical method of perforated plates combining both the finite element method for effective elastic constants and the usual method in solving orthotropic plate with transverse shear deformation.

• Journal of Korean Association for Spatial Structures
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• v.1 no.1 s.1
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• pp.95-108
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• 2001

A system of equations is developed for the theory of bending of thick orthotropic elastic plates which takes into account the transverse shear deformability of the plate. This system of equations is of such nature that three boundary conditions can and must be prescribed along the edge of the plate, i.e. ${\omega}=0,\;M_x=0,\;M_{xy}=0\;({\omega}=0,\;M_x=0,\;M_{xy}=0)$ at simple supported edges. It can be obtained general solution that is added complementary solution ${\omega}^e$ and paticular solution ${\omega}^p$ by an assumption of solution function. In the next paper, this analytical results will be obtained for perforated thick plates.

• Journal of Ocean Engineering and Technology
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• v.17 no.3 s.52
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• pp.21-26
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• 2003

An iteractive Kantorovich method is presented for the vibration analysis of rectangular orthotropic thick plates. Mindlin plate characteristic functions are derived in general forms using the Kantorovich method. Initially, Timoshenko beam functions consistent with the boundary conditions of the plate were used. Through numerical calculations of natural fairs of appropriate models, it has been confirmed that the method presented is superior to the Rayleigh-Ritz analysis or the finite element analysis in both accuracy and computational efficiency.

• Journal of the Society of Disaster Information
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• v.10 no.1
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• pp.1-14
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• 2014

This paper presents the three-dimensional stress analysis of orthotropic thick plates using the three-dimensional spline strip method based on the theory of elasticity. The orthotropic plates are made of Aragonite crystal and sitka spruce. To demonstrate the convergence and accuracy of the present method, several examples are solved, and results are compared with those obtained by other exact and numerical methods based on the theory of elasticity. Good convergence and accuracy are obtained. The effects of thickness/width ratio, aspect ratio and boundary conditions on normal stress distributions of Aragonite crystal plates and sitka spruce plates are investigated. Moreover, the difference of weak orthotropic and strong orthotropic properties given to the characteristics of stress distributions are also shown.

• Journal of Ship and Ocean Technology
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• v.4 no.2
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• pp.38-57
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• 2000

This paper deals with reliability analysis of specially orthotropic plates subjected to transverse lateral pressure loads by using Monte Carlo simulation method. The plates are simply supported around their all edges and have a low short span to plate depth ratio with rectangular plate shapes. Various levels of reliability analyses of the plates are performed within the context of First-Ply-Failure(FPF) analysis such as ply-/laminate-level reliability analyse, failure tree analysis and sensitivity analysis of basic design variables to estimated plate reliabilities. In performing all these levels of reliability analyses, the followings are considered within the Monte Carlo simulation method: (1) input parameters to the strengths of the plates such as applied transverse lateral pressure loads, elastic moduli, geometric including plate thickness and ultimate strength values of the plates are treated as basic design variables following a normal probability distribution; (2) the mechanical responses of the plates are calculated by using simplified higher-order shear deformation theory which can predict the mechanical responses of thick laminated plates accurately; and (3) the limit state equations are derived from polynomial failure criteria for composite materials such as maximum stress, maximum strain, Tsai-Hill, Tsai-Wu and Hoffman.

• Geomechanics and Engineering
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• v.16 no.2
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• pp.141-150
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• 2018

In this current work a quasi 3D "trigonometric shear deformation theory" is proposed and discussed for the dynamic of thick orthotropic plates. Contrary to the classical "higher order shear deformation theories" (HSDT) and the "first shear deformation theory" (FSDT), the constructed theory utilizes a new displacement field which includes "undetermined integral terms" and presents only three "variables". In this model the axial displacement utilizes sinusoidal mathematical function in terms of z coordinate to introduce the shear strain impact. The cosine mathematical function in terms of z coordinate is employed in vertical displacement to introduce the impact of transverse "normal deformation". The motion equations of the model are found via the concept of virtual work. Numerical results found for frequency of "flexural mode", mode of shear and mode of thickness stretch impact of dynamic of simply supported "orthotropic" structures are compared and verified with those of other HSDTs and method of elasticity wherever considered.

• Advances in Computational Design
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• v.3 no.2
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• pp.113-132
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• 2018

This paper presents the vibration and harmonic analysis of orthotropic laminated composite plate. The response of plate is determined using Finite Element Method. The eight noded shell 281 elements are used to analyze the orthotropic plates and results are obtained so that the right choice can be made in applications such as aircrafts, rockets, missiles, etc. to reduce the vibration amplitudes. Initially the model response for orthotropic plate and harmonic response for isotropic plate is verified with the available literature. The results are in good agreement with the available literature. Numerical results for the natural frequency and harmonic response amplitude are presented. Effects of boundary conditions, thickness to width ratio and number of layers on natural frequency and harmonic response of the orthographic plates are also investigated. The natural frequency, mode shape and harmonic analysis of laminated composite plate has been determined using finite element package ANSYS.

• 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.43 no.2
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• pp.253-271
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• 2012

To analyze the bending and transverse shear effects of laminated composite plates, a thirteen nodes triangular element will be presented. The suggested formulations consider a parabolic variation of the transverse shear strains through the thickness. As a result, there is no need to use shear correction coefficients in computing the shear stresses. The proposed element can model both thin and thick plates without any problems, such as shear locking and spurious modes. Moreover, the effectiveness of $w_{,n}$, as an independent degree of freedom, is concluded by the present study. To perform the accuracy tests, several examples will be solved. Numerical results for the orthotropic materials with different boundary conditions, shapes, number of layers, thickness ratios and fiber orientations will be presented. The suggested element calculates the deflections and stresses more accurate than those available in the literature.