• Structural Engineering and Mechanics
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• v.41 no.5
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• pp.617-632
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• 2012

An isogeometric approach is presented for static analysis of thin plate problems of various geometries. Non-Uniform Rational B-Splines (NURBS) basis function is applied for approximation of the thin plate deflection, as for description of the geometry. The governing equation based on Kirchhoff plate theory, is discretized using the standard Galerkin method. The essential boundary conditions are enforced by the Lagrange multiplier method. Several typical examples of thin plate and thin plate on elastic foundation are solved and compared with the theoretical solutions and other numerical methods. The numerical results show the robustness and efficiency of the proposed approach.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.8 no.1
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• pp.81-92
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• 2004

Muskhelishvili's complex variable method has been applied to derive exact and closed expressions for Gaursat's functions for the first and second fundamental problems of the infinite plate weakened by a curvilinear hole which is conformally mapped on the domain outside the unit circle by means of rational mapping function. The hole having three poles. The previous work of the authers in this domain is considered as special cases of this work.

• Advances in concrete construction
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• v.15 no.2
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• pp.115-126
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• 2023

This paper investigates creep analysis of a plate made of Al-SiC functionally graded material using Mendelson's method of successive elastic solution. All mechanical and thermal material properties, except Poisson's ratio, are assumed to be variable along the thickness direction based on the volume fraction of reinforcement and thickness. First, the basic relations of the plate are derived using the Love-Kirchhoff plate theory. The solution of governing equations yields an elastic solution to start creep analysis. The creep behavior is demonstrated through Norton's equation based on Pandey's experimental results extracted for Al-SiC functionally graded material. A linear variation is assumed for temperature distribution along the thickness direction. The creep strain, as well as the thermal strain, are included in the governing equations derived from classical plate theory for mechanical strain. A successive elastic solution based on Mendelson's method is employed to derive the history of stresses, strains, and displacements over a long time. History of stresses and deformations are obtained over a long time to predict damage to the plate because of various loadings, and material composition along the thickness and planar directions.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.17-20
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• 2001

This paper presents the results of an elastic buckling analysis of elastically restrained orthotropic plate with a longitudinal stiffener under in-plane linearly distributed load. It is assumed that the loaded edges of web plate are simply supported and other two edges are elastically restrained against rotation. The stiffener is modeled as a beam element and its torsional rigidity is neglected. For the buckling analysis Lagrangian multiplier method is employed. The effects of restraint and longitudinal stiffener are presented in a graphical form.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.4
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• pp.22-30
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• 2001

In this paper, active control of vibrational intensity at a reference point in an infinite, elastic plate was discussed. The plate is excised harmonically by a vibrating source, which has a vertical point force. The optimal condition of controller was investigated to minimize the vibrational intensity being transmitted from the vibrating source to a reference point. Hence the method of feedforward control was employed for the control strategy and then the cost function was evaluated to find the optimal control force. Three types of control force (Vertical force, Moment, and Coupling force (a set of vertical force and moment) ) and controller's positions were examined to define the optimal condition of the controller. The vibrational intensity at a reference point was found to be reduced down to a zero level, compared with the uncontrolled case. Especially maximum reduction of vibrational intensity was achieved when the controller was collinearly positioned between a vibrating source and a reference point.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.327-334
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• 1998

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and toll.or structures, with irregular cross sections and with arbitrary boundary conditions was developed and reported by Kim, D. H. in 1974. In this paper, the result of application of this method to the special orthotropic plates with free edges supported on elastic foundation and with a pair of opposite edges under axial forces is presented. Such plates represent the concrete highway slab and hybrid composite pavement of bridges. The reinforced concrete slab can be assumed as a special orthotropic plate, as a close approximation. The highway slab is supported on elastic foundation, with free boundaries. Sometimes, the pair of edges perpendicular to the traffic direction may be subject to the axial forces. The plate is subject to the concentrated load/loads, in the form of traffic loads, or the test equipments. Any method nay be used to obtain the deflection influence surfaces needed for this vibration analysis. Finite difference method is used for this purpose, in this paper. The influence of the modulus of the foundation, the aspect ratio of the plate, and the magnitudes of the axial forces and the concentrated attached mass on the plate, on the natural frequency is thoroughly studied.

• Structural Engineering and Mechanics
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• v.88 no.2
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• pp.189-200
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• 2023

Silicate glass is usually a brittle and plate-like material, and it is difficult to measure the elastic modulus by the traditional method. This paper develops a test method for the glass elastic modulus based on the fundamental frequency of the cantilever beam with an elastic support and a free end. The method installs the beam-type specimen on a semi-rigid support to form an elastic support-free end beam. The analytic solution of the stiffness coefficients of the elastic support is developed by the fundamental frequency of the two specimens with known elastic modulus. Then, the glass elastic modulus is measured by the fundamental frequency of the specimens. The method significantly improves the measurement accuracy and is suitable for the elastic modulus with the beam-type specimen whether the glass is homogeneous or not. Several tests on the elastic modulus measurement are conducted to demonstrate the reliability and validity of the test method.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.2
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• pp.133-140
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• 2005

A Plate on the elastic half-space may be generally be analyzed by the finite element method. However, there ate some difficulties to obtain the flexibility matrix of the foundation based on the Boussinesq's theory. In this study, an efficient numerical procedure which uses the analysis results of the vertical displacements due to the uniformly distributed loading in a circular area is presented. Some numerical examples represent better results than those of numerical integration technique or subsection method especially in the case of irregular mesh pattern.

• Coupled systems mechanics
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• v.6 no.3
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• pp.287-316
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• 2017

This paper studies the particularities of the forced vibration of the hydro-elastic system consisting of a moving elastic plate, compressible viscous fluid and rigid wall. This study is made by employing the discrete-analytical solution method proposed in the paper by the authors (Akbarov and Panakhli (2015)). It is assumed that in the initial state the fluid flow is caused by the axial movement of the plate and the additional lineally-located time-harmonic forces act on the plate and these forces cause additional flow field in the fluid and a stress-strain state in the plate. The stress-strain state in the plate is described by utilizing the exact equations and relations of the linear elastodynamics. However, the additional fluid flow field is described with linearized Navier-Stokes equations for a compressible viscous fluid. Numerical results related to the influence of the problem parameters on the frequency response of the normal stress acting on the plate fluid interface plane and fluid flow velocity on this plane are presented and discussed. In this discussion, attention is focused on the influence of the initial plate axial moving velocity on these responses. At the same, it is established that as a result of the plate moving a resonance type of phenomenon can take place under forced vibration of the system. Moreover, numerical results regarding the influence of the fluid compressibility on these responses are also presented and discussed.

• International Journal of Korean Welding Society
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• v.5 no.1
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• pp.29-34
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• 2005

Finite element analysis (FEA) and experimental studies on an elastic bending method have been performed in order to control the angular distortion at the fillet weldment for curved panel. Process parameters for the elastic bending method such as clamping span and release time were analyzed with reference to welding condition and geometric effect of the curved panel, which can minimize or prevent the angular distortion by producing a proper skin stress to the fillet weldment. The amounts of the angular distortion decrease almost in a linear manner with an increase in the skin stress. The skin stress required for non-angular distortion at the fillet weldment is strongly dependent on the plate thickness, not the heat intensity applied. The clamping span for obtaining uniform skin stress was defined as functions of the plate thickness and length of the free edge. Clamp should be removed after the fillet weldment is cooled down to room temperature for non-angular distortion. Effectiveness of the elastic bending method established was verified by its application to an actual curved panel.