• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.4
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• pp.1-5
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• 2010

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

• Tunnel and Underground Space
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• v.5 no.4
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• pp.318-322
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• 1995

For transversely isotropic rocks such as schist, shale, etc, a method to determine the anisotropic elastic constants was proposed. Theoretically, equations of elastic constants E1, E2, and G2 can be derived from the measured strains in arbitrary three directions. If we attach three strain gages in accordance with the directons of anisotropy on the rock specimen under uni-axial compression, anisotropic elastic constants can be determined by these equations. With this method, the degree of anisotropy of transversely isotropic rocks will be easily evaluated by simple laboratory test.

• Geomechanics and Engineering
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• v.18 no.1
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• pp.85-96
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• 2019

A free vibration analysis and wave propagation of triclinic and orthotropic plate has been presented in this work using an efficient quasi 3D shear deformation theory. The novelty of this paper is to introducing this theory to minimize the number of unknowns which is three; instead four in other researches, to studying bulk waves in anisotropic plates, other than it can model plates with great thickness ratio, also. Another advantage of this theory is to permits us to show the effect of both bending and shear components and this is carried out by dividing the transverse displacement into the bending and shear parts. Hamilton's equations are a very potent formulation of the equations of analytic mechanics; it is used for the development of wave propagation equations in the anisotropic plates. The analytical dispersion relationship of this type of plate is obtained by solving an eigenvalue problem. The accuracy of the present model is verified by confronting our results with those available in open literature for anisotropic plates. Moreover Numerical examples are given to show the effects of wave number and thickness on free vibration and wave propagation in anisotropic plates.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.1
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• pp.71-78
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• 2008

We introduce the homogenized differential systems for fissured medium equations representing the small temperature variation or densities of a fluid in a system consisting of two components.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.2
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• pp.145-152
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• 1983

An adhesively bonded anisotropic structure containing a part-through crack subjected to in-plane mixed mode deformations is investigated. The problem is reduced to a pair of Fredholm integral equations of the second kind by mathematical analysis. By solving these equations numerically stress intensity factors k$_{1}$ and k$_{2}$ are presented. Two cases are considered with respect to fiber orientations. Case one is to fix the fiber orientations of sound plate bonded to cracked plate with various fiber orientations. The other is to vary fiber orientations for both plates. As boundary conditions, tension and shear loading respectively, are applied to bonded anisotropic plates to observe mixed mode deformations.

• Journal of the Optical Society of Korea
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• v.8 no.3
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• pp.137-146
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• 2004

A new method of obtaining the eigenmode of an anisotropic planar waveguide is studied. The planar waveguide can be composed of an arbitrary number of isotropic or uniaxially anisotropic layers, provided all the optical axes arc lying in the incidence plane. Since the equation of motion for the TE mode is not different from that for the TE mode in an isotropic planar waveguide, only the equation of motion for the TM mode is of any concern. For this kind of device structure, the Maxwell's equations can be solved for one component of the electric field and one component of the magnetic field. The resulting coupled set of equations is linear in the propagation constant and the eigenmode can be easily obtained using canned numerical routines.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.64-65
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• 2006

Anisotropic constitutive equations for sintering of metal powder compacts have been formulated from a linear viscous transversely-isotropic model in which an anisotropic sintering stress has been introduced to describe free sintering densification kinetics. The identification of material parameters defined in the model, has been achieved from thermomechanical experiments performed on 316L stainless steel warm-compacted powder in a dilatometer allowing controlled compressive loading.

• Journal of the Chungcheong Mathematical Society
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• v.19 no.4
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• pp.335-347
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• 2006

The homogenization of non-stationary Navier-Stokes equations on anisotropic heterogeneous media is investigated. The effective coefficients of the homogenized equations are found. It is pointed out that the resulting homogenized limit systems are of the same form of non-stationary Navier-Stokes equations with suitable coefficients. Also, steady Stokes equations as cell problems are identified. A compactness theorem is proved in order to deal with time dependent homogenization problems.

• Journal of Mechanical Science and Technology
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• v.16 no.7
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• pp.959-965
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• 2002

Effective hydraulic conductivity of a statistically anisotropic heterogeneous medium is obtained for steady two-dimensional flows employing stochastic analysis. Flow equations are solved up to second order and the effective conductivity is obtained in a semi-analytic form depending only on the spatial correlation function and the anisotropy ratio of the hydraulic conductivity field, hence becoming a true intrinsic property independent of the flow field. Results are obtained using a statistically anisotropic Gaussian correlation function where the anisotropy is defined as the ratio of integral scales normal and parallel to the mean flow direction. Second order results indicate that the effective conductivity of an anisotropic medium is greater than that of an isotropic one when the anisotropy ratio is less than one and vice versa. It is also found that the effective conductivity has upper and lower bounds of the arithmetic and the harmonic mean conductivities.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.75-78
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• 2003

In order to describe the Bauschinger and transient behavior of orthotropic fiber-reinforced composites, a combined isotropic-kinematic hardening law based on the non-linear kinematic hardening rule was considered here, in particular, based on the Chaboche type law. In this modified constitutive law, the anisotropic evolution of the back-stress was properly accounted for. Also, to represent the orthotropy of composite materials, Hill's 1948 quadratic yield function and the orthotropic elasticity constitutive equations were utilized. Furthermore, the numerical formulation to update the stresses was also developed based on the incremental deformation theory for the boundary value problems. Numerical examples confirmed that the new law based on the anisotropic evolution of the back-stress complies well with the constitutive behavior of highly anisotropic materials such as fiber-reinforced composites.