• Composites Research
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• v.15 no.5
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• pp.35-43
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• 2002

Presented in this paper are the results of an analytical investigation pertaining to the elastic buckling behavior of transversely isotropic plate with variable width subjected to unequal uniaxial compression forces at the ends and in-plane shear forces at the sides. The existing analytical solution developed for the isotropic plates is extended so that the transversely isotropic material properties can be taken into account in the plate buckling analyses. For the derivation of buckling equation the power series solution is employed. Graphical forms of results for finding the buckling strength of tapered plates are presented. In addition, the finite element analysis is also conducted. The results are compared and discussed.

• The Journal of Engineering Geology
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• v.3 no.3
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• pp.231-239
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• 1993

This paper presents a result on the determination of velocity distribution by a tomographic inversion of crosshole seismic traveltimes in transversely isotropic(aniso tropic) media. The crosshole traveltimes used in this study are synthetic ones computed by ray tracing for some models having isotropic and transversely isotropic velocity distributions. The traveltimes are inverted by a general ART and ansotropic ART which considers the transversely isotropic effect during inver sion. The aniotropic ART gives accurate velodty distributions of transversely isotropic and isotropic models, while the isotropic ART determines accurate velocities only for the isotropic model but inaccurate for the transversely isotropic one. Therefore, the anisotropic ART may be used in case where no information is known on the isotropy or transverse isotropy of a survey area.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.12
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• pp.1455-1463
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• 2009

Theoretical mechanics analysis and finite element simulation were performed to investigate creep deformation behavior at the crack tip of transversely isotropic materials under small scale creep (SCC) conditions. Mechanical behavior of material was assumed as an elastic-$2^{nd}$ creep, which elastic modulus ( E ), Poisson's ratio ( ${\nu}$ ) and creep stress exponent ( n ) were isotropic and creep coefficient was only transversely isotropic. Based on the mechanics analysis for material behavior, a constitutive equation for transversely isotropic creep behavior was formulated and an equivalent creep coefficient was proposed under plain strain conditions. Creep deformation behavior at the crack tip was investigated through the finite element analysis. The results of the finite element analysis showed that creep deformation in transversely isotropic materials is dominant at the rear of the crack-tip. This result was more obvious when a load was applied to principal axis of anisotropy. Based on the results of the mechanics analysis and the finite element simulation, a corrected estimation scheme of the creep zone size was proposed in order to evaluate the creep deformation behavior at the crack tip of transversely isotropic creeping materials.

• Tunnel and Underground Space
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• v.27 no.4
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• pp.243-252
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• 2017

Since the failure behavior of transversely isotropic rocks is significantly different from that of isotropic rocks, it is necessary to develop a transversely isotropic rock failure function in order to evaluate the stability of rock structures constructed in transversely isotropic rock masses. In this study, a spatial distribution function for strength parameters of transversely isotropic rocks is proposed, which is based on the Cassini oval curve proposed by 17th century astronomer Giovanni Domenico Cassini to model the orbit of the Sun around the Earth. The proposed distribution function consists of two model parameters which could be identified through triaxial compression tests on transversely isotropic rock samples. The original Mohr-Coulomb (M-C) failure function is extended to a three-dimensional transversely isotropic M-C failure function by employing the proposed strength parameter distribution function for the spatial distributions of the friction angle and cohesion. In order to verify the suitability of the transversely isotropic M-C failure function, both the conventional triaxial compression and true triaxial compression tests of transversely isotropic rock samples are simulated. The predicted results from the numerical experiments are consistent with the failure behavior of transversely isotropic rocks observed in the actual laboratory tests. In addition, the simulated result of true triaxial compression tests hints that the dependence of rock strength on intermediate principal stress may be closely related to the distribution of the microstructures included in the rock samples.

• Journal of KSNVE
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• v.7 no.3
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• pp.449-455
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• 1997

A theoretical study is presented for the prediction of the scattering of obliquely incident plane acoustic wave by transversely isotropic cylindrical shells immersed in water. In dorder to illustrate the vailidity of the theory backscattering form functions are compared with the existing results for degenerated problems: the catterings by isotropic shell and transversely isotropic solid cylinder. The unidirectional fiber reinforced boron-aluminum composites are selected as a model of transversely isotropic materials having potential applications in practice. From the resonant scattering analysis of the partial backscattering form functions, the dispersion curves for fluid-borne Stoneley wave, guided wave along the shell, and the lowest three Lamb type waves can be found. The Lamb type dispersions are compared with those of the flat plate. The variation of anisotropy significantly affects the properties of circumferential waves. From these results, it can be possible to identify parametrically the material properties of anisotropic cylindrical targets.

• Tunnel and Underground Space
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• v.14 no.5
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• pp.339-344
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• 2004

Variation of horizontal to vertical stress ratio of transversely isotropic rock caused by erosion was studied by numerical analysis. Influence of transversely isotropic was less than 5% for isotropic case. Difference between stresses obtained by numerical analysis and theoretical solution was small when initial stress ratio was small and the difference increased as erosion depth increased. Stress ratios diverged from initial ones as depth increased. An equation to determine stress ratio considering erosion according to the analyses was suggested.

• 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.

• Interaction and multiscale mechanics
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• v.3 no.2
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• pp.145-156
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• 2010

The propagation of waves in a micropolar transversely isotropic half space in the theory of thermoelasticity without energy dissipation are discussed. After developing the solution, the phase velocities and attenuation quality factor has been obtained. The expressions for amplitudes of stresses, displacements, microrotation and temperature distribution have been derived and computed numerically. The numerical results have been plotted graphically.

• Steel and Composite Structures
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• v.32 no.6
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• pp.779-793
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• 2019

The purpose of this research paper is to depict the thermomechanical interactions in transversely isotropic magneto thermoelastic solid with two temperatures and without energy dissipation in generalized LS theories of thermoelasticity. The Laplace and Fourier transform techniques have been used to find the solution of the problem. The displacement components, stress components, and conductive temperature distribution with the horizontal distance are computed in the transformed domain and further calculated in the physical domain numerically. The effect of two temperature and relaxation time are depicted graphically on the resulting quantities.

• Geomechanics and Engineering
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• v.19 no.1
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• pp.29-36
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• 2019

The present research deals with the deformation in transversely isotropic thin circular thermoelastic rotating plate due to time-harmonic sources. Frequency effect in the presence of rotation and two temperature is studied under thermally insulated as well as isothermal boundaries. The Hankel transform technique is used to find a solution to the problem. The displacement components, stress components, and conductive temperature distribution with the radial distance are computed in the transformed domain and further calculated in the physical domain using numerical inversion techniques. Some specific cases are also figured out from the current research.