| Summary: | 碩士 === 國立聯合大學 === 防災科技研究所 === 95 === According to the theory of elasticity, the analytical solutions of wave velocities and wave vectors are yielded for an inhomogeneous transversely isotropic medium whose Young’s moduli (E, E�S), and shear modulus (G�S) varied in terms of two models, namely, exponential and generalized power law with the increase of depth. However, the rest moduli of the transversely isotropic materials, ��, and ���S are remain constant throughout the depth. The generalized Hooke’s law, the strain-displacement relationships, and the equilibrium equations are integrated to constitute the governing equations. In these equations, using the displacement components as fundamental variables, and hence, three quasi wave velocities (VP, VSV, VSH) and wave vectors ( , , ) solutions can be derived for both models of inhomogeneous transversely isotropic media. The presented solutions are exactly the same as those of Daley and Hron (1977), and Levin (1979) when k=0 and c=0. In addition, by performing a parametric study, the results show that the magnitudes and directions of wave velocities and vectors are remarkedly affected by (1) the inhomogeneous parameters (k, a, b, c), (2) the type and degree of material anisotropy (E/E�S、G�S/E�S, ��/���S), (3) the phase angle (��), and (4) the depth of the medium (for the inhomogeneous type belonging to the generalized power law model). Consequently, to explore the behaviors of wave propagation in a transversely isotropic solid, it is imperative to consider the influence of inhomogeneity.
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