Three-dimensional wave propagation in a general anisotropic poroelastic medium: phase velocity, group velocity and polarization

Sharma, M. D.

doi:10.1111/j.1365-246x.2003.02141.x

Cited by 37 publications

(33 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The included gaseous or liquid phases have complicated responses to wave transmissions. As a result, it is extremely difficult to analytically formulate the equations of wave propagations in rocks for predicating wave performances, and to link the external characteristics of wave propagations with the physical properties of rocks, geometry of sub-structures, and responses of gaseous or liquid media [1][2][3][4][5][6][7] . Alternatively, people turned to apply the various strategies, such as laboratory tests, in-situ tests and computer simulations to measure and analyze wave performances .…”

Section: Introductionmentioning

confidence: 99%

Laboratory investigation on mechanisms of stress wave propagations in porous media

Yang

Yan-zhe³

et al. 2009

Sci. China Ser. E-Technol. Sci.

View full text Add to dashboard Cite

A number of porous models having the similar statistical characteristics of pores and physical properties with natural sandstones have been produced using reactive powder concrete (RPC) and polystyrenes. Spit-Hopkinson-Pressure -Bar tests and CT scans have been carried out on the models with the various porosities to probe the performance of wave propagations and the responses of pores and the matrix during wave propagations. It is shown that porosities significantly influence wave propagations. For an identical impact strain rate, the greater the porosity is, the larger the amplitude of the reflected wave appears, the more the peak in the reflected wave presents, and the smaller the amplitude of the transmitted wave turns out. A single peak emerges in the reflected wave when the porosity falls down to 5%. The larger the impact strain rate, the much remarkable the phenomena. The energy-dissipated ratio of porous models, i.e., W J /W I , linearly increases with the increment of porosities. The ratio is sensitive to the impact strain rate. Differences in the performance of wave propagations and energy dissipation result from the varied mechanisms that pores response to impacts. For the porosity less than 10%, the mechanism appears to be a process fracturing the matrix to generate new surfaces or pores. Energy has primarily been dissipated in creating new surfaces or pores. No apparent pore deformation takes place. The impact strain rate takes little effect on pore geometry. For the porosity of 15% or more, the mechanism works depending on the impact strain rate. When a low impact strain rate applies, the mechanism still appears to crack the matrix to generate surfaces or pores, but the amount is lower as compared to the case with a low porosity. If a large impact stain rate applies, the mechanism combines both fracturing the matrix and deforming the pores, with the deforming pores predominating. The vast majority of energy has been dissipated to deform pores. Only high porosity and impact strain rate can bring significant deformation to the pores. The proposed eccentricity of pores is capable of characterizing the geometry of pores and its change during wave propagations.

show abstract

Section: Introductionmentioning

confidence: 99%

Laboratory investigation on mechanisms of stress wave propagations in porous media

Yang

Yan-zhe³

et al. 2009

Sci. China Ser. E-Technol. Sci.

View full text Add to dashboard Cite

show abstract

“…Berryman and Wang (2001) and Pride and Berryman (2003) studied double-porosity problems. Sharma (2004) investigated the anisotropic poroelastic problems. Zhang and Li (1998) discussed the nature frequency problems in elastic medium.…”

Section: Introductionmentioning

confidence: 99%

A Numerical Method for Wave Propagation in Viscoelastic Stratified Porous Media

Zhang

2005

Transp Porous Med

View full text Add to dashboard Cite

This paper presents a numerical method, a transmission matrix method, for the wave propagation in viscoelastic stratified saturated porous media. The wave propagation in saturated media, based on Biot theory, is a coupled problem. In this stratified threedimensional model we do the Laplace transform for the time variable and the Fourier transform for the horizontal space coordinate. The original problem is transformed into ordinary differential equations with six independent unknown variables, which are only the function of the coordinate of depth. Thus, we get a transmission matrix of the wave problem for each layer. In the process of solution we use numerical method to calculate the eigenvalues and the eigenvectors of the transmission matrices. In the first step of the solution process we can obtain the wave field in the transformed space. The fast Fourier transform (FFT) method is used to do the inverse Laplace and the inverse Fourier transforms to get the solution in the time space. The detailed formulae are derived and some numerical examples are given.

show abstract

“…Elastic wave propagation in anisotropic media is of significant interest in geophysics and other such applied sciences as soil dynamics, earthquake engineering, and petroleum engineering [1].…”

Section: Introductionmentioning

confidence: 99%

Wave propagation in an inhomogeneous cross‐anisotropic medium

Wang

Lin

Jeng

et al. 2009

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

SUMMARYAnalytical solutions for wave velocities and wave vectors are yielded for a continuously inhomogeneous cross-anisotropic medium, in which Young's moduli (E, E ) and shear modulus (G ) varied exponentially as depth increased. However, for the rest moduli in cross-anisotropic materials, and remained constant regardless of depth. We assume that cross-anisotropy planes are parallel to the horizontal surface. The generalized Hooke's law, strain-displacement relationships, and equilibrium equations are integrated to constitute governing equations. In these equations, displacement components are fundamental variables and, hence, the solutions of three quasi-wave velocities, V P , V SV , and V SH , and the wave vectors, l P l SV , and l SH , can be generated for the inhomogeneous cross-anisotropic media. The proposed solutions and those obtained by Daley and Hron, and Levin correlate well with each other when the inhomogeneity parameter, k, is 0. Additionally, parametric study results indicate that the magnitudes and directions of wave velocity are markedly affected by (1) the inhomogeneous parameter, k; (2) the type and degree of geomaterial anisotropy (E/E , G /E , and / ); and (3) the phase angle, . Consequently, one must consider the influence of inhomogeneous characteristic when investigating the behaviors of wave propagation in a cross-anisotropic medium.

show abstract

Three-dimensional wave propagation in a general anisotropic poroelastic medium: phase velocity, group velocity and polarization

Cited by 37 publications

References 36 publications

Laboratory investigation on mechanisms of stress wave propagations in porous media

Laboratory investigation on mechanisms of stress wave propagations in porous media

A Numerical Method for Wave Propagation in Viscoelastic Stratified Porous Media

Wave propagation in an inhomogeneous cross‐anisotropic medium

Contact Info

Product

Resources

About