Generalized Rayleigh Wave Propagation in Heterogeneous Substratum Over Homogeneous Half-Space Under Gravity

Purpose The purpose of study to this article is to analyze the Rayleigh wave propagation in an isotropic dry sandy thermoelastic half-space. Various wave characteristics, i.e wave velocity, penetration depth and temperature have been derived and represented graphically. The generalized secular equation and classical dispersion equation of Rayleigh wave is obtained in a compact form. Design/methodology/approach The present article deals with the propagation of Rayleigh surface wave in a homogeneous, dry sandy thermoelastic half-space. The dispersion equation for the proposed model is derived in closed form and computed analytically. The velocity of Rayleigh surface wave is discussed through graphs. Phase velocity and penetration depth of generated quasi P, quasi SH wave, and thermal mode wave is computed mathematically and analyzed graphically. To illustrate the analytical developments, some particular cases are deliberated, which agrees with the classical equation of Rayleigh waves. Findings The dispersion equation of Rayleigh waves in the presence of thermal conductivity for a dry sandy thermoelastic medium has been derived. The dry sandiness parameter plays an effective role in thermoelastic media, especially with respect to the reference temperature for η = 0.6,0.8,1. The significant difference in η changes a lot in thermal parameters that are obvious from graphs. The penetration depth and phase velocity for generated quasi-wave is deduced due to the propagation of Rayleigh wave. The generalized secular equation and classical dispersion equation of Rayleigh wave is obtained in a compact form. Originality/value Rayleigh surface wave propagation in dry sandy thermoelastic medium has not been attempted so far. In the present investigation, the propagation of Rayleigh waves in dry sandy thermoelastic half-space has been considered. This study will find its applications in the design of surface acoustic wave devices, earthquake engineering structural mechanics and damages in the characterization of materials.

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Generalized Rayleigh wave propagation in a covered half-space with liquid upper layer

STRUCTURAL ENGINEERING AND MECHANICS ◽

10.12989/sem.2015.56.3.491 ◽

2015 ◽

Vol 56 (3) ◽

pp. 491-506 ◽

Cited By ~ 1

Author(s):

Masoud Negin

Keyword(s):

Wave Propagation ◽

Rayleigh Wave ◽

Half Space

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Effect of external electric field on the characters of Rayleigh wave propagation in a piezoelectric half-space

2013 Symposium on Piezoelectricity, Acoustic Waves, and Device Applications ◽

10.1109/spawda.2013.6841112 ◽

2013 ◽

Author(s):

Chun-long Gu ◽

Feng Jin

Keyword(s):

Wave Propagation ◽

Electric Field ◽

Rayleigh Wave ◽

External Electric Field ◽

Half Space

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Torsional surface wave propagation in an initially stressed non-homogeneous layer over a non-homogeneous half-space

Applied Mathematics and Computation ◽

10.1016/j.amc.2012.09.058 ◽

2012 ◽

Vol 219 (6) ◽

pp. 3209-3218 ◽

Cited By ~ 7

Author(s):

Shishir Gupta ◽

Dinesh Kumar Majhi ◽

Sumit Kumar Vishwakarma

Keyword(s):

Wave Propagation ◽

Surface Wave ◽

Half Space ◽

Homogeneous Layer ◽

Homogeneous Half Space ◽

Surface Wave Propagation ◽

Torsional Surface Wave

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Influence of material damage on Rayleigh wave propagation along half-space boundary

Computational Continuum Mechanics ◽

10.7242/1999-6691/2019.12.3.25 ◽

2019 ◽

Vol 12 (3) ◽

pp. 293-300 ◽

Cited By ~ 1

Author(s):

A.M. Antonov ◽

V.I. Erofeev ◽

A.V. Leonteva

Keyword(s):

Wave Propagation ◽

Rayleigh Wave ◽

Half Space ◽

Material Damage ◽

Space Boundary

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Rayleigh wave equations with couple stress: modeling and dispersion characteristic

Geophysics ◽

10.1190/geo2020-0890.1 ◽

2021 ◽

pp. 1-64

Author(s):

Yanqi Wu ◽

Jianwei Ma

Keyword(s):

Wave Propagation ◽

Half Space ◽

Scale Effect ◽

Linear Elasticity ◽

Rayleigh Waves ◽

Couple Stress ◽

Characteristic Length ◽

Couple Stress Theory ◽

Stress Theory ◽

Homogeneous Half Space

In elastostatics, the scale effect is a phenomenon in which the elastic parameters of a medium vary with specimen size when the specimen is sufficiently small. Linear elasticity cannot explain the scale effect because it assumes that the medium is a continuum and does not consider microscopic rotational interactions within the medium. In elastodynamics, wave propagation equations are usually based on linear elasticity. Thus, nonlinear elasticity must be introduced to study the scale effect on wave propagation. In this work, we introduce one of the generalized continuum theoriescouple stress theoryinto solid earth geophysics to build a more practical model of underground medium. The first-order velocity-stress wave equation is derived to simulate the propagation of Rayleigh waves. Body and Rayleigh waves are compared using elastic theory and couple stress theory in homogeneous half- space and layered space. The results show that couple stress causes the dispersion of surface waves and shear waves even in homogeneous half-space. The effect is enhanced by increasing the source frequency and characteristic length, despite its insufficiently clear physical meaning. Rayleigh waves are more sensitive to couple stress effect than body waves. Based on the phase-shifting method, it was determined that Rayleigh waves exhibit different dispersion characteristics in couple stress theory than in conventional elastic theory. For the fundamental mode, the dispersion curves tend to move to a lower frequency with an increase in characteristic length l. For the higher modes, the dispersion curves energy is stronger with a greater characteristic length l.

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