Propagation and attenuation characteristics of Rayleigh waves in the irregular bottom of the ocean in porous half-spaces

Abstract

The Rayleigh wave propagation in the irregular bottom of the ocean, which is the interface of a homogeneous non-viscous liquid layer overlaying a porous half-space, under the influence of different factors has been discussed. The mathematical model is established by formula derivation. The propagation and attenuation characteristics of Rayleigh waves in a liquid layer over a transverse isotropy liquid-saturated porous half-space with irregular interface were studied. In addition, the dispersion and attenuation equations of the phase velocity and the attenuation coefficient with respect to the wave number were derived by which the effects of different parameters were analyzed. It was found that the magnitude of phase velocity varies with respect to the corrugation degree of the interface. In addition, irrespective of the type of interface, initially the attenuation coefficient rapidly increases and after the maximum value, it becomes constant. Furthermore, it has been observed that the change of the permeability coefficient affects the Rayleigh wave attenuation for the low wave number. For the low wave number, smaller permeability coefficient results in larger phase velocity and smaller attenuation. Moreover, both the phase velocity and the attenuation coefficient will eventually approach constant value in the high wave number region, for all parameters.

KEYWORDS:

• Rayleigh waves
• attenuation characteristics
• irregular interface
• soil properties

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The presented research work was funded by the National Key Research and Development Program of China (Project No. 2017YFC1500400), the National Natural Science Foundation of China (grant number 51878192&51991393), the Basic and Applied Basic Research Fund project of Guangdong Province (2020A1515011058), and the Innovation Research for the Postgraduates of Guangzhou University (No. 2019GDJC-D13).