Arch Appl Mech (2014) 84:235–245
DOI 10.1007/s00419-013-0796-8
ORIGINAL
Sanjeev A. Sahu · Pradeep K. Saroj · Nidhi Dewangan
SH-waves in viscoelastic heterogeneous layer
over half-space with self-weight
Received: 5 May 2013 / Accepted: 10 October 2013 / Published online: 29 October 2013
© Springer-Verlag Berlin Heidelberg 2013
Abstract The effect of gravity, heterogeneity and internal friction on propagation of SH-waves (horizontally
polarised shear waves) in viscoelastic layer over a half-space has been studied. Using the method of separation
of variables, dispersion equation has been obtained and used to recover the damped velocity of SH-waves. Both
the real and imaginary parts of dispersion equation are in well agreement with the classical Love wave equation.
It has been observed that heterogeneity of the medium affects the velocity profile of SH-wave significantly.
Some other peculiarities have been observed and discussed in our study.
Keywords SH-wave · Viscoelastic · Gravity · Internal friction · Heterogeneity
1 Introduction
The earth is considered to be a layered elastic medium with a variation in density and rigidity in constituent’s
layers. The study of body waves in a half-space is important to seismologists due to its possible applications
in geophysical prospecting and in understanding the cause and estimation of damage due to earthquakes.
In seismological studies, the phenomenon ‘liquefaction’ denotes a state in which solid deposit of sands
inside the ground is transformed into a state of suspension, so that they behave as a viscous liquid. Studies
of wave propagation in the earth stratum under loads have been done with assumption that the earth behaves
to a first approximation as an ideal elastic or viscoelastic material. The theory of viscoelasticity is of great
importance in the broad field of solid mechanics and particularly in seismology, exploration geophysics, etc.
Geophysical studies reveal the fact that the interior of earth, similar to the outer, is layered. To study the effect of
viscoelasticity in wave propagation, some attempts have been done earlier. Several papers have been published
on the propagation of seismic waves in elastic medium with different types of inhomogeneity. Bhattacharya [1]
pointed out some possible exact solution of SH-wave equation for inhomogeneous media. Cooper [2], Shaw
and Bugl [3], Schoenberg [4], Borcherdt [5], Kaushik and Chopra [6], Gogna and Chander[7] and Romeo [8]
have studied the propagation of SH-waves in viscoelastic media. The propagation of waves in a homogeneous
viscoelastic layer overlying a viscoelastic medium was studied by Kanai [9].
Lockett [10] discussed the reflection and refraction of waves in viscoelastic materials. Cerveny [11] studied
the propagation of SH-waves in viscoelastic media with and without heterogeneity. Chattopadhyay et al. [12]
S. A. Sahu (B ) · P. K. Saroj ·
Department of Applied Mathematics, Indian School of Mines, Dhanbad 826004, Jharkhand, India
E-mail: maths.sngv@gmail.com
Tel.: +91-326-2235917
Fax: +91-326-2296563
N. Dewangan
St. Guru Ghasidas Govt. PG college, Kurud, Chhattisgarh, India