Influence of Heterogeneity on the Propagation Behavior of Love-Type Waves in a Layered Isotropic Structure

This paper aims to investigate the propagation of Love-type waves in the double layers lying over an isotropic homogeneous half-space. The two layers have been considered of finite width and a different sort of heterogeneities. Debye asymptotic expansion has been used to obtain the closed form of the dispersion equation. It has been found that the heterogeneity and width ratio of layers have a considerable effect on the phase velocity of Love-type waves. In particular, increment in the width ratio decreases the phase velocity of Love-type waves. The established dispersion relation for this study agrees well with the classical results. The comparative study of the present problem with a case in which double layers are homogeneous has been made. Results have been represented graphically, and it has been observed that the dimensionless phase velocity decreases with the increase in dimensionless wave number. It has also been examined that the heterogeneity parameter of uppermost layer and intermediate layer affects the phase velocity substantially.