Dynamics of Love-Type Waves in Orthotropic Layer Under the Influence of Heterogeneity and Corrugation

Subject Areas : Engineering

S.A Sahu ¹ , S Goyal ² , S Mondal ³

1 - Department of Applied Mathematics, IIT(ISM), Dhanbad-826004, India
2 - Department of Applied Mathematics, IIT(ISM), Dhanbad-826004, India
3 - Department of Applied Mathematics, IIT(ISM), Dhanbad-826004, India

Received: 2019-03-28 Accepted : 2019-05-23 Published : 2019-06-30

Keywords: Orthotropic layer, Elastic half-space, Love-type waves, Heterogeneity, Corrugation,

Abstract :

The present problem deals with the propagation of Love-type surface waves in a bedded structure comprises of an inhomogeneous orthotropic layer and an elastic half-space. The upper boundary and the interface between two media are considered to be corrugated. An analytical method (separation of variables) is adapted to solve the second order PDEs, which governs the equations of motion. Equations for particle motion in the layer and half-space have been formulated and solved separately. Finally, the frequency relation has been established under suitable boundary conditions at the interface of the orthotropic layer and the elastic half-space. Obtained relation is found to be in good agreement with the classical case of Love wave propagation. Remarkable effects of heterogeneity and corrugation parameters on the phase velocity of the considered wave have been represented by the means of graphs. Moreover, the group velocity curves are also plotted to exhibit the profound effect of heterogeneity considered in the layer. Results may be useful in theoretical study of wave propagation through composite layered structure with irregular boundaries.

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