Rayleigh‐type wave propagation in exponentially graded initially stressed composite structure resting on rigid and yielding foundations

Highlights：

• The present study aims to investigate propagation behaviour of Rayleigh-type wave in composite structure composed of exponentially graded viscoelastic materials under initial stress.

• In particular, the upper stratum of the composite structure is constituted of Orthotropic viscoelastic material while lower stratum being constituted dry sandy viscoelastic sandy material.

• The characteristics of Rayleigh-type wave propagating in the considered composite structure is analysed for the two distinct cases viz. when the composite structure is resting on rigid foundation (Case I), and, when the structure is resting on a yielding foundation (Case II).

• Due to the dissipation involved in the system, the dispersion relation along with the attenuation coefficient for the Rayleigh type wave is obtained after using the admissible boundary conditions. As a special case of the problem, the obtained results are found in well agreement with the classical case.

• The numerical results are presented owing to the material properties of Carbon-fiber, Prepreg for the upper stratum, while, Sandstone, Limestone for the lower stratum and are illustrated graphically.

• The comparative analysis revealing the impact of viscoelasticity on different types of foundation on Rayleigh-type wave propagation caters to the salient feature of the study.