Refined conditions for nonlocal micropolar wave propagation in layered media

Abstract

This study extends the theory of nonlocal elasticity to investigate the propagation of Rayleigh waves in layered micropolar media. By employing asymptotic analysis, refined boundary and interface conditions are derived to accurately capture the effects of nonlocality and micropolarity. The derived conditions ensure equivalence between the integral and differential formulations of nonlocal elasticity. The propagation of Rayleigh waves in a layered micropolar medium is analyzed, as an application of the refined boundary and interface conditions. First-order corrected dispersion relations are obtained, accounting for the combined influence of nonlocality and micropolarity. Numerical simulations are conducted to visualize the impact of various parameters on the phase velocity of Rayleigh waves. The results demonstrate the significant role of nonlocal and micropolar effects in shaping the dispersion characteristics of surface waves. © The Author(s) 2025.