Efficacy of Surface Irregularity on Love waves Propagation in a Layered Double Porous Composite Rock Structure

Engineering structures in reservoir regions are often exposed to seismic risks, where surface waves such as Love waves can induce severe structural damage. This study presents a theoretical investigation of Love waves scattering in a double-porous composite structure with surface irregularity, a configuration representative of layered reservoir rocks. Employing the first-order perturbation technique, generalized expressions for the dispersion relation, phase velocity and group velocity are derived. The reflected displacement is also deduced for different irregularity geometries. The double-porosity framework, incorporating both storage and transport pores, provides a more realistic characterization of fluid-saturated geological media. Verification against existing results and limiting cases demonstrates excellent agreement, confirming the validity of the formulation. The analysis reveals that surface irregularity and double porosity strongly affect the dispersion behavior and reflection of scattered Love waves. These findings offer new insights into seismic response prediction, subsurface characterization, and the design of stable engineering structures in complex geological structures.