The paper focuses on the seismic stability analysis of reinforced soil walls with a \(c-\varphi\) reinforced fill using the modified pseudo-dynamic approach. The limit equilibrium method is employed with the planar failure surface assumption to ascertain the required maximum tensile strength of reinforcement, its depth-wise distribution, and critical length under seismic loading conditions. The soil is modeled as viscoelastic materials to capture their dynamic behavior accurately. The study investigates the influence of various parameters, including normalized seismic frequency, damping ratio, shear strength parameters, surcharge loading and amplitude of initial base acceleration on the stability of the reinforced soil wall. One of the key aspects explored is the adjustment of reinforcement density with depth through modifications in spacing and length. Both uniform and nonuniform spacing arrangements are examined. The analysis reveals a similar trend in the required normalized tensile reinforcement force and normalized horizontal inertia forces with increasing normalized frequency. Conversely, the inclination of the failure surface demonstrates a reverse trend, suggesting a larger wedge failure. A nonuniform spacing arrangement offers a more economically viable design solution, requiring less critical reinforcement length to ensure stability under seismic conditions. The current findings are compared with existing modified pseudo-dynamic results, revealing a noteworthy alignment between them. Additionally, a comparison has been presented between the surcharge and equivalent height methods to enhance understanding of their respective representations of live load and dead load surcharges on reinforced soil walls.
