Lower bound analysis of modified pseudo‐dynamic lateral earth pressures for retaining wall‐backfill system with depth‐varying damping using FEM‐Second order cone programming

Realistic constitutive ground models are critical in the evaluation of soil-structure interaction problems and the assessment of key design parameters in the seismic analysis of infrastructure systems. In the present study, the modified pseudo-dynamic lateral earth pressures acting on retaining structure with granular backfill of depth-varying damping ratio are evaluated adopting the lower bound limit analysis in conjunction with the finite element (FE) discretization method using second-order cone programming (SOCP). The earthquake loading is simulated by the propagation of shear and primary waves through non-constant inertia forces in the horizontal and vertical directions, respectively. The influence of varying damping ratio alongside the retaining wall height on the seismic active and passive lateral earth pressures is effectively taken into account by adopting well-established formulas published in the literature. It is shown that failing to consider the damping variation with depth while performing the modified pseudo-dynamic analysis could lead to precarious, unrealistic estimates of design parameters.