Numerical simulations of centrifuge experiments examining a sheet-pile wall with a liquefiable backfill are conducted and results are compared against the experimental responses to evaluate the numerical tools’ ability to accurately predict the seismic performance of this geosystem. The platform FLAC and the constitutive model PM4Sand are used for the simulations, and focus is placed on the sheet-pile wall displacements. The influence of relative density (DR) on the system's response is evaluated, together with the influence of other parameters such as the soil's permeability and numerical model construction method. The consideration of both mass-based and CPT-based DR estimates allows for a better prediction of the overall range of permanent sheet-pile wall displacements. Other parameters have a moderate to important effect on the estimated pre-shaking displacements but only a minor to moderate effect on the end-of-shaking wall displacements.