The spent fuel of a nuclear power plant is generally stored in a wet storage pool. In case of a seismic event, one has to ensure the integrity of the spent fuel and structures holding them called spent fuel racks. In this study, a simple model accounting for 12 racks is proposed and compared with experimental results involving reduced scale racks. Fluid–structure interactions are modeled in terms of added coupling mass and damping, and free surface effects are accounted for. Comparison between simulations and experimental results showed good agreement. In spite of the simplicity of the model, simulations succeed to give a reasonable estimation of racks accelerations and were able to reproduce the effect of excitation amplitude and water level.