Effect of foundation models on seismic response of arch dams

•Parametric analysis of semi-unbounded foundation models is performed comprehensively.•Nonlinear seismic response of arch dams is affected by the material damping and the simulation size of foundation.•We propose to neglect the material damping of foundation when the wave incident mechanism is used.•The realistic non-uniformity of foundation should be considered in the earthquake response analysis of arch dams.