Abstract: Series of model tests have been carried out for studying the types of damage of embankment dams, the acceleration for incipient slip of the grains on the slope and the damping action on the slipping grain during earthquake. Results showed that there are two types of damage-crack and grain displacement, depent upon the characteristics of the dams. Based on the experiment the expression for the incipient slip acceleration is presented. Damping obeyed zero-two rule is confirmed. Method for estimating the displacement of a grain on slope of dam is suggested.