The safe evaluation of the development of the damage areas of the Fengman Concrete Gravity Dam subjected to the earthquake is based on the plastic-damage model for concrete by the soft of ABAQUS. The damage variable which is the label of the damage of the material or the structure is considered as a internal variable. In this process of calculation the two variables

one for tensile damage and the other for compressive damage

is considered. The dam-reservoir dynamic interaction resulting from the transverse component of ground motion is modeled by using the developed and generalized Westergaard formula added mass technique. The hydrodynamic pressures resulting from the vertical component of ground motion are assumed to be small and are neglected in simulation. The safety and the overload potential of the Fengman concrete gravity is known by simulation. At the same time

it is concluded that the damage can be used to evaluate the safety of the dams subjected to the earthquake.