Abstract: To select the number of filling layer rationally and consider the influence of water level on deformation and stability is necessary in the numerical simulation of dam deformation and stability. Firstly, deformation and stability coefficient are selected as assessment indexes, and strength reduction method is introduced to calculate the stability coefficient of dam slope. Moreover, 3-D numerical model of layered filling is set up based on FLAC^3D to study the criteria of selecting the number of filling layer. Furthermore, on the basis of appropriate number of filling layer, the effect of water level on the deformation and stability of dam body is discussed. Results show that settlement is the predominant deformation and simulated settlements are closely related with the number of filling layer. Compared with settlement, horizontal displacement and safety factor are less sensitive to the number of filling layer which should be chosen according to the requirement of settlement precision; it is advised that the number of filling layer is not less than 10 layers, and the higher the dam, the more the number of filling layer should be. The horizontal displacement is more sensitive than the settlement and stability coefficient to water level of reservoir. These results are of guiding significance to determining the appropriate number of filling layer simulation.

Key words: layered filling, number of simulated filling layer, dam deformation, stability, settlement, stability coefficient, numerical siulation