Abstract：According to the virtual work principle，a 3D discontinuous finite element method for the stress-strain analysis of dam/foundation system is presented. In this method，the complex domain for the whole system can be divided into two unconcerned subdomains：the subdomain of dam and the subdomain of foundation，the grids between which are mutually dependent. The discontinuous grids are coupled by using the geometric compatibility equations for the foundation surface deformation and element displacements of foundation and two sides of dam，the constitutive equations of foundation surface and the equilibrium equations of the whole system. An example of gravity dam on complicated foundation is studied by this method. The study results are in accordance with those from the general finite element method；and the precision and validity of this method is proved. Because the meshes of dam and foundation are independent from each other，the preprocessing of the proposed method is relatively simple and even the grids can be generated parallelly. The method can be widely used in the deformation and stability analysis of dams under complicated geological conditions.
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2010, Vol. 29 
