Discontinuum Models for Dam Foundation Failure Analysis

The safety assessment of concrete dam foundations entails the examination of the potential failure mechanisms, typically defined by natural rock discontinuities or the concrete-rock interface. Numerical models which represent the rock mass as a discontinuous medium, in particular discrete element models, are particularly adequate for the analysis of these failure scenarios, given their ability to represent the geologic structure of the rock mass, as well as the concrete structure. The application of discrete element deformable block models to the safety assessment of arch and gravity dam foundations is discussed with reference to specific examples. The issues involved in model generation, such as the representation of the rock discontinuities or the application of joint water pressures, are examined, as well as the procedures for safety factor evaluation.