Abstract: A 3 dimension linear elastic model and a 3 dimension nonlinear elastic model of concrete arch dam are developed considering the dam and its foundation as an interactive system. Stochastic variables are introduced to analyze the models. A double curvature concrete arch dam is taken as an example, and the location and sequence of cracking elements are presented. It is pointed out that the other elements have less possibility to crack. After four elements crack at the dam heel, the stress state of the dam is thus improved, so it is necessary to take measures at dam heel such as bottom joint. Calculation results also show that linear elastic cracking analyses can replace nonlinear elastic analyses in stress analyses for an arch dam.