The contact stiffness bounds when DDA is applied to the analysis of the gravity dam stability

It is a key problem to evaluate accuratety the gravity dam stability under the complicated geological situations.Traditionally,it usually employs Rigid Limit Equilibrium Method and non-line Finite Element Method,but all those methods have limitations.Taking Wudu as the example,this paper researched the values of the contact stiffness when the DDA is applied to analyzing the gravity dam stability.The paper studied the effect of the contact stiffness on the stress distribution,the whole safety factor and the local safety factor.The results demonstrate that the contact stiffness has little influence on the foundation whole safety factor but larger influence on the deep whole stability factor as well as the local safety factor.