Damage around a keyed URL excavation: Change in permeability induced by microcracks growth

This paper presents a numerical modeling of damage extension around a keyed underground excavation using a continuous damage model. In the 3-dimensionnal code, FLAG^3D, we have implemented an anisotropic damage model. Triaxial compression tests provide a verification of the numerical implementation with a good agreement between experiments and predictions. The applicability of the implemented model to predict the damage development around a keyed elliptical tunnel of AECL’s Mine-by-experience with the break in damage between the tunnel walls and the head of key is examined. Results of the change in permeability induced by the microcracks growth and their connectivity around the keyed tunnel, are also discussed.