We have developed a numerical model to represent the effect of injection test in unsaturated porous and fractured rock mass. The test was conducted at the LSBB (Laboratoire Souterrain à Bas Bruit) site close to Rustrel, Vaucluse, France in the field of the French ANR project called “HPPP-CO2”.

The results underline the impact of fractures on the hydro-mechanical response of the rock- mass. Indeed fractures allow a faster dissipation of the water pressures and stress variations induced by the water injection. Back analysis lead us to also estimate the rock mass intrinsic permeability and compressibility of the injected layer.