Verification and validation of flow and transport in cracked saturated porous media

Study of presence of cracks in porous media and their effect on fluid flow and mass transport is of great interest in many fields including geotechnical, petroleum or civil engineering. In radioactive waste disposal there is considerable interest in crack behaviour in concrete structures for the following reasons: (i) open cracks are more permeable than the concrete matrix and may lead to increasing and unwanted water fluxes into the disposal facility, (ii) when water-filled there is little or no sorption in cracks and hence they could present preferential pathways for contaminant migration from the disposal facility to the environment and (iii) long-term chemical concrete degradation owing to e.g. carbonation could progress faster in the presence of cracks. Assessment of long-term behaviour of concretes and the wastes for which they provide containment, is feasible only by numerical modelling. This is even more true when cracks are considered and evaluated in the concrete degradation and mass transfer models. However, before the model is deemed suitable for assessments of real engineered structures, it should be thoroughly verified and if possible validated.